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Armstrong PM, Anderson JF, Sharma R, Misencik MJ, Bransfield A, Vossbrinck CR, Brackney DE. Field Isolation and Laboratory Vector-Host Studies of Brazoran Virus (Peribunyaviridae: Orthobunyavirus) from Florida. Am J Trop Med Hyg 2024; 110:968-970. [PMID: 38531101 PMCID: PMC11066360 DOI: 10.4269/ajtmh.23-0799] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2023] [Accepted: 12/27/2023] [Indexed: 03/28/2024] Open
Abstract
Brazoran virus was first isolated from Culex mosquitoes in Texas in 2012, yet little is known about this virus. We report the isolation of this virus from Culex erraticus from southern Florida during 2016. The Florida strain had a nucleotide identity of 96.3% (S segment), 99.1% (M segment), and 95.8% (L segment) to the Texas isolate. Culex quinquefasciatus and Aedes aegypti colonies were subsequently fed virus blood meals to determine their vector competence for Brazoran virus. Culex quinquefasciatus was susceptible to midgut infection, but few mosquitoes developed disseminated infections. Aedes aegypti supported disseminated infection, but virus transmission could not be demonstrated. Suckling mice became infected by intradermal inoculation without visible disease signs. The virus was detected in multiple mouse tissues but rarely infected the brain. This study documents the first isolation of Brazoran virus outside of Texas. Although this virus infected Ae. aegypti and Cx. quinquefasciatus in laboratory trials, their vector competence could not be demonstrated, suggesting they are unlikely vectors of Brazoran virus.
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Affiliation(s)
- Philip M. Armstrong
- Department of Entomology, The Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - John F. Anderson
- Department of Entomology, The Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Rohit Sharma
- Department of Entomology, The Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Michael J. Misencik
- Department of Entomology, The Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Angela Bransfield
- Department of Entomology, The Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Charles R. Vossbrinck
- Department of Environmental Science and Forestry, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Doug E. Brackney
- Department of Entomology, The Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
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Anderson JF, Molaei G, Fish D, Armstrong PM, Khalil N, Brudner S, Misencik MJ, Bransfield A, Olson M, Andreadis TG. Host-Feeding Behavior of Mosquitoes in the Florida Everglades. Vector Borne Zoonotic Dis 2024. [PMID: 38648543 DOI: 10.1089/vbz.2023.0072] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/25/2024] Open
Abstract
Background: West Nile virus (WNV), Everglades virus (EVEV), and five species of Orthobunyavirus were isolated from mosquitoes collected in the Everglades in 2016-2017. Prior studies of blood meals of mosquitoes in southern Florida have related findings to acquisition and transmission of EVEV, St. Louis encephalitis virus, and WNV, but not the Orthobunyavirus viruses associated with the subgenus Melanoconion of the genus Culex. Materials and Methods: In the present study, blood-fed mosquitoes were collected in the Everglades in 2016, 2017, 2021, and 2022, and from an industrial site in Naples, FL in 2017. Blood meals were identified to host species by PCR assays using mitochondrial cytochrome b gene. Results: Blood meals were identified from Anopheles crucians complex and 11 mosquito species captured in the Florida Everglades and from 3 species collected from an industrial site. The largest numbers of blood-fed specimens were from Culex nigripalpus, Culex erraticus, Culex cedecei, and Aedes taeniorhynchus. Cx. erraticus fed on mammals, birds, and reptiles, particularly American alligator. This mosquito species could transmit WNV to American alligator in the wild. Cx. nigripalpus acquired blood meals primarily from birds and mammals and frequently fed on medium-sized mammals and white-tailed deer. Water and wading birds were the primary avian hosts for Cx. nigripalpus and Cx. erraticus in the Everglades. Wading birds are susceptible to WNV and could serve as reservoir hosts. Cx. cedecei fed on five species of rodents, particularly black and hispid cotton rats. EVEV and three different species of Orthobunyavirus have been isolated from the hispid cotton rat and Cx. cedecei in the Everglades. Cx. cedecei is likely acquiring and transmitting these viruses among hispid cotton rats and other rodents. The marsh rabbit was a frequent host for An. crucians complex. An. crucians complex, and other species could acquire Tensaw virus from rabbits. Conclusions: Our study contributes to a better understanding of the host and viral associations of mosquito species in southwestern Florida.
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Affiliation(s)
- John F Anderson
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Goudarz Molaei
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, USA
| | - Durland Fish
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, USA
| | - Philip M Armstrong
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Noelle Khalil
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Samuel Brudner
- Quantitative Biology Institute, Department of Molecular, Cellular, Developmental Biology, Yale University, New Haven, Connecticut, USA
| | - Michael J Misencik
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Angela Bransfield
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Michael Olson
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Theodore G Andreadis
- Department of Entomology and Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
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Johnson RM, Stopard IJ, Byrne HM, Armstrong PM, Brackney DE, Lambert B. Investigating the dose-dependency of the midgut escape barrier using a mechanistic model of within-mosquito dengue virus population dynamics. PLoS Pathog 2024; 20:e1011975. [PMID: 38557892 PMCID: PMC11008821 DOI: 10.1371/journal.ppat.1011975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 04/11/2024] [Accepted: 01/16/2024] [Indexed: 04/04/2024] Open
Abstract
Arboviruses can emerge rapidly and cause explosive epidemics of severe disease. Some of the most epidemiologically important arboviruses, including dengue virus (DENV), Zika virus (ZIKV), Chikungunya (CHIKV) and yellow fever virus (YFV), are transmitted by Aedes mosquitoes, most notably Aedes aegypti and Aedes albopictus. After a mosquito blood feeds on an infected host, virus enters the midgut and infects the midgut epithelium. The virus must then overcome a series of barriers before reaching the mosquito saliva and being transmitted to a new host. The virus must escape from the midgut (known as the midgut escape barrier; MEB), which is thought to be mediated by transient changes in the permeability of the midgut-surrounding basal lamina layer (BL) following blood feeding. Here, we present a mathematical model of the within-mosquito population dynamics of DENV (as a model system for mosquito-borne viruses more generally) that includes the interaction of the midgut and BL which can account for the MEB. Our results indicate a dose-dependency of midgut establishment of infection as well as rate of escape from the midgut: collectively, these suggest that the extrinsic incubation period (EIP)-the time taken for DENV virus to be transmissible after infection-is shortened when mosquitoes imbibe more virus. Additionally, our experimental data indicate that multiple blood feeding events, which more closely mimic mosquito-feeding behavior in the wild, can hasten the course of infections, and our model predicts that this effect is sensitive to the amount of virus imbibed. Our model indicates that mutations to the virus which impact its replication rate in the midgut could lead to even shorter EIPs when double-feeding occurs. Mechanistic models of within-vector viral infection dynamics provide a quantitative understanding of infection dynamics and could be used to evaluate novel interventions that target the mosquito stages of the infection.
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Affiliation(s)
- Rebecca M. Johnson
- Center for Vector-Borne and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Isaac J. Stopard
- MRC Centre for Global Infectious Disease Analysis, School of Public Health, Faculty of Medicine, Imperial College London, London, United Kingdom
| | - Helen M. Byrne
- Mathematical Institute, University of Oxford, Oxford, United Kingdom
| | - Philip M. Armstrong
- Center for Vector-Borne and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Douglas E. Brackney
- Center for Vector-Borne and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Ben Lambert
- Department of Statistics, University of Oxford, Oxford, United Kingdom
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Shepard JJ, Armstrong PM. Jamestown Canyon virus comes into view: understanding the threat from an underrecognized arbovirus. J Med Entomol 2023; 60:1242-1251. [PMID: 37862091 DOI: 10.1093/jme/tjad069] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 05/08/2023] [Accepted: 06/08/2023] [Indexed: 10/21/2023]
Abstract
This review examines the epidemiology, ecology, and evolution of Jamestown Canyon virus (JCV) and highlights new findings from the literature to better understand the virus, the vectors driving its transmission, and its emergence as an agent of arboviral disease. We also reanalyze data from the Connecticut Arbovirus Surveillance Program which represents the largest dataset on JCV infection in mosquitoes. JCV is a member of the California serogroup of the genus Orthobunyavirus, family Peribunyaviridae, and is found throughout much of temperate North America. This segmented, negative-sense RNA virus evolves predominately by genetic drift punctuated by infrequent episodes of genetic reassortment among novel strains. It frequently infects humans within affected communities and occasionally causes febrile illness and neuroinvasive disease in people. Reported human cases are relatively rare but are on the rise during the last 20 yr, particularly within the northcentral and northeastern United States. JCV appears to overwinter and reemerge each season by transovarial or vertical transmission involving univoltine Aedes (Diptera: Culicidae) species, specifically members of the Aedes communis (de Geer) and Ae. stimulans (Walker) Groups. The virus is further amplified in a mosquito-deer transmission cycle involving a diversity of mammalophilic mosquito species. Despite progress in our understanding of this virus, many aspects of the vector biology, virology, and human disease remain poorly understood. Remaining questions and future directions of research are discussed.
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Affiliation(s)
- John J Shepard
- Center for Vector Biology and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
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5
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Johnson RM, Cozens DW, Ferdous Z, Armstrong PM, Brackney DE. Increased blood meal size and feeding frequency compromise Aedes aegypti midgut integrity and enhance dengue virus dissemination. PLoS Negl Trop Dis 2023; 17:e0011703. [PMID: 37910475 PMCID: PMC10619875 DOI: 10.1371/journal.pntd.0011703] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2023] [Accepted: 10/05/2023] [Indexed: 11/03/2023] Open
Abstract
Aedes aegypti is a highly efficient vector for numerous pathogenic arboviruses including dengue virus (DENV), Zika virus, and yellow fever virus. This efficiency can in part be attributed to their frequent feeding behavior. We previously found that acquisition of a second, full, non-infectious blood meal could accelerate virus dissemination within the mosquito by temporarily compromising midgut basal lamina integrity; however, in the wild, mosquitoes are often interrupted during feeding and only acquire partial or minimal blood meals. To explore the impact of this feeding behavior further, we examined the effects of partial blood feeding on DENV dissemination rates and midgut basal lamina damage in Ae. aegypti. DENV-infected mosquitoes given a secondary partial blood meal had intermediate rates of dissemination and midgut basal lamina damage compared to single-fed and fully double-fed counterparts. Subsequently, we evaluated if basal lamina damage accumulated across feeding episodes. Interestingly, within 24 hours of feeding, damage was proportional to the number of blood meals imbibed; however, this additive effect returned to baseline levels by 96 hours. These data reveal that midgut basal lamina damage and rates of dissemination are proportional to feeding frequency and size, and further demonstrate the impact that mosquito feeding behavior has on vector competence and arbovirus epidemiology. This work has strong implications for our understanding of virus transmission in the field and will be useful when designing laboratory experiments and creating more accurate models of virus spread and maintenance.
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Affiliation(s)
- Rebecca M. Johnson
- Connecticut Agricultural Experiment Station, Department of Entomology, Center for Vector Biology and Zoonotic Diseases, New Haven, Connecticut, United States of America
| | - Duncan W. Cozens
- Connecticut Agricultural Experiment Station, Department of Entomology, Center for Vector Biology and Zoonotic Diseases, New Haven, Connecticut, United States of America
| | - Zannatul Ferdous
- Connecticut Agricultural Experiment Station, Department of Entomology, Center for Vector Biology and Zoonotic Diseases, New Haven, Connecticut, United States of America
| | - Philip M. Armstrong
- Connecticut Agricultural Experiment Station, Department of Entomology, Center for Vector Biology and Zoonotic Diseases, New Haven, Connecticut, United States of America
| | - Doug E. Brackney
- Connecticut Agricultural Experiment Station, Department of Entomology, Center for Vector Biology and Zoonotic Diseases, New Haven, Connecticut, United States of America
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Johnson RM, Stopard IJ, Byrne HM, Armstrong PM, Brackney DE, Lambert B. Investigating the dose-dependency of the midgut escape barrier using a mechanistic model of within-mosquito dengue virus population dynamics. bioRxiv 2023:2023.09.28.559904. [PMID: 37808804 PMCID: PMC10557669 DOI: 10.1101/2023.09.28.559904] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/10/2023]
Abstract
Flaviviruses are arthropod-borne (arbo)viruses which can emerge rapidly and cause explosive epidemics of severe disease. Some of the most epidemiologically important flaviviruses, including dengue virus (DENV), Zika virus (ZIKV) and yellow fever virus (YFV), are transmitted by Aedes mosquitoes, most notably Aedes aegypti and Aedes albopictus. After a mosquito blood feeds on an infected host, virus enters the midgut and infects the midgut epithelium. The virus must then overcome a series of barriers before reaching the mosquito saliva and being transmitted to a new host. The virus must escape from the midgut (known as the midgut escape barrier; MEB), which is thought to be mediated by transient changes in the permeability of the midgut-surrounding basal lamina layer (BL) following blood feeding. Here, we present a mathematical model of the within-mosquito population dynamics of flaviviruses that includes the interaction of the midgut and BL which can account for the MEB. Our results indicate a dose-dependency of midgut establishment of infection as well as rate of escape from the midgut: collectively, these suggest that the extrinsic incubation period (EIP) - the time taken for DENV virus to be transmissible after infection - is shortened when mosquitoes imbibe more virus. Additionally, our experimental data indicates that multiple blood feeding events, which more closely mimic mosquito-feeding behavior in the wild, can hasten the course of infections, and our model predicts that this effect is sensitive to the amount of virus imbibed. Our model indicates that mutations to the virus which impact its replication rate in the midgut could lead to even shorter EIPs when double-feeding occurs. Mechanistic models of within-vector viral infection dynamics provide a quantitative understanding of infection dynamics and could be used to evaluate novel interventions that target the mosquito stages of the infection. Author summary Aedes mosquitoes are the main vectors of dengue virus (DENV), Zika virus (ZIKV) and yellow fever virus (YFV), all of which can cause severe disease in humans with dengue alone infecting an estimated 100-400 million people each year. Understanding the processes that affect whether, and at which rate, mosquitoes may transmit such viruses is, hence, paramount. Here, we present a mathematical model of virus dynamics within infected mosquitoes. By combining the model with novel experimental data, we show that the course of infection is sensitive to the initial dose of virus ingested by the mosquito. The data also indicates that mosquitoes which blood feed subsequent to becoming infected may be able to transmit infection earlier, which is reproduced in the model. This is important as many mosquito species feed multiple times during their lifespan and, any reduction in time to dissemination will increase the number of days that a mosquito is infectious and so enhance the risk of transmission. Our study highlights the key and complementary roles played by mathematical models and experimental data for understanding within-mosquito virus dynamics.
