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Barzon L. Ongoing and emerging arbovirus threats in Europe. J Clin Virol 2018; 107:38-47. [PMID: 30176404 DOI: 10.1016/j.jcv.2018.08.007] [Citation(s) in RCA: 72] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2018] [Accepted: 08/20/2018] [Indexed: 11/17/2022]
Abstract
During the last decades, arboviruses that are endemic in Europe have expanded their geographic range and caused an increasing number of human outbreaks. These viruses include West Nile virus, which is expanding its area of circulation in central and southern Europe; Usutu virus, with increasing evidence of a role in human disease; tick-borne encephalitis virus, which is being detected in northern areas and at higher altitudes as a consequence of climate warming; Crimean-Congo hemorrhagic fever virus, which is endemic in Eastern Europe and the Middle East, but has been recently detected in Spain; other viruses, such as California encephalitis virus antigenic group, which circulate in northern and central Europe but whose relevance for human disease in largely unknown. In addition, the rise in global travel and trade has posed Europe to an increased risk of introduction and expansion of exotic arthropod vectors and autochthonous transmission of arboviruses, like dengue and chikungunya viruses, following new introductions from endemic areas. Implementation of integrated arbovirus surveillance programs has been crucial to adopt proper control measures. The identification of emerging outbreaks is however challenging and requires a high degree of awareness and laboratory capacity, especially for the most neglected but potentially threatening pathogens.
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Affiliation(s)
- Luisa Barzon
- Department of Molecular Medicine, University of Padova, via A. Gabelli 63, 35121, Padova, Italy.
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Sule WF, Oluwayelu DO, Hernández-Triana LM, Fooks AR, Venter M, Johnson N. Epidemiology and ecology of West Nile virus in sub-Saharan Africa. Parasit Vectors 2018; 11:414. [PMID: 30005653 PMCID: PMC6043977 DOI: 10.1186/s13071-018-2998-y] [Citation(s) in RCA: 43] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2018] [Accepted: 07/06/2018] [Indexed: 12/11/2022] Open
Abstract
West Nile virus (WNV) is the aetiological agent of the mosquito-borne zoonotic disease West Nile fever. The virus, first isolated in Uganda in 1937, evolved into two distinct lineages in sub-Saharan Africa (SSA) that subsequently spread to most continents where the virus has evolved further as evident through phylogenetic analysis of extant genomes. Numerous published reports from the past 70 years from countries in SSA indicate that the virus is endemic across the region. However, due in part to the limited availability of diagnostic methods across large areas of the continent, the human burden of WNV is poorly understood. So too are the drivers for translocation of the virus from countries south of the Sahara Desert to North Africa and Europe. Migratory birds are implicated in this translocation although the transient viraemia, measured in days, and the time taken to migrate, measured in weeks, suggest a more complex mechanism is in play. This review considers the evidence for the presence of WNV across SSA and the role of migratory birds in the emergence of the virus in other continents.
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Affiliation(s)
- Waidi F Sule
- Department of Microbiology, Faculty of Basic and Applied Sciences, Osun State University, Osogbo, Osun State, Nigeria
| | - Daniel O Oluwayelu
- Department of Veterinary Microbiology, University of Ibadan, Ibadan, Oyo State, Nigeria.,Centre for Control and Prevention of Zoonoses, University of Ibadan, Ibadan, Oyo State, Nigeria
| | | | - Anthony R Fooks
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT153NB, UK.,Department of Clinical Infection, Microbiology and Immunology, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - Marietjie Venter
- Emerging Arbo and Respiratory Program, Centre for Viral Zoonosis, Department of Medical Virology, University of Pretoria, Pretoria, South Africa
| | - Nicholas Johnson
- Animal and Plant Health Agency, Woodham Lane, Addlestone, Surrey, KT153NB, UK. .,Faculty of Health and Medicine, University of Surrey, Guildford, Surrey, GU27XH, UK.
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Abstract
Equine populations worldwide are at increasing risk of infection by viruses transmitted by biting arthropods, including mosquitoes, biting midges (Culicoides), sandflies and ticks. These include the flaviviruses (Japanese encephalitis, West Nile and Murray Valley encephalitis), alphaviruses (eastern, western and Venezuelan encephalitis) and the orbiviruses (African horse sickness and equine encephalosis). This review provides an overview of the challenges faced in the surveillance, prevention and control of the major equine arboviruses, particularly in the context of these viruses emerging in new regions of the world.