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Anderson JF, Main AJ, Armstrong PM, Andreadis TG. Seasonality of Mosquitoes in North Dakota, 2003-2006, with Four New State Records. J Am Mosq Control Assoc 2023; 39:68-74. [PMID: 37364183 DOI: 10.2987/23-7118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/28/2023]
Abstract
Thirty-seven species and subspecies of mosquitoes were identified from 3,580,610 specimens collected in eastern (Cass, Nelson, and Richland counties) and western (Williams County) North Dakota in 2003-2006. Four species were new state records (Aedes schizopinax, Psorophora ciliata, Ps. ferox, and Ps. horrida). Aedes vexans was dominant (82.9%). Other relatively abundant species were Ae. trivittatus (7.7%), Ae. melanimon (2.7%), Culex tarsalis (2.6%), Ae. dorsalis (1.6%), Ae. sticticus (1.0), and Culiseta inornata (0.9%). The seasonality of the species is presented.
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Hill V, Koch RT, Bialosuknia SM, Ngo K, Zink SD, Koetzner CA, Maffei JG, Dupuis AP, Backenson PB, Oliver J, Bransfield AB, Misencik MJ, Petruff TA, Shepard JJ, Warren JL, Gill MS, Baele G, Vogels CBF, Gallagher G, Burns P, Hentoff A, Smole S, Brown C, Osborne M, Kramer LD, Armstrong PM, Ciota AT, Grubaugh ND. Dynamics of eastern equine encephalitis virus during the 2019 outbreak in the Northeast United States. Curr Biol 2023:S0960-9822(23)00679-6. [PMID: 37295427 DOI: 10.1016/j.cub.2023.05.047] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 05/04/2023] [Accepted: 05/19/2023] [Indexed: 06/12/2023]
Abstract
Eastern equine encephalitis virus (EEEV) causes a rare but severe disease in horses and humans and is maintained in an enzootic transmission cycle between songbirds and Culiseta melanura mosquitoes. In 2019, the largest EEEV outbreak in the United States for more than 50 years occurred, centered in the Northeast. To explore the dynamics of the outbreak, we sequenced 80 isolates of EEEV and combined them with existing genomic data. We found that, similar to previous years, cases were driven by multiple independent but short-lived virus introductions into the Northeast from Florida. Once in the Northeast, we found that Massachusetts was important for regional spread. We found no evidence of any changes in viral, human, or bird factors which would explain the increase in cases in 2019, although the ecology of EEEV is complex and further data is required to explore these in more detail. By using detailed mosquito surveillance data collected by Massachusetts and Connecticut, however, we found that the abundance of Cs. melanura was exceptionally high in 2019, as was the EEEV infection rate. We employed these mosquito data to build a negative binomial regression model and applied it to estimate early season risks of human or horse cases. We found that the month of first detection of EEEV in mosquito surveillance data and vector index (abundance multiplied by infection rate) were predictive of cases later in the season. We therefore highlight the importance of mosquito surveillance programs as an integral part of public health and disease control.
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Affiliation(s)
- Verity Hill
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA.
| | - Robert T Koch
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Sean M Bialosuknia
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA
| | - Kiet Ngo
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA
| | - Steven D Zink
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA
| | - Cheri A Koetzner
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA
| | - Joseph G Maffei
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA
| | - Alan P Dupuis
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA
| | - P Bryon Backenson
- New York State Department of Health, Bureau of Communicable Disease Control, Albany, NY 12237, USA
| | - JoAnne Oliver
- New York State Department of Health, Bureau of Communicable Disease Control, Syracuse, NY 13202, USA; Division of Environmental and Renewable Resources, State University of New York at Morrisville - School of Agriculture, Business and Technology, Morrisville, NY 13408, USA
| | - Angela B Bransfield
- Center for Vector Biology and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Michael J Misencik
- Center for Vector Biology and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Tanya A Petruff
- Center for Vector Biology and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - John J Shepard
- Center for Vector Biology and Zoonotic Diseases, Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT 06511, USA
| | - Joshua L Warren
- Department of Biostatistics, Yale School of Public Health, New Haven, CT 06510, USA; Public Health Modeling Unit, Yale School of Public Health, New Haven, CT 06510, USA
| | - Mandev S Gill
- Department of Statistics, University of Georgia, Athens, GA 30602, USA
| | - Guy Baele
- Department of Microbiology, Immunology and Transplantation, Rega Institute, KU Leuven, Leuven BE-3000, Belgium
| | - Chantal B F Vogels
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA
| | - Glen Gallagher
- Massachusetts Department of Public Health, Boston, MA 02108, USA; Rhode Island State Health Laboratory, Rhode Island Department of Health, Providence, RI 02904, USA
| | - Paul Burns
- Massachusetts Department of Public Health, Boston, MA 02108, USA
| | - Aaron Hentoff
- Massachusetts Department of Public Health, Boston, MA 02108, USA
| | - Sandra Smole
- Massachusetts Department of Public Health, Boston, MA 02108, USA
| | - Catherine Brown
- Massachusetts Department of Public Health, Boston, MA 02108, USA
| | - Matthew Osborne
- Massachusetts Department of Public Health, Boston, MA 02108, USA
| | - Laura D Kramer
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA; Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, NY 12237, USA
| | - Philip M Armstrong
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA; Division of Environmental and Renewable Resources, State University of New York at Morrisville - School of Agriculture, Business and Technology, Morrisville, NY 13408, USA.
| | - Alexander T Ciota
- The Arbovirus Laboratory, New York State Department of Health, Wadsworth Center, Slingerlands, NY 12159, USA; Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, NY 12237, USA.
| | - Nathan D Grubaugh
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, CT 06510, USA; Department of Biostatistics, Yale School of Public Health, New Haven, CT 06510, USA; Department of Ecology and Evolutionary Biology, Yale University, New Haven, CT, USA.
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McMillan JR, Chaves LF, Armstrong PM. Ecological predictors of mosquito population and arbovirus transmission synchrony estimates. J Med Entomol 2023; 60:564-574. [PMID: 36964697 PMCID: PMC10179454 DOI: 10.1093/jme/tjad024] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2022] [Revised: 02/07/2023] [Accepted: 02/24/2023] [Indexed: 05/13/2023]
Abstract
Quantifying synchrony in species population fluctuations and determining its driving factors can inform multiple aspects of ecological and epidemiological research and policy decisions. We examined seasonal mosquito and arbovirus surveillance data collected in Connecticut, United States from 2001 to 2020 to quantify spatial relationships in 19 mosquito species and 7 arboviruses timeseries accounting for environmental factors such as climate and land cover characteristics. We determined that mosquito collections, on average, were significantly correlated up to 10 km though highly variable among the examined species. Few arboviruses displayed any synchrony and significant maximum correlated distances never exceeded 5 km. After accounting for distance, mixed effects models showed that mosquito or arbovirus identity explained more variance in synchrony estimates than climate or land cover factors. Correlated mosquito collections up to 10-20 km suggest that mosquito control operations for nuisance and disease vectors alike must expand treatment zones to regional scales for operations to have population-level impacts. Species identity matters as well, and some mosquito species will require much larger treatment zones than others. The much shorter correlated detection distances for arboviruses reinforce the notion that focal-level processes drive vector-borne pathogen transmission dynamics and risk of spillover into human populations.
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Affiliation(s)
- Joseph R McMillan
- Department of Biological Sciences, Texas Tech University, Lubbock, TX, USA
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | - Luis Fernando Chaves
- Department of Environmental and Occupational Health, School of Public Health, Indiana University, Bloomington, IN, USA
| | - Philip M Armstrong
- Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
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10
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Hill V, Koch RT, Bialosuknia SM, Ngo K, Zink SD, Koetzner CA, Maffei JG, Dupuis AP, Backenson PB, Oliver J, Bransfield AB, Misencik MJ, Petruff TA, Shepard JJ, Warren JL, Gill MS, Baele G, Vogels CBF, Gallagher G, Burns P, Hentoff A, Smole S, Brown C, Osborne M, Kramer LD, Armstrong PM, Ciota AT, Grubaugh ND. Dynamics of Eastern equine encephalitis virus during the 2019 outbreak in the Northeast United States. medRxiv 2023:2023.03.06.23286851. [PMID: 36945576 PMCID: PMC10029029 DOI: 10.1101/2023.03.06.23286851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/23/2023]
Abstract
Eastern equine encephalitis virus (EEEV) causes a rare but severe disease in horses and humans, and is maintained in an enzootic transmission cycle between songbirds and Culiseta melanura mosquitoes. In 2019, the largest EEEV outbreak in the United States for more than 50 years occurred, centered in the Northeast. To explore the dynamics of the outbreak, we sequenced 80 isolates of EEEV and combined them with existing genomic data. We found that, like previous years, cases were driven by frequent short-lived virus introductions into the Northeast from Florida. Once in the Northeast, we found that Massachusetts was important for regional spread. We found no evidence of any changes in viral, human, or bird factors which would explain the increase in cases in 2019. By using detailed mosquito surveillance data collected by Massachusetts and Connecticut, however, we found that the abundance of Cs. melanura was exceptionally high in 2019, as was the EEEV infection rate. We employed these mosquito data to build a negative binomial regression model and applied it to estimate early season risks of human or horse cases. We found that the month of first detection of EEEV in mosquito surveillance data and vector index (abundance multiplied by infection rate) were predictive of cases later in the season. We therefore highlight the importance of mosquito surveillance programs as an integral part of public health and disease control.
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11
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Bransfield AB, Misencik MJ, Brackney DE, Armstrong PM. Limited Capacity for Aedes aegypti to Mechanically Transmit Chikungunya Virus and Dengue Virus. Am J Trop Med Hyg 2022; 107:1239-1241. [PMID: 36315998 PMCID: PMC9768263 DOI: 10.4269/ajtmh.22-0323] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2022] [Accepted: 09/12/2022] [Indexed: 11/05/2022] Open
Abstract
Mechanical transmission is an understudied mode of arbovirus transmission that occurs when a biting insect transmits virus among hosts by the direct transfer of virus particles contaminating its mouthparts. Multiple arboviruses have been shown to be capable of utilizing this transmission route, but most studies were conducted 40 to 70 years ago using dated methodologies. To gain a better understanding of this phenomenon, we used molecular techniques to evaluate the efficiency of mechanical transmission by Aedes aegypti mosquitoes for two evolutionarily divergent arboviruses, chikungunya virus (CHIKV) and dengue virus (DENV). Viral RNA and/or infectious DENV could be detected on 13.8% of mosquito proboscises sampled immediately after an infectious bloodmeal, but positivity rates declined within hours. CHIKV RNA and/or infectious virus was detected on 38.8% of proboscises immediately after feeding but positivity rates dropped to 2.5% within 4 hours. RNA copy numbers were low for both viruses, and we were unable to demonstrate mechanical transmission of CHIKV using an established animal model, suggesting that this mode of transmission is unlikely under natural conditions.
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Affiliation(s)
- Angela B. Bransfield
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Michael J. Misencik
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Doug E. Brackney
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, Connecticut
| | - Philip M. Armstrong
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, Connecticut
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12
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Gloria-Soria A, Shragai T, Ciota AT, Duval TB, Alto BW, Martins AJ, Westby KM, Medley KA, Unlu I, Campbell SR, Kawalkowski M, Tsuda Y, Higa Y, Indelicato N, Leisnham PT, Caccone A, Armstrong PM. Population genetics of an invasive mosquito vector, Aedes albopictus in the Northeastern USA. NB 2022. [DOI: 10.3897/neobiota.78.84986] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
Abstract
The Asian tiger mosquito (Aedes albopictus) arrived in the USA in the 1980’s and rapidly spread throughout eastern USA within a decade. The predicted northern edge of its overwintering distribution on the East Coast of the USA roughly falls across New York, Connecticut, and Massachusetts, where the species has been recorded as early as 2000. It is unclear whether Ae. albopictus populations have become established and survive the cold winters in these areas or are recolonized every year. We genotyped and analyzed populations of Ae. albopictus from the northeast USA using 15 microsatellite markers and compared them with other populations across the country and to representatives of the major global genetic clades to investigate their connectivity and stability. Founder effects or bottlenecks were rare at the northern range of the Ae. albopictus distribution in the northeastern USA, with populations displaying high levels of genetic diversity and connectivity along the East Coast. There is no evidence of population turnover in Connecticut during the course of three consecutive years, with consistent genetic structure throughout this period. Overall, these results support the presence of established populations of Ae. albopictus in New York, Connecticut, and Massachusetts, successfully overwintering and migrating in large numbers. Given the stability and interconnectedness of these populations, Ae. albopictus has the potential to continue to proliferate and expand its range northward under mean warming conditions of climate change. Efforts to control Ae. albopictus in these areas should thus focus on vector suppression rather than eradication strategies, as local populations have become firmly established and are expected to reemerge every summer.
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13
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McMillan JR, Olson MM, Petruff T, Shepard JJ, Armstrong PM. Impacts of Lysinibacillus sphaericus on mosquito larval community composition and larval competition between Culex pipiens and Aedes albopictus. Sci Rep 2022; 12:18013. [PMID: 36289303 PMCID: PMC9606275 DOI: 10.1038/s41598-022-21939-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Accepted: 10/06/2022] [Indexed: 01/24/2023] Open
Abstract
Effectiveness of mosquito larvicide active ingredients (AI), such as Lysinibacillus sphaericus, varies between species, yet little is known regarding how differential effectiveness manifests in larval communities in applied settings. To examine how differential effectiveness of L. sphaericus influences larval community dynamics, we performed two experiments. We performed a field experiment in which containers were seeded with a standardized nutrient treatment, mosquitoes colonized the containers, and then containers received one of three L. sphaericus applications. We then performed competition assays between Culex pipiens and Aedes albopictus in low nutrient environments using multiple interspecific ratios and the presence/absence of a low dose of L. sphaericus. Field results demonstrated elimination of Culex spp. from treated containers while container breeding Aedes spp. proliferated across all treatments. Lysinibacillus sphaericus did not influence competition between Cx. pipiens and Ae. albopictus, and the L. sphaericus application eliminated Cx. pipiens in all treatment replicates while survival of Ae. albopictus was similar between treated and untreated containers across interspecific ratios. Lysinibacillus sphaericus is an effective AI for control of Culex spp. However, different AIs should be utilized in habitats containing non-Culex genera while a mix of AIs should be utilized where coexistence of multiple genera is expected or confirmed.
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Affiliation(s)
- Joseph R. McMillan
- grid.264784.b0000 0001 2186 7496Department of Biological Sciences, Texas Tech University, 2901 Main St., Rm 212, Lubbock, TX 79409 USA ,grid.421470.40000 0000 8788 3977Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT USA
| | - Michael M. Olson
- grid.421470.40000 0000 8788 3977Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT USA
| | - Tanya Petruff
- grid.421470.40000 0000 8788 3977Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT USA
| | - John J. Shepard
- grid.421470.40000 0000 8788 3977Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT USA
| | - Philip M. Armstrong
- grid.421470.40000 0000 8788 3977Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, CT USA
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14
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Anderson JF, Fish D, Armstrong PM, Misencik MJ, Bransfield A, Ferrandino FJ, Andreadis TG, Stenglein MD, Kapuscinski ML. Seasonal Dynamics of Mosquito-Borne Viruses in the Southwestern Florida Everglades, 2016, 2017. Am J Trop Med Hyg 2022; 106:610-622. [PMID: 35008051 PMCID: PMC8832897 DOI: 10.4269/ajtmh.20-1547] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Accepted: 11/03/2021] [Indexed: 02/03/2023] Open
Abstract
Mosquitoes were collected for 12 consecutive months beginning June 2016, from 11 locations in the Florida Everglades, Collier County, and tested for viruses by isolation in Vero cells and subsequent identification. One species complex and 31 species of mosquitoes were identified from 668,809 specimens. Ochlerotatus taeniorhynchus comprised 72.2% of the collection. Other notable species were Anopheles crucians complex, Culex nigripalpus, Cx. erraticus, and Cx. cedecei. Seven species of virus were identified from 110 isolations: Everglades, Gumbo Limbo, Mahogany Hammock, Pahayokee, Shark River, Tensaw, and West Nile viruses. Everglades, West Nile, Tensaw, and Mahogany Hammock viruses were most frequently isolated. Largest numbers of viruses were identified from Cx. cedecei, Cx. nigripalpus, and An. crucians complex. Five species of virus were isolated from Cx. cedecei. Viruses were isolated from mangrove, cypress swamp, hardwood hammock, and sawgrass habitats. West Nile virus was isolated August through October when Cx. nigripalpus was most abundant. Everglades virus was the most frequently isolated virus from nine species of mosquitoes collected from June through August. Tensaw virus was isolated primarily from Anopheles species. Isolations were made in July, August, January, February, and April, suggesting that this virus may be present in host-seeking mosquitoes throughout the year. Mahogany Hammock, Shark River, Gumbo Limbo, and Pahayokee viruses were isolated primarily from Cx. cedecei from June through December. Shotgun metagenomic sequencing was used to document that seven pools of Cx. cedecei were infected with two arboviruses. As communities expand into the Everglades, more humans will become exposed to arboviruses.
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Affiliation(s)
- John F. Anderson
- Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut;,Address correspondence to John F. Anderson, The Connecticut Agricultural Experiment Station, 123 Huntington St., New Haven, CT 06511-1106. E-mail:
| | - Durland Fish
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut
| | - Philip M. Armstrong
- Department of Environmental Sciences and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Michael J. Misencik
- Department of Environmental Sciences and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Angela Bransfield
- Department of Environmental Sciences and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Francis J. Ferrandino
- Department of Plant Pathology, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Theodore G. Andreadis
- Department of Environmental Sciences and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Mark D. Stenglein
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
| | - Marylee L. Kapuscinski
- Center for Vector-Borne Infectious Diseases, Department of Microbiology, Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Colorado State University, Fort Collins, Colorado
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15
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Armstrong PM, Andreadis TG. Ecology and Epidemiology of Eastern Equine Encephalitis Virus in the Northeastern United States: An Historical Perspective. J Med Entomol 2022; 59:1-13. [PMID: 34734628 PMCID: PMC8755988 DOI: 10.1093/jme/tjab077] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2021] [Indexed: 05/10/2023]
Abstract
In the current review, we examine the regional history, ecology, and epidemiology of eastern equine encephalitis virus (EEEV) to investigate the major drivers of disease outbreaks in the northeastern United States. EEEV was first recognized as a public health threat during an outbreak in eastern Massachusetts in 1938, but historical evidence for equine epizootics date back to the 1800s. Since then, sporadic disease outbreaks have reoccurred in the Northeast with increasing frequency and northward expansion of human cases during the last 20 yr. Culiseta melanura (Coquillett) (Diptera: Culicidae) serves as the main enzootic vector that drives EEEV transmission among wild birds, but this mosquito species will occasionally feed on mammals. Several species have been implicated as bridge vectors to horses and humans, with Coquilletstidia perturbans (Walker) as a leading suspect based on its opportunistic feeding behavior, vector competence, and high infection rates during recent disease outbreaks. A diversity of bird species are reservoir competent, exposed to EEEV, and serve as hosts for Cs. melanura, with a few species, including the wood thrush (Hlocichia mustelina) and the American robin (Turdus migratorius), contributing disproportionately to virus transmission based on available evidence. The major factors responsible for the sustained resurgence of EEEV are considered and may be linked to regional landscape and climate changes that support higher mosquito densities and more intense virus transmission.
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Affiliation(s)
- Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, P.O. Box 1106. 123 Huntington Street, New Haven, CT 06504, USA
| | - Theodore G Andreadis
- Center for Vector Biology and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, P.O. Box 1106. 123 Huntington Street, New Haven, CT 06504, USA
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16
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McMillan JR, Harden CA, Burtis JC, Breban MI, Shepard JJ, Petruff TA, Misencik MJ, Bransfield AB, Poggi JD, Harrington LC, Andreadis TG, Armstrong PM. The community-wide effectiveness of municipal larval control programs for West Nile virus risk reduction in Connecticut, USA. Pest Manag Sci 2021; 77:5186-5201. [PMID: 34272800 PMCID: PMC9291174 DOI: 10.1002/ps.6559] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/15/2021] [Revised: 07/02/2021] [Accepted: 07/16/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Mosquito larval control through the use of insecticides is the most common strategy for suppressing West Nile virus (WNV) vector populations in Connecticut (CT), USA. To evaluate the ability of larval control to reduce entomological risk metrics associated with WNV, we performed WNV surveillance and assessments of municipal larvicide application programs in Milford and Stratford, CT in 2019 and 2020. Each town treated catch basins and nonbasin habitats (Milford only) with biopesticide products during both WNV transmission seasons. Adult mosquitoes were collected weekly with gravid and CO2 -baited light traps and tested for WNV; larvae and pupae were sampled weekly from basins within 500 m of trapping sites, and Culex pipiens larval mortality was determined with laboratory bioassays of catch basin water samples. RESULTS Declines in 4th instar larvae and pupae were observed in catch basins up to 2-week post-treatment, and we detected a positive relationship between adult female C. pipiens collections in gravid traps and pupal abundance in basins. We also detected a significant difference in total light trap collections between the two towns. Despite these findings, C. pipiens adult collections and WNV mosquito infection prevalence in gravid traps were similar between towns. CONCLUSION Larvicide applications reduced pupal abundance and the prevalence of host-seeking adults with no detectable impact on entomological risk metrics for WNV. Further research is needed to better determine the level of mosquito larval control required to reduce WNV transmission risk.
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Affiliation(s)
- Joseph R McMillan
- The Connecticut Agricultural Experiment StationNew HavenCTUSA
- The Northeast Regional Center of Excellence in Vector‐borne DiseasesCornell UniversityIthacaNew YorkUSA
| | | | - James C Burtis
- The Northeast Regional Center of Excellence in Vector‐borne DiseasesCornell UniversityIthacaNew YorkUSA
- Division of Vector‐borne DiseasesCenters for Disease Control and PreventionFort CollinsCOUSA
| | | | - John J Shepard
- The Connecticut Agricultural Experiment StationNew HavenCTUSA
| | - Tanya A Petruff
- The Connecticut Agricultural Experiment StationNew HavenCTUSA
| | | | | | - Joseph D Poggi
- The Northeast Regional Center of Excellence in Vector‐borne DiseasesCornell UniversityIthacaNew YorkUSA
- Cornell UniversityIthacaNYUSA
| | - Laura C Harrington
- The Northeast Regional Center of Excellence in Vector‐borne DiseasesCornell UniversityIthacaNew YorkUSA
- Cornell UniversityIthacaNYUSA
| | - Theodore G Andreadis
- The Connecticut Agricultural Experiment StationNew HavenCTUSA
- The Northeast Regional Center of Excellence in Vector‐borne DiseasesCornell UniversityIthacaNew YorkUSA
| | - Philip M Armstrong
- The Connecticut Agricultural Experiment StationNew HavenCTUSA
- The Northeast Regional Center of Excellence in Vector‐borne DiseasesCornell UniversityIthacaNew YorkUSA
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17
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Khalil N, Little EAH, Akaratovic KI, Kiser JP, Abadam CF, Yuan KJ, Misencik MJ, Armstrong PM, Molaei G. Host Associations of Culex pipiens: A Two-Year Analysis of Bloodmeal Sources and Implications for Arboviral Transmission in Southeastern Virginia. Vector Borne Zoonotic Dis 2021; 21:961-972. [PMID: 34665047 DOI: 10.1089/vbz.2021.0069] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Understanding vector-host interactions is crucial for evaluating the role of mosquito species in enzootic cycling and epidemic/epizootic transmission of arboviruses, as well as assessing vertebrate host contributions to maintenance and amplification in different virus foci. To investigate blood-feeding pattern of Culex pipiens, engorged mosquitoes were collected on a weekly basis at 50 sites throughout Suffolk, Virginia, using Centers for Disease Control and Prevention miniature light traps, BG-Sentinel traps, and modified Reiter gravid traps. Vertebrate hosts of mosquitoes were identified by amplifying and sequencing portions of the mitochondrial cytochrome b gene. Of 281 Cx. pipiens bloodmeals successfully identified to species, 255 (90.7%) contained solely avian blood, 13 (4.6%) mammalian, 1 (0.4%) reptilian, and 12 (4.3%) both avian and mammalian blood. Nineteen avian species were identified as hosts for Cx. pipiens with American robin (n = 141, 55.3% of avian hosts) and northern cardinal (n = 57, 22.4%) as the most common hosts. More American robin feedings took place in areas of higher development. Three mammalian species were also identified as hosts for Cx. pipiens with Virginia opossum and domestic cat as the most common hosts in this class (each n = 6, 46.2% of mammalian hosts). There was no significant seasonal difference in the proportion of bloodmeals obtained from avian hosts, but there was a decrease in the proportion of bloodmeals from mammalian hosts from spring to fall. One engorged specimen of Cx. pipiens with Virginia opossum-derived bloodmeal tested positive for West Nile virus (WNV), and another with black-and-white warbler-derived bloodmeal tested positive for eastern equine encephalitis virus. Our findings, in conjunction with the results of vector competence studies and virus isolation from field-collected mosquitoes, lend additional support that Cx. pipiens serves as the principal enzootic vector and potential epizootic/epidemic vector of WNV in southeastern Virginia.
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Affiliation(s)
- Noelle Khalil
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA.,Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Eliza A H Little
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA.,Department of Entomology, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Karen I Akaratovic
- Suffolk Mosquito Control, Department of Public Works, Suffolk, Virginia, USA
| | - Jay P Kiser
- Suffolk Mosquito Control, Department of Public Works, Suffolk, Virginia, USA
| | - Charles F Abadam
- Suffolk Mosquito Control, Department of Public Works, Suffolk, Virginia, USA
| | - Karen J Yuan
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, USA
| | - Michael J Misencik
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA.,Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA
| | - Philip M Armstrong
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA.,Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA.,Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, USA
| | - Goudarz Molaei
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA.,Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, USA.,Department of Epidemiology of Microbial Diseases, Yale School of Public Health, New Haven, Connecticut, USA
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18
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Sharma R, Cozens DW, Armstrong PM, Brackney DE. Vector competence of human-biting ticks Ixodes scapularis, Amblyomma americanum and Dermacentor variabilis for Powassan virus. Parasit Vectors 2021; 14:466. [PMID: 34503550 PMCID: PMC8427896 DOI: 10.1186/s13071-021-04974-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2021] [Accepted: 08/22/2021] [Indexed: 02/07/2023] Open
Abstract
Background Powassan virus (POWV; genus Flavivirus) is the sole North American member of the tick-borne encephalitis sero-complex and an increasing public health threat in the USA. Maintained in nature by Ixodes spp. ticks, POWV has also been isolated from species of other hard tick genera, yet it is unclear if these species can serve as vectors. Dermacentor variabilis and Amblyomma americanum share geographic and ecologic overlap with Ixodes spp. ticks and POWV transmission foci, raising the possibility that POWV could become established in these tick species and leading to range expansion and increased human risk. Therefore, we assessed the competency of Ixodes scapularis, D. variabilis and A. americanum for POWV lineage II (POWV II). Methods Larvae from all three species were co-infested on POWV-infected Balb/c mice. The engorged larvae were allowed to molt to nymphs and screened for the presence of POWV II RNA by reverse transcription-qPCR. Eight infected nymphs from each species were allowed to individually feed on a naïve mouse. Mice were screened for the presence of POWV II RNA to determine infection status. Results The results demonstrated that larvae from all three tick species were able to efficiently acquire POWV II via feeding on viremic mice, maintain infection through molting and successively transmit POWV to naïve mice at the nymphal stage at comparable rates across all three species. Conclusions Our findings reveal that non-Ixodes tick species can serve as competent vectors for POWV and highlight the potential role of these species in the ecology and epidemiology of POWV. Future studies examining the possible implications of these findings on POWV epidemiology and the adaptability of POWV in these new vectors are warranted. Graphical abstract ![]()
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Affiliation(s)
- Rohit Sharma
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA.,Deptartment of Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA
| | - Duncan W Cozens
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA.,Deptartment of Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA
| | - Philip M Armstrong
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA.,Deptartment of Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA
| | - Douglas E Brackney
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA. .,Deptartment of Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington St, New Haven, CT, 06511, USA.