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Affiliation(s)
- G E Chapman
- Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - M Baylis
- Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - D Archer
- Epidemiology and Population Health, Institute of Infection and Global Health, University of Liverpool, Liverpool, UK
| | - J M Daly
- School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Leicestershire, UK
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Csank T, Drzewnioková P, Korytár Ľ, Major P, Gyuranecz M, Pistl J, Bakonyi T. A Serosurvey of Flavivirus Infection in Horses and Birds in Slovakia. Vector Borne Zoonotic Dis 2018; 18:206-213. [PMID: 29437548 DOI: 10.1089/vbz.2017.2216] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
In central Europe, at least three flaviviruses circulate among vectors and vertebrate hosts. West Nile virus (WNV) and Usutu virus (USUV) are mosquito-borne viruses maintained in the nature by enzootic cycle between mosquitoes and birds. Tick-borne encephalitis virus (TBEV) is a flavivirus causing annual human cases in Slovakia. The aim of this study is the prevalence assessment of flavivirus infections in horses (n = 145) and birds (n = 109) by enzyme-linked immunosorbent assay (ELISA) and confirmation by neutralization test (VNT). WNV antibodies have been detected in 11.7% of tested horses and 11.9% of tested birds and confirmed in 6.9% of horse and 9.2% of bird samples. None of the WNV seropositive or dubious horses had WNV IgM (ELISA), and none of the tested horses had USUV neutralizing antibodies. Autochthonous WNV infections have been confirmed in 16.7% of horses without international travelling history. Most of them were from western Slovakia with known endemic WNV transmission. An autochthonous WNV infection in a horse from highland area of Kremnické vrchy (central Slovakia) with unknown data of WNV circulation and without travelling history was detected. TBEV antibody was detected in 6.2% of horses and in 3.4% has been confirmed. In two horses, WNV and TBEV infection could not be distinguished. Confirmed WNV seropositive were eight raptors showing nonspecific signs or suffering from trauma, one white stork, and one house sparrow. The sparrow was caught in a locality in eastern Slovakia, where WNV RNA had been previously detected in sparrows. USUV neutralizing antibodies were present in pooled sample from four Eurasian great tits. Because of insufficient volume, TBEV VNT was not carried out in birds. Results further prove the endemicity of WNV and other vector-borne flaviviruses in natural and accidental hosts in Slovakia, giving better insight in flavivirus epidemiology in European countries in general.
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Affiliation(s)
- Tomáš Csank
- 1 Department of Microbiology and Immunology, University of Veterinary Medicine and Pharmacy (UVMP) in Košice , Košice, Slovakia
| | - Petra Drzewnioková
- 1 Department of Microbiology and Immunology, University of Veterinary Medicine and Pharmacy (UVMP) in Košice , Košice, Slovakia
| | - Ľuboš Korytár
- 2 Department of Environment, Veterinary Legislation and Economy, University of Veterinary Medicine and Pharmacy (UVMP) in Košice , Košice, Slovakia
| | - Peter Major
- 3 Department of Clinic for Birds and Exotic Animals, University of Veterinary Medicine and Pharmacy (UVMP) in Košice , Košice, Slovakia
| | - Miklós Gyuranecz
- 4 Institute for Veterinary Medical Research, MTA Centre for Agricultural Research , Hungarian Academy of Sciences, Budapest, Hungary
| | - Juraj Pistl
- 1 Department of Microbiology and Immunology, University of Veterinary Medicine and Pharmacy (UVMP) in Košice , Košice, Slovakia
| | - Tamás Bakonyi
- 5 Department of Microbiology and Infectious Diseases, University of Veterinary Medicine , Budapest, Hungary .,6 Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine , Vienna, Vienna, Austria
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56
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Mosquito community influences West Nile virus seroprevalence in wild birds: implications for the risk of spillover into human populations. Sci Rep 2018; 8:2599. [PMID: 29422507 PMCID: PMC5805708 DOI: 10.1038/s41598-018-20825-z] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2017] [Accepted: 01/25/2018] [Indexed: 11/09/2022] Open
Abstract
Mosquito community composition plays a central role in the transmission of zoonotic vector-borne pathogens. We evaluated how the mosquito community affects the seroprevalence of West Nile virus (WNV) in house sparrows along an urbanisation gradient in an area with the endemic circulation of this virus. We sampled 2544 birds and 340829 mosquitoes in 45 localities, analysed in 15 groups, each containing one urban, one rural and one natural area. WNV seroprevalence was evaluated using an epitope-blocking ELISA kit and a micro virus-neutralization test (VNT). The presence of WNV antibodies was confirmed in 1.96% and 0.67% of birds by ELISA and VNT, respectively. The VNT-seropositive birds were captured in rural and natural areas, but not in urban areas. Human population density was zero in all the localities where VNT-positive birds were captured, which potentially explains the low incidence of human WNV cases in the area. The prevalence of neutralizing antibodies against WNV was positively correlated with the abundance of the ornithophilic Culex perexiguus but negatively associated with the abundance of the mammophilic Ochlerotatus caspius and Anopheles atroparvus. These results suggest that the enzootic circulation of WNV in Spain occurs in areas with larger populations of Cx. perexiguus and low human population densities.