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19
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Brown SC, Cormier J, Tuan J, Lier AJ, McGuone D, Armstrong PM, Kaddouh F, Parikh S, Landry ML, Gobeske KT. Four Human Cases of Eastern Equine Encephalitis in Connecticut, USA, during a Larger Regional Outbreak, 2019. Emerg Infect Dis 2021; 27. [PMID: 34289334 PMCID: PMC8314835 DOI: 10.3201/eid2708.203730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
Abstract
Incidence increased among human and equine hosts after primary and bridge mosquito virus vectors more than doubled over normal levels 1 month earlier in the season than usual. During 3 weeks in 2019, 4 human cases of Eastern equine encephalitis (EEE) were diagnosed at a single hospital in Connecticut, USA. The cases coincided with notable shifts in vector–host infection patterns in the northeastern United States and signified a striking change in EEE incidence. All 4 cases were geographically clustered, rapidly progressive, and neurologically devastating. Diagnostic tests conducted by a national commercial reference laboratory revealed initial granulocytic cerebrospinal fluid pleocytosis and false-negative antibody results. EEE virus infection was diagnosed only after patient samples were retested by the arbovirus laboratory of the Centers for Disease Control and Prevention in Fort Collins, Colorado, USA. The crucial diagnostic challenges, clinical findings, and epidemiologic patterns revealed in this outbreak can inform future public health and clinical practice.
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20
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Wilson SN, López K, Coutermash-Ott S, Auguste DI, Porier DL, Armstrong PM, Andreadis TG, Eastwood G, Auguste AJ. La Crosse Virus Shows Strain-Specific Differences in Pathogenesis. Pathogens 2021; 10:pathogens10040400. [PMID: 33805389 PMCID: PMC8066585 DOI: 10.3390/pathogens10040400] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/31/2021] [Revised: 03/19/2021] [Accepted: 03/24/2021] [Indexed: 01/08/2023] Open
Abstract
La Crosse virus (LACV) is the leading cause of pediatric viral encephalitis in North America, and is an important public health pathogen. Historically, studies involving LACV pathogenesis have focused on lineage I strains, but no former work has explored the pathogenesis between or within lineages. Given the absence of LACV disease in endemic regions where a robust entomological risk exists, we hypothesize that some LACV strains are attenuated and demonstrate reduced neuroinvasiveness. Herein, we compared four viral strains representing all three lineages to determine differences in neurovirulence or neuroinvasiveness using three murine models. A representative strain from lineage I was shown to be the most lethal, causing >50% mortality in each of the three mouse studies. However, other strains only presented excessive mortality (>50%) within the suckling mouse neurovirulence model. Neurovirulence was comparable among strains, but viruses differed in their neuroinvasive capacities. Our studies also showed that viruses within lineage III vary in pathogenesis with contemporaneous strains, showing reduced neuroinvasiveness compared to an ancestral strain from the same U.S. state (i.e., Connecticut). These findings demonstrate that LACV strains differ markedly in pathogenesis, and that strain selection is important for assessing vaccine and therapeutic efficacies.
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Affiliation(s)
- Sarah N. Wilson
- Department of Entomology, College of Agriculture and Life Sciences, Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA; (S.N.W.); (K.L.); (D.I.A.); (D.L.P.); (G.E.)
| | - Krisangel López
- Department of Entomology, College of Agriculture and Life Sciences, Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA; (S.N.W.); (K.L.); (D.I.A.); (D.L.P.); (G.E.)
| | - Sheryl Coutermash-Ott
- Department of Biomedical Sciences and Pathobiology, Virginia Tech, VA-MD College of Veterinary Medicine, Blacksburg, VA 24061, USA;
| | - Dawn I. Auguste
- Department of Entomology, College of Agriculture and Life Sciences, Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA; (S.N.W.); (K.L.); (D.I.A.); (D.L.P.); (G.E.)
| | - Danielle L. Porier
- Department of Entomology, College of Agriculture and Life Sciences, Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA; (S.N.W.); (K.L.); (D.I.A.); (D.L.P.); (G.E.)
| | - Philip M. Armstrong
- Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06504, USA; (P.M.A.); (T.G.A.)
| | - Theodore G. Andreadis
- Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06504, USA; (P.M.A.); (T.G.A.)
| | - Gillian Eastwood
- Department of Entomology, College of Agriculture and Life Sciences, Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA; (S.N.W.); (K.L.); (D.I.A.); (D.L.P.); (G.E.)
- Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
| | - Albert J. Auguste
- Department of Entomology, College of Agriculture and Life Sciences, Fralin Life Science Institute, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA; (S.N.W.); (K.L.); (D.I.A.); (D.L.P.); (G.E.)
- Center for Emerging, Zoonotic, and Arthropod-Borne Pathogens, Virginia Polytechnic Institute and State University, Blacksburg, VA 24061, USA
- Correspondence: ; Tel.: +1-540-231-6158
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21
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Burtis JC, Poggi JD, McMillan JR, Crans SC, Campbell SR, Isenberg A, Pulver J, Casey P, White K, Zondag C, Badger JR, Berger R, Betz J, Giordano S, Kawalkowski M, Petersen JL, Williams G, Andreadis TG, Armstrong PM, Harrington LC. NEVBD Pesticide Resistance Monitoring Network: Establishing a Centralized Network to Increase Regional Capacity for Pesticide Resistance Detection and Monitoring. J Med Entomol 2021; 58:787-797. [PMID: 33128057 DOI: 10.1093/jme/tjaa236] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2020] [Indexed: 06/11/2023]
Abstract
Pesticide resistance in arthropod vectors of disease agents is a growing issue globally. Despite the importance of resistance monitoring to inform mosquito control programs, no regional monitoring programs exist in the United States. The Northeastern Regional Center for Excellence in Vector-Borne Diseases (NEVBD) is a consortium of researchers and public health practitioners with a primary goal of supporting regional vector control activities. NEVBD initiated a pesticide resistance monitoring program to detect resistant mosquito populations throughout the northeastern United States. A regionwide survey was distributed to vector control agencies to determine needs and refine program development and in response, a specimen submission system was established, allowing agencies to submit Culex pipiens (L.) (Diptera:Culicidae) and Aedes albopictus (Skuse) (Diptera: Culicidae) for pesticide resistance testing. NEVBD also established larvicide resistance diagnostics for Bacillus thuringiensis israelensis (Bti) and methoprene. Additional diagnostics were developed for Cx. pipiens resistance to Lysinibacillus sphaericus. We received 58 survey responses, representing at least one agency from each of the 13 northeastern U.S. states. Results indicated that larvicides were deployed more frequently than adulticides, but rarely paired with resistance monitoring. Over 18,000 mosquitoes were tested from six states. Widespread low-level (1 × LC-99) methoprene resistance was detected in Cx. pipiens, but not in Ae. albopictus. No resistance to Bti or L. sphaericus was detected. Resistance to pyrethroids was detected in many locations for both species. Our results highlight the need for increased pesticide resistance testing in the United States and we provide guidance for building a centralized pesticide resistance testing program.
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Affiliation(s)
- James C Burtis
- Department of Entomology, Cornell University, Ithaca, NY
| | - Joseph D Poggi
- Department of Entomology, Cornell University, Ithaca, NY
| | | | - Scott C Crans
- NJDEP Office of Mosquito Control Coordination, Trenton, NJ
| | | | - Amy Isenberg
- Rockland County Department of Health, Pomona, NY
| | | | - Patti Casey
- Vermont Agency of Agriculture, Food & Markets, Montpelier, VT
| | | | - Craig Zondag
- Lemon Fair Insect Control District, Weybridge, VT
| | - John R Badger
- Delaware Division of Fish and Wildlife, Mosquito Control Section, Milford, DE
| | - Russell Berger
- Morris County Division of Mosquito Control, Morristown, NJ
| | - John Betz
- Department of Public Works, Cumberland County Mosquito Control, Bridgeton, NJ 08302
| | | | | | - John L Petersen
- Center for Vector Biology, Rutgers University, New Brunswick, NJ
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22
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Gloria-Soria A, Payne AF, Bialosuknia SM, Stout J, Mathias N, Eastwood G, Ciota AT, Kramer LD, Armstrong PM. Vector Competence of Aedes albopictus Populations from the Northeastern United States for Chikungunya, Dengue, and Zika Viruses. Am J Trop Med Hyg 2020; 104:1123-1130. [PMID: 33355070 PMCID: PMC7941830 DOI: 10.4269/ajtmh.20-0874] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2020] [Accepted: 11/10/2020] [Indexed: 11/07/2022] Open
Abstract
The Asian tiger mosquito (Aedes albopictus) is an important vector of a number of arboviruses, including Zika (ZIKV), dengue (DENV), and chikungunya (CHIKV) viruses, and has recently expanded its range in the eastern United States to southern New England and New York. Given the recent establishment and proliferation of Ae. albopictus in this region and the increasing amount of international travel between the United States and endemic countries, there is a need to elucidate the public health risk posed by this mosquito species in the Northeast. Accordingly, we evaluated the competence of four Ae. albopictus populations from Connecticut and New York, for two strains each of ZIKV, DENV serotype 2 (DENV-2), and CHIKV, currently circulating in the Americas, to evaluate the local transmission risk by this vector. We found that local Ae. albopictus populations are susceptible to infection by all three viruses but are most capable of transmitting CHIKV. Variation in competence was observed for ZIKV and CHIKV, driven by the virus strains and mosquito population, whereas competence was more homogeneous for the DENV-2 strains under evaluation. These results suggest that under optimal circumstances, Ae. albopictus could support localized transmission of these viruses and emphasize the importance of maintaining mosquito surveillance and control programs to suppress Ae. albopictus populations and limit further range expansion of this species.
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Affiliation(s)
- Andrea Gloria-Soria
- Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Anne F. Payne
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York
| | - Sean M. Bialosuknia
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York
| | - Jessica Stout
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York
| | - Nicholas Mathias
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York
| | - Gillian Eastwood
- Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
- Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | - Alexander T. Ciota
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, New York
| | - Laura D. Kramer
- The Arbovirus Laboratories, Wadsworth Center, New York State Department of Health, Slingerlands, New York
- Department of Biomedical Sciences, State University of New York at Albany School of Public Health, Albany, New York
| | - Philip M. Armstrong
- Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
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23
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Petruff TA, McMillan JR, Shepard JJ, Andreadis TG, Armstrong PM. Increased mosquito abundance and species richness in Connecticut, United States 2001-2019. Sci Rep 2020; 10:19287. [PMID: 33159108 PMCID: PMC7648108 DOI: 10.1038/s41598-020-76231-x] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2020] [Accepted: 10/22/2020] [Indexed: 12/04/2022] Open
Abstract
Historical declines in multiple insect taxa have been documented across the globe in relation to landscape-level changes in land use and climate. However, declines have either not been universally observed in all regions or examined for all species. Because mosquitoes are insects of public health importance, we analyzed a longitudinal mosquito surveillance data set from Connecticut (CT), United States (U.S.) from 2001 to 2019 to identify changes in mosquito community composition over time. We first analyzed annual site-level collections and metrics of mosquito community composition with generalized linear/additive mixed effects models; we also examined annual species-level collections using the same tools. We then examined correlations between statewide collections and weather variables as well as site-level collections and land cover classifications. We found evidence that the average trap night collection of mosquitoes has increased by ~ 60% and statewide species richness has increased by ~ 10% since 2001. Total species richness was highest in the southern portion of CT, likely due to the northward range expansion of multiple species within the Aedes, Anopheles, Culex, and Psorophora genera. How the expansion of mosquito populations in the northeast U.S. will alter mosquito-borne pathogen transmission in the region will require further investigation.
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Affiliation(s)
- Tanya A Petruff
- Center for Vector Biology and Zoonotic Diseases, Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Joseph R McMillan
- Center for Vector Biology and Zoonotic Diseases, Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
| | - John J Shepard
- Center for Vector Biology and Zoonotic Diseases, Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Theodore G Andreadis
- Center for Vector Biology and Zoonotic Diseases, Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
| | - Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, Environmental Sciences, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA
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24
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Kache PA, Eastwood G, Collins-Palmer K, Katz M, Falco RC, Bajwa WI, Armstrong PM, Andreadis TG, Diuk-Wasser MA. Environmental Determinants of Aedes albopictus Abundance at a Northern Limit of Its Range in the United States. Am J Trop Med Hyg 2020; 102:436-447. [PMID: 31833467 PMCID: PMC7008348 DOI: 10.4269/ajtmh.19-0244] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022] Open
Abstract
Aedes albopictus is a vector of arboviruses with high rates of morbidity and mortality. The northern limit of Ae. albopictus in the northeastern United States runs through New York state (NYS) and Connecticut. We present a landscape-level analysis of mosquito abundance measured by daily counts of Ae. albopictus from 338 trap sites in 12 counties during May–September 2017. During the study period, the mean number of Ae. albopictus caught per day of trapping across all sites was 3.21. We constructed four sets of negative binomial generalized linear models to evaluate how trapping methodology, land cover, as well as temperature and precipitation at multiple time intervals influenced Ae. albopictus abundance. Biogents-Sentinel (BGS) traps were 2.78 times as efficient as gravid traps and 1.49 times as efficient as CO2-baited CDC light traps. Greater proportions of low- and medium-intensity development and low proportions of deciduous cover around the trap site were positively associated with increased abundance, as were minimum winter temperature and March precipitation. The cumulative precipitation within a 28-day time window before the date of collection had a nonlinear relationship with abundance, such that greater cumulative precipitation was associated with increased abundance until approximately 70 mm, above which there was a decrease in abundance. We concluded that populations are established in Nassau, Suffolk, and New York City counties in NYS; north of these counties, the species is undergoing population invasion and establishment. We recommend that mosquito surveillance programs monitoring the northward invasion of Ae. albopictus place BGS traps at sites chosen with respect to land cover.
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Affiliation(s)
- Pallavi A Kache
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York City, New York
| | - Gillian Eastwood
- Center for Vector Biology & Zoonotic Diseases, Connecticut Agricultural Experiment Station, New Haven, Connecticut.,Department of Entomology, Virginia Polytechnic Institute and State University, Blacksburg, Virginia
| | - Kaitlin Collins-Palmer
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York City, New York
| | - Marly Katz
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, New York.,The Louis Calder Center-Biological Field Station, Fordham University, Armonk, New York
| | - Richard C Falco
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, New York.,The Louis Calder Center-Biological Field Station, Fordham University, Armonk, New York
| | - Waheed I Bajwa
- Office of Vector Surveillance and Control, New York City Department of Health and Mental Hygiene, New York, New York
| | - Philip M Armstrong
- Center for Vector Biology & Zoonotic Diseases, Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Theodore G Andreadis
- Center for Vector Biology & Zoonotic Diseases, Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Maria A Diuk-Wasser
- Department of Ecology, Evolution, and Environmental Biology, Columbia University, New York City, New York
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25
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Eastwood G, Donnellycolt AK, Shepard JJ, Misencik MJ, Bedoukian R, Cole L, Armstrong PM, Andreadis TG. Evaluation of Novel Trapping Lures for Monitoring Exotic and Native Container-Inhabiting Aedes spp. (Diptera: Culicidae) Mosquitoes. J Med Entomol 2020; 57:534-541. [PMID: 31875224 DOI: 10.1093/jme/tjz200] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Indexed: 06/10/2023]
Abstract
Surveillance for diurnal container-inhabiting mosquitoes such as Aedes albopictus (Skuse), Aedes japonicus japonicus (Theobald), and Aedes triseriatus (Say) have routinely relied on the deployment of multiple trap types, including CO2-baited light traps, gravid traps, oviposition traps, and BG-Sentinel. These trap configurations have met with varying degrees of effectiveness and in many instances likely under-sample these key mosquito vectors. Most recently, the BG-Sentinel trap used in conjunction with the human-scent lure has been largely accepted as the gold-standard for monitoring Ae. albopictus. However, its ability to attract other container-inhabiting Aedes species has not been fully evaluated. During 2018, we tested new scent lures, TrapTech Lure-A and Lure-H (Bedoukian Research, Inc.), using BG-Sentinel traps with CO2 in two regions of Connecticut, Stamford and Hamden, against the BG-Lure. Pooled mosquitoes were additionally screened for arbovirus infection. A total of 47,734 mosquitoes representing 8 genera and 32 species were captured during the study, with the Stamford site deriving on average three times as many mosquitoes per trap, adjusting for sampling effort. Lure-A and Lure-H outperformed the BG-Lure in terms of total numbers, diversity evenness, and the proportion of both Ae. j. japonicus and Ae. triseriatus. There were no significant differences among lures in capturing Ae. albopictus, and in terms of species richness. Fifty-seven isolates of virus (West Nile, Jamestown Canyon, and La Crosse viruses) were obtained during the study, with no significant difference between trap-lure. We highlight both novel lures as effective attractants for use in mosquito surveillance=, which either outperform, or equal, BG-Lure.
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Affiliation(s)
- Gillian Eastwood
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - Andrew K Donnellycolt
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - John J Shepard
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - Michael J Misencik
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
| | | | | | - Philip M Armstrong
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
| | - Theodore G Andreadis
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT
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26
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McMillan JR, Armstrong PM, Andreadis TG. Patterns of mosquito and arbovirus community composition and ecological indexes of arboviral risk in the northeast United States. PLoS Negl Trop Dis 2020; 14:e0008066. [PMID: 32092063 PMCID: PMC7058363 DOI: 10.1371/journal.pntd.0008066] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Revised: 03/05/2020] [Accepted: 01/15/2020] [Indexed: 11/30/2022] Open
Abstract
BACKGROUND In the northeast United States (U.S.), mosquitoes transmit a number of arboviruses, including eastern equine encephalitis, Jamestown Canyon, and West Nile that pose an annual threat to human and animal health. Local transmission of each arbovirus may be driven by the involvement of multiple mosquito species; however, the specificity of these vector-virus associations has not been fully quantified. METHODOLOGY We used long-term surveillance data consistently collected over 18 years to evaluate mosquito and arbovirus community composition in the State of Connecticut (CT) based on land cover classifications and mosquito species-specific natural histories using community ecology approaches available in the R package VEGAN. We then used binomial-error generalized linear mixed effects models to quantify species-specific trends in arbovirus detections. PRIMARY RESULTS The composition of mosquito communities throughout CT varied more among sites than among years, with variation in mosquito community composition among sites explained mostly by a forested-to-developed-land-cover gradient. Arboviral communities varied equally among sites and years, and only developed and forested wetland land cover classifications were associated with the composition of arbovirus detections among sites. Overall, the avian host arboviruses, mainly West Nile and eastern equine encephalitis, displayed the most specific associations among mosquito species and sites, while in contrast, the mammalian host arboviruses (including Cache Valley, Jamestown Canyon, and Potosi) associated with a more diverse mix of mosquito species and were widely distributed throughout CT. CONCLUSIONS We find that avian arboviruses act as vector specialists infecting a few key mosquito species that associate with discrete habitats, while mammalian arboviruses are largely vector generalists infecting a wide diversity of mosquito species and habitats in the region. These distinctions have important implications for the design and implementation of mosquito and arbovirus surveillance programs as well as mosquito control efforts.
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Affiliation(s)
- Joseph R. McMillan
- Environmental Sciences, Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Philip M. Armstrong
- Environmental Sciences, Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Theodore G. Andreadis
- Environmental Sciences, Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
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27
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Armstrong PM, Ehrlich HY, Magalhaes T, Miller MR, Conway PJ, Bransfield A, Misencik MJ, Gloria-Soria A, Warren JL, Andreadis TG, Shepard JJ, Foy BD, Pitzer VE, Brackney DE. Successive blood meals enhance virus dissemination within mosquitoes and increase transmission potential. Nat Microbiol 2019; 5:239-247. [PMID: 31819213 PMCID: PMC7199921 DOI: 10.1038/s41564-019-0619-y] [Citation(s) in RCA: 61] [Impact Index Per Article: 12.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 10/23/2019] [Indexed: 01/07/2023]
Abstract
The recent Zika virus (ZIKV) and chikungunya virus (CHIKV) epidemics highlight the explosive nature of arthropod-borne (arbo)viruses transmitted by Aedes spp. mosquitoes1,2. Vector competence and the extrinsic incubation period (EIP) are two key entomological parameters used to assess the public health risk posed by arboviruses3. These are typically measured empirically by offering mosquitoes an infectious bloodmeal and temporally sampling mosquitoes to determine infection and transmission status. This approach has been used for the better part of a century; however, it does not accurately capture the biology and behavior of many mosquito vectors which refeed frequently (every 2–3 days)4. Here we demonstrate that acquisition of a second non-infectious bloodmeal significantly shortens the EIP of ZIKV-infected Ae. aegypti by enhancing virus dissemination from the mosquito midgut. Similarly, a second bloodmeal increases the competence of this species for dengue virus and CHIKV as well as Ae. albopictus for ZIKV, suggesting that this phenomenon may be common among other virus-vector pairings and that Ae. albopictus might be a more important vector than once thought. Bloodmeal-induced microperforations in the virus-impenetrable basal lamina which surrounds the midgut provide a mechanism for enhanced virus escape. Modeling of these findings reveals that a shortened EIP would result in a significant increase in the basic reproductive number, R0, estimated from experimental data. This helps explain how Ae. aegypti can sustain explosive epidemics like ZIKV despite relatively poor vector competence in single-feed laboratory trials. Together, these data demonstrate a direct and unrecognized link between mosquito feeding behavior, EIP, and vector competence.
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Affiliation(s)
- Philip M Armstrong
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA. .,Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, CT, USA.
| | - Hanna Y Ehrlich
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, CT, USA
| | - Tereza Magalhaes
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Megan R Miller
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Patrick J Conway
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA.,Department of Biomedical Sciences, Quinnipiac University, Hamden, CT, USA
| | - Angela Bransfield
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | - Michael J Misencik
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | - Andrea Gloria-Soria
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | - Joshua L Warren
- Department of Biostatistics, Yale School of Public Health, Yale University, New Haven, CT, USA
| | - Theodore G Andreadis
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA.,Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, CT, USA
| | - John J Shepard
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | - Brian D Foy
- Department of Microbiology, Immunology and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Virginia E Pitzer
- Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, CT, USA
| | - Doug E Brackney
- Center for Vector-Borne and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA. .,Department of Epidemiology of Microbial Diseases, Yale School of Public Health, Yale University, New Haven, CT, USA.
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28
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Keyel AC, Elison Timm O, Backenson PB, Prussing C, Quinones S, McDonough KA, Vuille M, Conn JE, Armstrong PM, Andreadis TG, Kramer LD. Seasonal temperatures and hydrological conditions improve the prediction of West Nile virus infection rates in Culex mosquitoes and human case counts in New York and Connecticut. PLoS One 2019; 14:e0217854. [PMID: 31158250 PMCID: PMC6546252 DOI: 10.1371/journal.pone.0217854] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2019] [Accepted: 05/19/2019] [Indexed: 01/05/2023] Open
Abstract
West Nile virus (WNV; Flaviviridae: Flavivirus) is a widely distributed arthropod-borne virus that has negatively affected human health and animal populations. WNV infection rates of mosquitoes and human cases have been shown to be correlated with climate. However, previous studies have been conducted at a variety of spatial and temporal scales, and the scale-dependence of these relationships has been understudied. We tested the hypothesis that climate variables are important to understand these relationships at all spatial scales. We analyzed the influence of climate on WNV infection rate of mosquitoes and number of human cases in New York and Connecticut using Random Forests, a machine learning technique. During model development, 66 climate-related variables based on temperature, precipitation and soil moisture were tested for predictive skill. We also included 20-21 non-climatic variables to account for known environmental effects (e.g., land cover and human population), surveillance related information (e.g., relative mosquito abundance), and to assess the potential explanatory power of other relevant factors (e.g., presence of wastewater treatment plants). Random forest models were used to identify the most important climate variables for explaining spatial-temporal variation in mosquito infection rates (abbreviated as MLE). The results of the cross-validation support our hypothesis that climate variables improve the predictive skill for MLE at county- and trap-scales and for human cases at the county-scale. Of the climate-related variables selected, mean minimum temperature from July-September was selected in all analyses, and soil moisture was selected for the mosquito county-scale analysis. Models demonstrated predictive skill, but still over- and under-estimated WNV MLE and numbers of human cases. Models at fine spatial scales had lower absolute errors but had greater errors relative to the mean infection rates.
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Affiliation(s)
- Alexander C. Keyel
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
- Department of Atmospheric and Environmental Sciences, University at Albany, SUNY, Albany, NY, United States of America
| | - Oliver Elison Timm
- Department of Atmospheric and Environmental Sciences, University at Albany, SUNY, Albany, NY, United States of America
| | - P. Bryon Backenson
- Bureau of Communicable Disease Control, New York State Department of Health, Albany, NY, United States of America
| | - Catharine Prussing
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY, United States of America
| | - Sarah Quinones
- Department of Atmospheric and Environmental Sciences, University at Albany, SUNY, Albany, NY, United States of America
| | - Kathleen A. McDonough
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
- Department of Biomedical Sciences, University at Albany, SUNY, Albany, NY, United States of America
| | - Mathias Vuille
- Department of Atmospheric and Environmental Sciences, University at Albany, SUNY, Albany, NY, United States of America
| | - Jan E. Conn
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
| | - Philip M. Armstrong
- Center for Vector Biology & Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experimental Station, New Haven, CT, United States of America
| | - Theodore G. Andreadis
- Center for Vector Biology & Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experimental Station, New Haven, CT, United States of America
| | - Laura D. Kramer
- Division of Infectious Disease, Wadsworth Center, New York State Department of Health, Albany, NY, United States of America
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29
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Yang F, Chan K, Marek PE, Armstrong PM, Liu P, Bova JE, Bernick JN, McMillan BE, Weidlich BG, Paulson SL. Cache Valley Virus in Aedes japonicus japonicus Mosquitoes, Appalachian Region, United States. Emerg Infect Dis 2019; 24:553-557. [PMID: 29460762 PMCID: PMC5823325 DOI: 10.3201/eid2403.161275] [Citation(s) in RCA: 22] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
Abstract
We detected Cache Valley virus in Aedes japonicus, a widely distributed invasive mosquito species, in an Appalachian forest in the United States. The forest contained abundant white-tailed deer, a major host of the mosquito and virus. Vector competence trials indicated that Ae. j. japonicus mosquitoes can transmit this virus in this region.
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Weger-Lucarelli J, Rückert C, Grubaugh ND, Misencik MJ, Armstrong PM, Stenglein MD, Ebel GD, Brackney DE. Adventitious viruses persistently infect three commonly used mosquito cell lines. Virology 2018; 521:175-180. [PMID: 29957338 DOI: 10.1016/j.virol.2018.06.007] [Citation(s) in RCA: 26] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2018] [Revised: 06/12/2018] [Accepted: 06/13/2018] [Indexed: 11/26/2022]
Abstract
Mosquito cell lines have been used extensively in research to isolate and propagate arthropod-borne viruses and understand virus-vector interactions. Despite their utility as an in vitro tool, these cell lines are poorly defined and may harbor insect-specific viruses. Accordingly, we screened four commonly-used mosquito cell lines, C6/36 and U4.4 cells from Aedes albopictus, Aag2 cells from Aedes aegypti, and Hsu cells from Culex quinquefasciatus, for the presence of adventitious (i.e. exogenous) viruses. All four cell lines stained positive for double-stranded RNA, indicative of RNA virus replication. We subsequently identified viruses infecting Aag2, U4.4 and Hsu cell lines using untargeted next-generation sequencing, but not C6/36 cells. PCR confirmation revealed that these sequences stem from active viral replication and/or integration into the cellular genome. Our results show that these commonly-used mosquito cell lines are persistently-infected with several viruses. This finding may be critical to interpreting data generated in these systems.
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Affiliation(s)
- James Weger-Lucarelli
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Claudia Rückert
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Nathan D Grubaugh
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Michael J Misencik
- The Connecticut Agricultural Experiment Station, Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, New Haven, CT, USA
| | - Philip M Armstrong
- The Connecticut Agricultural Experiment Station, Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, New Haven, CT, USA
| | - Mark D Stenglein
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Gregory D Ebel
- Department of Microbiology, Immunology, and Pathology, Colorado State University, Fort Collins, CO, USA
| | - Doug E Brackney
- The Connecticut Agricultural Experiment Station, Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, New Haven, CT, USA.
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Gloria-Soria A, Armstrong PM, Powell JR, Turner PE. Infection rate of Aedes aegypti mosquitoes with dengue virus depends on the interaction between temperature and mosquito genotype. Proc Biol Sci 2018; 284:rspb.2017.1506. [PMID: 28978730 DOI: 10.1098/rspb.2017.1506] [Citation(s) in RCA: 32] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2017] [Accepted: 09/04/2017] [Indexed: 11/12/2022] Open
Abstract
Dengue fever is the most prevalent arthropod-transmitted viral disease worldwide, with endemic transmission restricted to tropical and subtropical regions of different temperature profiles. Temperature is epidemiologically relevant because it affects dengue infection rates in Aedes aegypti mosquitoes, the major vector of the dengue virus (DENV). Aedes aegypti populations are also known to vary in competence for different DENV genotypes. We assessed the effects of mosquito and virus genotype on DENV infection in the context of temperature by challenging Ae. aegypti from two locations in Vietnam, which differ in temperature regimes, with two isolates of DENV-2 collected from the same two localities, followed by incubation at 25, 27 or 32°C for 10 days. Genotyping of the mosquito populations and virus isolates confirmed that each group was genetically distinct. Extrinsic incubation temperature (EIT) and DENV-2 genotype had a direct effect on the infection rate, consistent with previous studies. However, our results show that the EIT impacts the infection rate differently in each mosquito population, indicating a genotype by environment interaction. These results suggest that the magnitude of DENV epidemics may not only depend on the virus and mosquito genotypes present, but also on how they interact with local temperature. This information should be considered when estimating vector competence of local and introduced mosquito populations during disease risk evaluation.
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Affiliation(s)
- A Gloria-Soria
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St. PO Box 208106, New Haven, CT 06520-8106, USA
| | - P M Armstrong
- The Connecticut Agricultural Experiment Station, 123 Huntington St. PO Box 1106, New Haven, CT 06504, USA
| | - J R Powell
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St. PO Box 208106, New Haven, CT 06520-8106, USA
| | - P E Turner
- Department of Ecology and Evolutionary Biology, Yale University, 165 Prospect St. PO Box 208106, New Haven, CT 06520-8106, USA.,Program in Microbiology, Yale School of Medicine, New Haven, CT 06520, USA
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Anderson JF, Armstrong PM, Misencik MJ, Bransfield AB, Andreadis TG, Molaei G. Seasonal Distribution, Blood-Feeding Habits, and Viruses of Mosquitoes in an Open-Faced Quarry in Connecticut, 2010 and 2011. J Am Mosq Control Assoc 2018; 34:1-10. [PMID: 31442119 DOI: 10.2987/17-6707.1] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Seasonal abundance of mosquitoes, their viruses, and blood-feeding habits were determined at an open-faced quarry in North Branford, CT, in 2010 and 2011. This unique habitat had not previously been sampled for mosquitoes and mosquito-borne viruses. Thirty species of mosquitoes were identified from 41,719 specimens collected. Coquillettidia perturbans, Aedes trivittatus, and Ae. vexans were the most abundant species and represented 34.5%, 17.7%, and 14.8% of the totals, respectively. Jamestown Canyon virus was isolated from 6 species of mosquitoes collected from mid-June through July: Cq. perturbans (3 pools), Ae. cantator (3), Ae. trivittatus (2), Ae. aurifer (1), Ae. excrucians (1), and Culex pipiens (1). West Nile virus was cultured from 8 pools of Cx. pipiens and from 1 pool of Culiseta melanura collected from mid-August through late September. Cache Valley virus was isolated from 4 species of mosquitoes in 3 genera from about mid-August through late September 2011: Cq. perturbans (5 pools), Ae. trivittatus (2), Anopheles punctipennis (1), and An. quadrimaculatus (1). Nine different mammalian hosts were identified as sources of blood for 13 species of mosquitoes. White-tailed deer, Odocoileus virginianus, were the most common mammalian hosts (90.8%), followed by raccoon, Procyon lotor (3.1%), coyote, Canis latrans (2.4%), and human, Homo sapiens (1.2%). Exclusive mammalian blood-feeding mosquitoes included: Ae. canadensis, Ae. cantator, Ae. excrucians, Ae. japonicus, Ae. vexans, An. punctipennis, and Cx. salinarius. Fourteen species of birds, mostly Passeriformes, were identified as sources of blood from 6 mosquito species. Five species that fed on mammals (Ae. thibaulti, Ae. trivittatus, Ae. cinereus, Cq. perturbans, and Cx. pipiens) also fed on birds.
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Cahill ME, Yao Y, Nock D, Armstrong PM, Andreadis TG, Diuk-Wasser MA, Montgomery RR. West Nile Virus Seroprevalence, Connecticut, USA, 2000-2014. Emerg Infect Dis 2018; 23:708-710. [PMID: 28322715 PMCID: PMC5367428 DOI: 10.3201/eid2304.161669] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022] Open
Abstract
West Nile virus (WNV) infection is mainly asymptomatic but can be severe in elderly persons. As part of studies on immunity and aging in Connecticut, USA, we detected WNV seroconversion in 8.5% of nonimmunosuppressed and 16.8% of immunosuppressed persons. Age was not a significant seroconversion factor. Our findings suggest that immune factors affect seroconversion.
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Skaff NK, Armstrong PM, Andreadis TG, Cheruvelil KS. Wetland characteristics linked to broad-scale patterns in Culiseta melanura abundance and eastern equine encephalitis virus infection. Parasit Vectors 2017; 10:501. [PMID: 29047412 PMCID: PMC5648514 DOI: 10.1186/s13071-017-2482-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2017] [Accepted: 10/13/2017] [Indexed: 01/09/2023] Open
Abstract
BACKGROUND Eastern equine encephalitis virus (EEEV) is an expanding mosquito-borne threat to humans and domestic animal populations in the northeastern United States. Outbreaks of EEEV are challenging to predict due to spatial and temporal uncertainty in the abundance and viral infection of Cs. melanura, the principal enzootic vector. EEEV activity may be closely linked to wetlands because they provide essential habitat for mosquito vectors and avian reservoir hosts. However, wetlands are not homogeneous and can vary by vegetation, connectivity, size, and inundation patterns. Wetlands may also have different effects on EEEV transmission depending on the assessed spatial scale. We investigated associations between wetland characteristics and Cs. melanura abundance and infection with EEEV at multiple spatial scales in Connecticut, USA. RESULTS Our findings indicate that wetland vegetative characteristics have strong associations with Cs. melanura abundance. Deciduous and evergreen forested wetlands were associated with higher Cs. melanura abundance, likely because these wetlands provide suitable subterranean habitat for Cs. melanura development. In contrast, Cs. melanura abundance was negatively associated with emergent and scrub/shrub wetlands, and wetland connectivity to streams. These relationships were generally strongest at broad spatial scales. Additionally, the relationships between wetland characteristics and EEEV infection in Cs. melanura were generally weak. However, Cs. melanura abundance was strongly associated with EEEV infection, suggesting that wetland-associated changes in abundance may be indirectly linked to EEEV infection in Cs. melanura. Finally, we found that wet hydrological conditions during the transmission season and during the fall/winter preceding the transmission season were associated with higher Cs. melanura abundance and EEEV infection, indicating that wet conditions are favorable for EEEV transmission. CONCLUSIONS These results expand the broad-scale understanding of the effects of wetlands on EEEV transmission and help to reduce the spatial and temporal uncertainty associated with EEEV outbreaks.
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Affiliation(s)
- Nicholas K Skaff
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA. .,Ecology, Evolutionary Biology & Behavior Program, Michigan State University, East Lansing, MI, USA.
| | - Philip M Armstrong
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | - Theodore G Andreadis
- Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, New Haven, CT, USA
| | - Kendra S Cheruvelil
- Department of Fisheries and Wildlife, Michigan State University, East Lansing, MI, USA.,Lyman Briggs College, Michigan State University, East Lansing, MI, USA
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Armstrong PM, Andreadis TG, Shepard JJ, Thomas MC. Northern range expansion of the Asian tiger mosquito (Aedes albopictus): Analysis of mosquito data from Connecticut, USA. PLoS Negl Trop Dis 2017; 11:e0005623. [PMID: 28545111 PMCID: PMC5451134 DOI: 10.1371/journal.pntd.0005623] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Revised: 05/31/2017] [Accepted: 05/04/2017] [Indexed: 11/18/2022] Open
Abstract
Background The Asian tiger mosquito (Aedes albopictus) is an invasive species and important arbovirus vector that was introduced into the U.S. in the 1980's where it continues to expand its range. Winter temperature is an important constraint to its northward expansion, with potential range limits located between the 0° and -5°C mean cold month isotherm. Connecticut is located within this climatic zone and therefore, Ae. albopictus was monitored statewide to assess its northern range expansion and to delineate where populations can stably persist. Methodology/Principal findings Ae. albopictus females were monitored at fixed trapping sites throughout Connecticut from June-October over a 20-year period, 1997–2016. In addition, Ae. albopictus larvae and pupae were collected from tire habitats and tires were retrieved from the field in the spring and flooded to evaluate overwintering success of hatching larvae. Ae. albopictus was first detected during statewide surveillance when a single adult female was collected in 2006. This species was not collected again until 2010 and was subsequently detected each successive year with increasing abundance and distribution except following the unusually cold winters of 2014 and 2015. Ae. albopictus mosquitoes were most abundant in urban and suburban locations along the southwestern shoreline of Connecticut; however, single specimens were occasionally detected in central parts of the state. Field-collected females were also screened for arbovirus infection yielding two isolations of Cache Valley virus and one isolation of West Nile virus, highlighting the threat posed by this mosquito. Ae. albopictus overwintered in Connecticut under mild winter conditions as shown by recovery of hatched larvae from field collected tires in spring and by early season detection of larvae and pupae. Conclusions/Significance This study documents the establishment and expansion of Ae. albopictus at the northern boundary of its range in the northeastern U.S. and provides a baseline for monitoring the future spread of this species anticipated under climate change. The Asian tiger mosquito (Aedes albopictus) is a highly invasive species and an important disease vector that is undergoing rapid range expansion in many countries including the U.S. Winter temperature is an important limit to its northward expansion with Connecticut situated near the northern boundary of its potential range. In this study, we sampled mosquitoes at fixed trapping sites located statewide to track the establishment and range expansion of Ae. albopictus in this region. In addition, mosquito larvae were monitored in tire habitats to evaluate overwintering success of local populations. From this effort, we describe the initial detection of Ae. albopictus in 2006, its annual reemergence and population expansion in southwestern Connecticut from 2010–2016, and its local overwintering under mild winter conditions. Together, this study documents population changes in Ae. albopictus at the northern boundary of its range and provides a baseline for monitoring future range expansion anticipated under climate change.
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Affiliation(s)
- Philip M. Armstrong
- Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
- * E-mail:
| | - Theodore G. Andreadis
- Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - John J. Shepard
- Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Michael C. Thomas
- Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
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Grubaugh ND, Rückert C, Armstrong PM, Bransfield A, Anderson JF, Ebel GD, Brackney DE. Transmission bottlenecks and RNAi collectively influence tick-borne flavivirus evolution. Virus Evol 2016; 2:vew033. [PMID: 28058113 PMCID: PMC5210029 DOI: 10.1093/ve/vew033] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Arthropod-borne RNA viruses exist within hosts as heterogeneous populations of viral variants and, as a result, possess great genetic plasticity. Understanding the micro-evolutionary forces shaping these viruses can provide insights into how they emerge, adapt, and persist in new and changing ecological niches. While considerable attention has been directed toward studying the population dynamics of mosquito-borne viruses, little is known about tick-borne virus populations. Therefore, using a mouse and Ixodes scapularis tick transmission model, we examined Powassan virus (POWV; Flaviviridae, Flavivirus) populations in and between both the vertebrate host and arthropod vector. We found that genetic bottlenecks, RNAi-mediated diversification, and selective constraints collectively influence POWV evolution. Together, our data provide a mechanistic explanation for the slow, long-term evolutionary trends of POWV, and suggest that all arthropod-borne viruses encounter similar selective pressures at the molecular level (i.e. RNAi), yet evolve much differently due to their unique rates and modes of transmission.
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Affiliation(s)
- Nathan D Grubaugh
- Department of Microbiology Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, CO, USA
| | - Claudia Rückert
- Department of Microbiology Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, CO, USA
| | - Philip M Armstrong
- The Connecticut Agricultural Experiment Station, Center for Vector Biology and Zoonotic Diseases, New Haven, CT, USA
| | - Angela Bransfield
- The Connecticut Agricultural Experiment Station, Center for Vector Biology and Zoonotic Diseases, New Haven, CT, USA
| | - John F Anderson
- The Connecticut Agricultural Experiment Station, Center for Vector Biology and Zoonotic Diseases, New Haven, CT, USA
| | - Gregory D Ebel
- Department of Microbiology Immunology and Pathology, College of Veterinary Medicine and Biomedical Sciences, Fort Collins, CO, USA
| | - Doug E Brackney
- The Connecticut Agricultural Experiment Station, Center for Vector Biology and Zoonotic Diseases, New Haven, CT, USA
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Andreadis TG, Armstrong PM, Anderson JF, Main AJ. Spatial-temporal analysis of Cache Valley virus (Bunyaviridae: Orthobunyavirus) infection in anopheline and culicine mosquitoes (Diptera: Culicidae) in the northeastern United States, 1997-2012. Vector Borne Zoonotic Dis 2016; 14:763-73. [PMID: 25325321 DOI: 10.1089/vbz.2014.1669] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Cache Valley virus (CVV) is a mosquito-borne bunyavirus (family Bunyaviridae, genus Orthobunyavirus) that is enzootic throughout much of North and Central America. White-tailed deer (Odocoileus virginianus) have been incriminated as important reservoir and amplification hosts. CVV has been found in a diverse array of mosquito species, but the principal vectors are unknown. A 16-year study was undertaken to identify the primary mosquito vectors in Connecticut, quantify seasonal prevalence rates of infection, and define the spatial geographic distribution of CVV in the state as a function of land use and white-tailed deer populations, which have increased substantially over this period. CVV was isolated from 16 mosquito species in seven genera, almost all of which were multivoltine and mammalophilic. Anopheles (An.) punctipennis was incriminated as the most consistent and likely vector in this region on the basis of yearly isolation frequencies and the spatial geographic distribution of infected mosquitoes. Other species exhibiting frequent temporal and moderate spatial geographic patterns of virus isolation within the state included Ochlerotatus (Oc.) trivittatus, Oc. canadensis, Aedes (Ae.) vexans, and Ae. cinereus. New isolation records for CVV were established for An. walkeri, Culiseta melanura, and Oc. cantator. Other species from which CVV was isolated included An. quadrimaculatus, Coquillettidia perturbans, Culex salinarius, Oc. japonicus, Oc. sollicitans, Oc. taeniorhynchus, Oc. triseriatus, and Psorophora ferox. Mosquitoes infected with CVV were equally distributed throughout urban, suburban, and rural locales, and infection rates were not directly associated with the localized abundance of white-tailed deer, possibly due to their saturation throughout the region. Virus activity in mosquitoes was episodic with no consistent pattern from year-to-year, and fluctuations in yearly seasonal infection rates did not appear to be directly impacted by overall mosquito abundance. Virus infection in mosquitoes occurred late in the season that mostly extended from mid-August through September, when adult mosquito populations were visibly declining and were comparatively low. Findings argue for a limited role for vertical transmission for the perpetuation of CVV as occurs with other related bunyaviruses.
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Affiliation(s)
- Theodore G Andreadis
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station , New Haven, Connecticut
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Misencik MJ, Grubaugh ND, Andreadis TG, Ebel GD, Armstrong PM. Isolation of a Novel Insect-Specific Flavivirus from Culiseta melanura in the Northeastern United States. Vector Borne Zoonotic Dis 2016; 16:181-90. [PMID: 26807512 DOI: 10.1089/vbz.2015.1889] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The genus Flavivirus includes a number of newly recognized viruses that infect and replicate only within mosquitoes. To determine whether insect-specific flaviviruses (ISFs) may infect Culiseta (Cs.) melanura mosquitoes, we screened pools of field-collected mosquitoes for virus infection by RT-PCR targeting conserved regions of the NS5 gene. NS5 nucleotide sequences amplified from Cs. melanura pools were genetically similar to other ISFs and most closely matched Calbertado virus from Culex tarsalis, sharing 68.7% nucleotide and 76.1% amino acid sequence identity. The complete genome of one virus isolate was sequenced to reveal a primary open reading frame (ORF) encoding a viral polyprotein characteristic of the genus Flavivirus. Phylogenetic analysis showed that this virus represents a distinct evolutionary lineage that belongs to the classical ISF group. The virus was detected solely in Cs. melanura pools, occurred in sampled populations from Connecticut, New York, New Hampshire, and Maine, and infected both adult and larval stages of the mosquito. Maximum likelihood estimate infection rates (MLE-IR) were relatively stable in overwintering Cs. melanura larvae collected monthly from November of 2012 through May of 2013 (MLE-IR = 0.7-2.1/100 mosquitoes) and in host-seeking females collected weekly from June through October of 2013 (MLE-IR = 3.8-11.5/100 mosquitoes). Phylogenetic analysis of viral sequences revealed limited genetic variation that lacked obvious geographic structure among strains in the northeastern United States. This new virus is provisionally named Culiseta flavivirus on the basis of its host association with Cs. melanura.
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Affiliation(s)
- Michael J Misencik
- 1 Center for Vector Biology and Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Nathan D Grubaugh
- 2 Arthropod-Borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology, and Pathology, Colorado State University , Fort Collins, Colorado
| | - Theodore G Andreadis
- 1 Center for Vector Biology and Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Gregory D Ebel
- 2 Arthropod-Borne and Infectious Diseases Laboratory, Department of Microbiology, Immunology, and Pathology, Colorado State University , Fort Collins, Colorado
| | - Philip M Armstrong
- 1 Center for Vector Biology and Zoonotic Diseases , The Connecticut Agricultural Experiment Station, New Haven, Connecticut
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Molaei G, Thomas MC, Muller T, Medlock J, Shepard JJ, Armstrong PM, Andreadis TG. Dynamics of Vector-Host Interactions in Avian Communities in Four Eastern Equine Encephalitis Virus Foci in the Northeastern U.S. PLoS Negl Trop Dis 2016; 10:e0004347. [PMID: 26751704 PMCID: PMC4713425 DOI: 10.1371/journal.pntd.0004347] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2015] [Accepted: 12/09/2015] [Indexed: 11/18/2022] Open
Abstract
BACKGROUND Eastern equine encephalitis (EEE) virus (Togaviridae, Alphavirus) is a highly pathogenic mosquito-borne zoonosis that is responsible for occasional outbreaks of severe disease in humans and equines, resulting in high mortality and neurological impairment in most survivors. In the past, human disease outbreaks in the northeastern U.S. have occurred intermittently with no apparent pattern; however, during the last decade we have witnessed recurring annual emergence where EEE virus activity had been historically rare, and expansion into northern New England where the virus had been previously unknown. In the northeastern U.S., EEE virus is maintained in an enzootic cycle involving the ornithophagic mosquito, Culiseta melanura, and wild passerine (perching) birds in freshwater hardwood swamps. However, the identity of key avian species that serve as principal virus reservoir and amplification hosts has not been established. The efficiency with which pathogen transmission occurs within an avian community is largely determined by the relative reservoir competence of each species and by ecological factors that influence contact rates between these avian hosts and mosquito vectors. METHODOLOGY AND PRINCIPLE FINDINGS Contacts between vector mosquitoes and potential avian hosts may be directly quantified by analyzing the blood meal contents of field-collected specimens. We used PCR-based molecular methods and direct sequencing of the mitochondrial cytochrome b gene for profiling of blood meals in Cs. melanura, in an effort to quantify its feeding behavior on specific vertebrate hosts, and to infer epidemiologic implications in four historic EEE virus foci in the northeastern U.S. Avian point count surveys were conducted to determine spatiotemporal host community composition. Of 1,127 blood meals successfully identified to species level, >99% of blood meals were from 65 avian hosts in 27 families and 11 orders, and only seven were from mammalian hosts representing three species. We developed an empirically informed mathematical model for EEE virus transmission using Cs. melanura abundance and preferred and non-preferred avian hosts. To our knowledge this is the first mathematical model for EEE virus, a pathogen with many potential hosts, in the northeastern U.S. We measured strong feeding preferences for a number of avian species based on the proportion of mosquito blood meals identified from these bird species in relation to their observed frequencies. These included: American Robin, Tufted Titmouse, Common Grackle, Wood Thrush, Chipping Sparrow, Black-capped Chickadee, Northern Cardinal, and Warbling Vireo. We found that these bird species, most notably Wood Thrush, play a dominant role in supporting EEE virus amplification. It is also noteworthy that the competence of some of the aforementioned avian species for EEE virus has not been established. Our findings indicate that heterogeneity induced by mosquito host preference, is a key mediator of the epizootic transmission of vector-borne pathogens. CONCLUSION AND SIGNIFICANCE Detailed knowledge of the vector-host interactions of mosquito populations in nature is essential for evaluating their vectorial capacity and for assessing the role of individual vertebrates as reservoir hosts involved in the maintenance and amplification of zoonotic agents of human diseases. Our study clarifies the host associations of Cs. melanura in four EEE virus foci in the northeastern U.S., identifies vector host preferences as the most important transmission parameter, and quantifies the contribution of preference-induced contact heterogeneity to enzootic transmission. Our study identifies Wood Thrush, American Robin and a few avian species that may serve as superspreaders of EEE virus. Our study elucidates spatiotemporal host species utilization by Cs. melanura in relation to avian host community. This research provides a basis to better understand the involvement of Cs. melanura and avian hosts in the transmission and ecology of EEE virus and the risk of human infection in virus foci.
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Affiliation(s)
- Goudarz Molaei
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Michael C. Thomas
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Tim Muller
- Department of Mathematics, College of Science, Oregon State University, Corvallis, Oregon, United States of America
| | - Jan Medlock
- Department of Biomedical sciences, College of Veterinary Medicine, Oregon State University, Corvallis, Oregon, United States of America
| | - John J. Shepard
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Philip M. Armstrong
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Theodore G. Andreadis
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
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Molaei G, Armstrong PM, Graham AC, Kramer LD, Andreadis TG. Insights into the recent emergence and expansion of eastern equine encephalitis virus in a new focus in the Northern New England USA. Parasit Vectors 2015; 8:516. [PMID: 26453283 PMCID: PMC4600208 DOI: 10.1186/s13071-015-1145-2] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2015] [Accepted: 10/03/2015] [Indexed: 01/29/2023] Open
Abstract
BACKGROUND Eastern equine encephalomyelitis virus (EEEV) causes a highly pathogenic zoonosis that circulates in an enzootic cycle involving the ornithophagic mosquito, Culiseta melanura, and wild passerine birds in freshwater hardwood swamps in the northeastern U.S. Epidemic/epizootic transmission to humans/equines typically occurs towards the end of the transmission season and is generally assumed to be mediated by locally abundant and contiguous mammalophagic "bridge vector" mosquitoes. METHODS Engorged mosquitoes were collected using CDC light, resting box, and gravid traps during epidemic transmission of EEEV in 2012 in Addison and Rutland counties, Vermont. Mosquitoes were identified to species and blood meal analysis performed by sequencing mitochondrial cytochrome b gene polymerase chain reaction products. Infection status with EEEV in mosquitoes was determined using cell culture and RT-PCR assays, and all viral isolates were sequenced and compared to other EEEV strains by phylogenetic analysis. RESULTS The host choices of 574 engorged mosquitoes were as follows: Cs. melanura (n = 331, 94.3 % avian-derived, 5.7 % mammalian-derived); Anopheles quadrimaculatus (n = 164, 3.0 % avian, 97.0 % mammalian); An. punctipennis (n = 56, 7.2 % avian, 92.8 % mammalian), Aedes vexans (n = 9, 22.2 % avian, 77.8 % mammalian); Culex pipiens s.l. n = 6, 100 % avian); Coquillettidia perturbans (n = 4, 25.0 % avian, 75.0 % mammalian); and Cs. morsitans (n = 4, 100 % avian). A seasonal shift in blood feeding by Cs. melanura from Green Heron towards other avian species was observed. EEEV was successfully isolated from blood-fed Cs. melanura and analyzed by phylogenetic analysis. Vermont strains from 2012 clustered with viral strains previously isolated in Virginia yet were genetically distinct from an earlier EEEV isolate from Vermont during 2011. CONCLUSIONS Culiseta melanura acquired blood meals primarily from birds and focused feeding activity on several competent species capable of supporting EEEV transmission. Culiseta melanura also occasionally obtained blood meals from mammalian hosts including humans. This mosquito species serves as the primary vector of EEEV among wild bird species, but also is capable of occasionally contributing to epidemic/epizootic transmission of EEEV to humans/equines. Other mosquito species including Cq. perturbans that feed more opportunistically on both avian and mammalian hosts may be important in epidemic/epizootic transmission under certain conditions. Phylogenetic analyses suggest that EEEV was independently introduced into Vermont on at least two separate occasions.
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Affiliation(s)
- Goudarz Molaei
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
| | - Philip M Armstrong
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
| | - Alan C Graham
- Vermont Agency of Agriculture, 322 Industrial Lane, Barre, VT, 05641, USA.
| | - Laura D Kramer
- Wadsworth Center, New York State Department of Health, 5668 State Farm Rd, Slingerlands, NY, 12159, USA.
| | - Theodore G Andreadis
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, 123 Huntington Street, New Haven, CT, 06511, USA.
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Molaei G, Armstrong PM, Abadam CF, Akaratovic KI, Kiser JP, Andreadis TG. Vector-Host Interactions of Culiseta melanura in a Focus of Eastern Equine Encephalitis Virus Activity in Southeastern Virginia. PLoS One 2015; 10:e0136743. [PMID: 26327226 PMCID: PMC4556703 DOI: 10.1371/journal.pone.0136743] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2015] [Accepted: 08/07/2015] [Indexed: 02/08/2023] Open
Abstract
Eastern equine encephalitis virus (EEEV) causes a highly pathogenic mosquito-borne zoonosis that is responsible for sporadic outbreaks of severe illness in humans and equines in the eastern USA. Culiseta (Cs.) melanura is the primary vector of EEEV in most geographic regions but its feeding patterns on specific avian and mammalian hosts are largely unknown in the mid-Atlantic region. The objectives of our study were to: 1) identify avian hosts of Cs. melanura and evaluate their potential role in enzootic amplification of EEEV, 2) assess spatial and temporal patterns of virus activity during a season of intense virus transmission, and 3) investigate the potential role of Cs. melanura in epidemic/epizootic transmission of EEEV to humans and equines. Accordingly, we collected mosquitoes at 55 sites in Suffolk, Virginia in 2013, and identified the source of blood meals in engorged mosquitoes by nucleotide sequencing PCR products of the mitochondrial cytochrome b gene. We also examined field-collected mosquitoes for evidence of infection with EEEV using Vector Test, cell culture, and PCR. Analysis of 188 engorged Cs. melanura sampled from April through October 2013 indicated that 95.2%, 4.3%, and 0.5% obtained blood meals from avian, mammalian, and reptilian hosts, respectively. American Robin was the most frequently identified host for Cs. melanura (42.6% of blood meals) followed by Northern Cardinal (16.0%), European Starling (11.2%), Carolina Wren (4.3%), and Common Grackle (4.3%). EEEV was detected in 106 mosquito pools of Cs. melanura, and the number of virus positive pools peaked in late July with 22 positive pools and a Maximum Likelihood Estimation (MLE) infection rate of 4.46 per 1,000 mosquitoes. Our findings highlight the importance of Cs. melanura as a regional EEEV vector based on frequent feeding on virus-competent bird species. A small proportion of blood meals acquired from mammalian hosts suggests the possibility that this species may occasionally contribute to epidemic/epizootic transmission of EEEV.
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Affiliation(s)
- Goudarz Molaei
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Philip M. Armstrong
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
| | - Charles F. Abadam
- Suffolk Mosquito Control, Department of Public Works, Suffolk, Virginia, United States of America
| | - Karen I. Akaratovic
- Suffolk Mosquito Control, Department of Public Works, Suffolk, Virginia, United States of America
| | - Jay P. Kiser
- Suffolk Mosquito Control, Department of Public Works, Suffolk, Virginia, United States of America
| | - Theodore G. Andreadis
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut, United States of America
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Armstrong PM, Andreadis TG, Anderson JF. Emergence of a new lineage of Cache Valley virus (Bunyaviridae: Orthobunyavirus) in the Northeastern United States. Am J Trop Med Hyg 2015; 93:11-7. [PMID: 25962774 DOI: 10.4269/ajtmh.15-0132] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/13/2015] [Accepted: 03/28/2015] [Indexed: 11/07/2022] Open
Abstract
Cache Valley virus (CVV; Family Bunyavidae, Genus Orthobunyavirus) is a mosquito-borne zoonosis that frequently infects humans and livestock in North and Central America. In the northeastern United States, CVV transmission is unpredictable from year-to-year and may derive from the periodic extinction and reintroduction of new virus strains into this region. To evaluate this possibility, we sequenced and analyzed numerous CVV isolates sampled in Connecticut during an 18-year period to determine how the virus population may change over time. Phylogenetic analyses showed the establishment of a new viral lineage during 2010 that became dominant by 2014 and appears to have originated from southern Mexico. CVV strains from Connecticut also grouped into numerous sub-clades within each lineage that included viruses from other U.S. states and Canada. We did not observe the development and stable persistence of local viral clades in Connecticut, which may reflect the episodic pattern of CVV transmission. Together, our data support the emergence of a new lineage of CVV in the northeastern United States and suggest extensive dispersal of viral strains in North America.
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Affiliation(s)
- Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - Theodore G Andreadis
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
| | - John F Anderson
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut
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Anderson JF, Main AJ, Armstrong PM, Andreadis TG, Ferrandino FJ. Arboviruses in North Dakota, 2003-2006. Am J Trop Med Hyg 2015; 92:377-93. [PMID: 25487728 PMCID: PMC4347345 DOI: 10.4269/ajtmh.14-0291] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2014] [Accepted: 11/02/2014] [Indexed: 11/07/2022] Open
Abstract
To investigate arbovirus transmission in North Dakota, we collected and screened mosquitoes for viral infection by Vero cell culture assay. Seven viruses were isolated from 13 mosquito species. Spatial and temporal distributions of the important vectors of West Nile virus (WNV), Cache Valley virus, Jamestown Canyon virus (JCV), and trivittatus virus are reported. Snowshoe hare virus, Potosi virus, and western equine encephalomyelitis virus were also isolated. The risks of Culex tarsalis and Aedes vexans transmitting WNV to humans were 61.4% and 34.0% in 2003-2006, respectively, but in 2003 when the largest epidemic was reported, risks for Ae. vexans and Cx. tarsalis in Cass County were 73.6% and 23.9%, respectively. Risk of humans acquiring an infectious bite was greatest from about the second week of July through most of August. West Nile virus sequences were of the WN02 genotype. Most JCV strains belonged to a single clade of genetically related strains. Cache Valley virus and JCV were prevalent during August and early September and during July and August, respectively.
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Affiliation(s)
- John F Anderson
- Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut; Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases; Department of Plant Pathology and Ecology
| | - Andy J Main
- Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut; Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases; Department of Plant Pathology and Ecology
| | - Philip M Armstrong
- Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut; Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases; Department of Plant Pathology and Ecology
| | - Theodore G Andreadis
- Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut; Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases; Department of Plant Pathology and Ecology
| | - Francis J Ferrandino
- Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut; Department of Environmental Sciences, Center for Vector Biology and Zoonotic Diseases; Department of Plant Pathology and Ecology
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Armstrong PM, Anderson JF, Farajollahi A, Healy SP, Unlu I, Crepeau TN, Gaugler R, Fonseca DM, Andreadis TG. Isolations of Cache Valley virus from Aedes albopictus (Diptera: Culicidae) in New Jersey and evaluation of its role as a regional arbovirus vector. J Med Entomol 2013; 50:1310-1314. [PMID: 24843937 DOI: 10.1603/me13099] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
The Asian tiger mosquito, Aedes albopictus (Skuse), is an invasive species and a major pest problem in urban and suburban locales in New Jersey. To assess its potential role as an arbovirus vector, we sampled Ae. albopictus from two New Jersey counties over a 3-yr period and estimated the prevalence of virus infection by Vero cell culture and reverse transcription-polymerase chain reaction assays. Three virus isolates were obtained from 34,567 field-collected Ae. albopictus, and all were identified as Cache Valley virus by molecular methods. Ae. albopictus (N = 3,138), collected in Mercer County from late July through early September 2011, also were retested for West Nile virus (WNV) by reverse transcription-polymerase chain reaction, and all were negative. These results corroborate previous findings showing that Ae. albopictus may occasionally acquire Cache Valley virus, a deer-associated arbovirus, in nature. In contrast, we did not detect WNV infection in Ae. albopictus despite concurrent WNV amplification in this region.
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Affiliation(s)
- Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, Department of Environmental Sciences, the Connecticut Agricultural Experiment Station, New Haven, USA
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Molaei G, Andreadis TG, Armstrong PM, Thomas MC, Deschamps T, Cuebas-Incle E, Montgomery W, Osborne M, Smole S, Matton P, Andrews W, Best C, Cornine F, Bidlack E, Texeira T. Vector-host interactions and epizootiology of eastern equine encephalitis virus in Massachusetts. Vector Borne Zoonotic Dis 2013; 13:312-23. [PMID: 23473221 DOI: 10.1089/vbz.2012.1099] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022] Open
Abstract
Eastern equine encephalitis (EEE) virus is a highly pathogenic mosquito-borne zoonosis that is responsible for outbreaks of severe disease in humans and equines, resulting in high mortality or severe neurological impairment in most survivors. In the northeastern United States, EEE virus is maintained in an enzootic cycle involving the ornithophilic mosquito, Culiseta melanura (Coquillett) and passerine birds in freshwater swamp habitats. To evaluate the role of Cs. melanura and Culiseta morsitans (Theobald) in recent episodes of EEE virus activity in Massachusetts, we collected blood-fed mosquitoes between June, 2007, and October, 2008, from virus foci in 6 counties, and identified the source of blood meals by PCR amplification of mitochondrial cytochrome b gene and sequencing. Analysis of 529 Cs. melanura and 25 Cs. morsitans revealed that nearly 99% and 96% of mosquitoes, respectively, acquired blood meals solely from avian hosts. American Robin, Turdus migratorius Linnaeus was identified as the most common vertebrate host for Cs. melanura (21.7%, n=115), followed by Tufted Titmouse, Baeolophus bicolor (L.) (8.7%, n=46), Black-capped Chickadee, Poecile atricapillus (L.) (8.5%, n=45), Scarlet Tanager, Piranga olivacea (Gmelin) (6.8%, n=36), Field Sparrow, Spizella pusilla (Wilson) (6.2%, n=33), Northern Cardinal, Cardinalis cardinalis (L.) (5.7%, n=30), and other mostly Passeriformes birds. Mammalian-derived blood meals were identified as white-tailed deer, Odocoileus virginianus Zimmermann, domestic cow, Bos taurus L., and human, Homo sapiens L. There were 4 isolations of EEE virus, West Nile virus, and Highland J virus from Cs. melanura. Our results in conjunction with other lines of evidence, including reservoir competency, prevalence of antibody, and infection in nature, suggest that the American Robin, Tufted Titmouse, Black-capped Chickadee, and a few other passerine birds may play key roles in supporting EEE virus transmission in Massachusetts. Infrequent blood feeding of Cs. melanura on mammalian hosts, including humans, also indicates that this mosquito may occasionally contribute to epidemic/epizootic transmission of EEE virus in this region.
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Affiliation(s)
- Goudarz Molaei
- Center for Vector Biology & Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06504, USA.
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Anderson JF, Armstrong PM. Prevalence and genetic characterization of Powassan virus strains infecting Ixodes scapularis in Connecticut. Am J Trop Med Hyg 2012; 87:754-9. [PMID: 22890037 DOI: 10.4269/ajtmh.2012.12-0294] [Citation(s) in RCA: 52] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022] Open
Abstract
A total of 30 Powassan virus (POWV) isolates from Ixodes scapularis collected from Bridgeport and North Branford, CT in 2008, 2010, 2011, and 2012 and one earlier isolate from Ixodes cookei collected in Old Lyme, CT in 1978 were characterized by phylogenetic analysis of their envelope gene sequences. Powassan virus sequences segregated into two major groups termed the deer tick virus (DTV) and Powassan (POW) lineages. The lineage from I. cookei was POW. The remaining viruses from I. scapularis grouped with the DTV lineage. Powassan viruses from Bridgeport were nearly identical and clustered with a virus strain from a human in New York. Viruses from North Branford were homogeneous and grouped with viruses from Massachusetts, northwestern Connecticut, and Ontario. These findings suggest that POWV was independently introduced into these geographical locations in Connecticut and maintained focally in their respective environments. An improved method of isolation of POWV in vitro is described.
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Affiliation(s)
- John F Anderson
- Department of Entomology and Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06504-1106, USA.
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Armstrong PM, Prince N, Andreadis TG. Development of a multi-target TaqMan assay to detect eastern equine encephalitis virus variants in mosquitoes. Vector Borne Zoonotic Dis 2012; 12:872-6. [PMID: 22835151 DOI: 10.1089/vbz.2012.1008] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023] Open
Abstract
Disease outbreaks caused by eastern equine encephalitis virus (EEEV; Togaviridae, Alphavirus) may be prevented by implementing effective surveillance and intervention strategies directed against the mosquito vector. Methods for EEEV detection in mosquitoes include a real-time reverse transcriptase PCR technique (TaqMan assay), but we report its failure to detect variants isolated in Connecticut in 2011, due to a single base-pair mismatch in the probe-binding site. To improve the molecular detection of EEEV, we developed a multi-target TaqMan assay by adding a second primer/probe set to provide redundant targets for EEEV detection. The multi-target TaqMan assay had similar performance characteristics to the conventional assay, but also detected newly-evolving strains of EEEV. The approach described here increases the reliability of the TaqMan assay by creating back-up targets for virus detection without sacrificing sensitivity or specificity.
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Affiliation(s)
- Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, Connecticut 06504, USA.
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Armstrong PM, Vossbrinck CR, Andreadis TG, Anderson JF, Pesko KN, Newman RM, Lennon NJ, Birren BW, Ebel GD, Henn MR. Molecular evolution of West Nile virus in a northern temperate region: Connecticut, USA 1999-2008. Virology 2011; 417:203-10. [PMID: 21723580 DOI: 10.1016/j.virol.2011.06.006] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2011] [Revised: 06/07/2011] [Accepted: 06/08/2011] [Indexed: 10/18/2022]
Abstract
West Nile virus (WNV) has become firmly established in northeastern US, reemerging every summer since its introduction into North America in 1999. To determine whether WNV overwinters locally or is reseeded annually, we examined the patterns of viral lineage persistence and replacement in Connecticut over 10 consecutive transmission seasons by phylogenetic analysis. In addition, we compared the full protein coding sequence among WNV isolates to search for evidence of convergent and adaptive evolution. Viruses sampled from Connecticut segregated into a number of well-supported subclades by year of isolation with few clades persisting ≥2 years. Similar viral strains were dispersed in different locations across the state and divergent strains appeared within a single location during a single transmission season, implying widespread movement and rapid colonization of virus. Numerous amino acid substitutions arose in the population but only one change, V→A at position 159 of the envelope protein, became permanently fixed. Several instances of parallel evolution were identified in independent lineages, including one amino acid change in the NS4A protein that appears to be positively selected. Our results suggest that annual reemergence of WNV is driven by both reintroduction and local-overwintering of virus. Despite ongoing evolution of WNV, most amino acid variants occurred at low frequencies and were transient in the virus population.
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Affiliation(s)
- Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, The Connecticut Agricultural Experiment Station, New Haven, CT 06504, USA.
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Armstrong PM, Andreadis TG, Finan SL, Shepard JJ, Thomas MC. Detection of infectious virus from field-collected mosquitoes by vero cell culture assay. J Vis Exp 2011:2889. [PMID: 21694689 DOI: 10.3791/2889] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022] Open
Abstract
Mosquitoes transmit a number of distinct viruses including important human pathogens such as West Nile virus, dengue virus, and chickungunya virus. Many of these viruses have intensified in their endemic ranges and expanded to new territories, necessitating effective surveillance and control programs to respond to these threats. One strategy to monitor virus activity involves collecting large numbers of mosquitoes from endemic sites and testing them for viral infection. In this article, we describe how to handle, process, and screen field-collected mosquitoes for infectious virus by Vero cell culture assay. Mosquitoes are sorted by trap location and species, and grouped into pools containing ≤50 individuals. Pooled specimens are homogenized in buffered saline using a mixer-mill and the aqueous phase is inoculated onto confluent Vero cell cultures (Clone E6). Cell cultures are monitored for cytopathic effect from days 3-7 post-inoculation and any viruses grown in cell culture are identified by the appropriate diagnostic assays. By utilizing this approach, we have isolated 9 different viruses from mosquitoes collected in Connecticut, USA, and among these, 5 are known to cause human disease. Three of these viruses (West Nile virus, Potosi virus, and La Crosse virus) represent new records for North America or the New England region since 1999. The ability to detect a wide diversity of viruses is critical to monitoring both established and newly emerging viruses in the mosquito population.
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Affiliation(s)
- Philip M Armstrong
- Center for Vector Biology and Zoonotic Diseases, Department of Environmental Sciences, The Connecticut Agricultural Experiment Station, USA.
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