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Tmimi FZ, Faraj C, Bkhache M, Mounaji K, Failloux AB, Sarih M. Insecticide resistance and target site mutations (G119S ace-1 and L1014F kdr) of Culex pipiens in Morocco. Parasit Vectors 2018; 11:51. [PMID: 29357900 PMCID: PMC5778619 DOI: 10.1186/s13071-018-2625-y] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 01/08/2018] [Indexed: 12/30/2022] Open
Abstract
Background Control of the mosquito vector Culex pipiens with insecticides is the main way to control arboviruses that the species can transmit such as West Nile virus (WNV) and Rift Valley fever virus (RVFV). However, its efficiency has been hampered by the emergence of insecticide resistance. Little is known about the insecticide-resistance status and underlying resistance mechanisms of field-collected populations of Cx. pipiens in Morocco. Methods Mosquito adults from Mohammadia city in Morocco were reared from immature stages. The level of their susceptibility to insecticides was assessed using standard WHO bioassay. The two forms of the Cx. pipiens complex and their hybrids were identified by a multiplex PCR. Identified mosquitoes were then tested for the presence of the G119S ace-1 and L1014F kdr mutations using PCR-RFLP and PCR assays, respectively. Results WHO bioassays indicated that Cx. pipiens was resistant to all tested insecticides: lambda-cyhalothrin (49% mortality), permethrin (63% mortality), DDT (16% mortality), malation (52% mortality) and bendiocarb (39% mortality). The frequency of the 119S allele was almost identical in the pipiens form and hybrids (0.11 and 0.15, respectively) whereas it remained low in the molestus form (0.03). No significant correlation was observed between the G119S allele and the resistance phenotype to two tested insecticides (malathion and bendiocarb). The frequency of the L1014F allele was identical in the pipiens form and hybrids (0.44) whereas it was low in the molestus form (0.36) but no significant difference was detected (χ2 = 1.46, df = 1, P = 0.225). The presence of the L1014F kdr mutation was significantly associated with resistance to three tested insecticides in pipiens form (P = 0.0019, P = 0.0023 and P = 0.023, respectively, to lambda-cyhalothrin, permethrin and DDT) whereas no significant correlation was observed between the L1014F kdr mutation and resistance phenotype in molestus form and hybrids to the three tested insecticides. Conclusion These findings showed that wild populations of Cx. pipiens have developed resistance against the main insecticide families with different modes of action: organochlorines (DDT), organophosphates (malathion), carbamates (bendiocarb), pyrethroids (lambda-cyhalothrin, permethrin). Therefore, urgent action should be taken to manage the resistance in this species to maintain the effectiveness of arbovirus control.
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Affiliation(s)
- Fatim-Zohra Tmimi
- Institut Pasteur du Maroc, Service de Parasitologie et des Maladies Vectorielles, Place Louis Pasteur, 20360, Casablanca, Morocco.,Faculté des Sciences Ain-Chock, Laboratoire de Physiopathologie, Génétique Moléculaire et Biotechnologie, Casablanca, Morocco
| | - Chafika Faraj
- Institut National d'Hygiène, Laboratoire d'Entomologie Médicale, Rabat, Morocco
| | - Meriem Bkhache
- Institut Pasteur du Maroc, Service de Parasitologie et des Maladies Vectorielles, Place Louis Pasteur, 20360, Casablanca, Morocco
| | - Khadija Mounaji
- Faculté des Sciences Ain-Chock, Laboratoire de Physiopathologie, Génétique Moléculaire et Biotechnologie, Casablanca, Morocco
| | - Anna-Bella Failloux
- Institut Pasteur, Department of Virology, Arboviruses and Insect Vectors, 25-28 rue du Docteur Roux, 75724, Paris, France
| | - M'hammed Sarih
- Institut Pasteur du Maroc, Service de Parasitologie et des Maladies Vectorielles, Place Louis Pasteur, 20360, Casablanca, Morocco.
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Carrasco-Hernandez R, Jácome R, López Vidal Y, Ponce de León S. Are RNA Viruses Candidate Agents for the Next Global Pandemic? A Review. ILAR J 2017; 58:343-358. [PMID: 28985316 PMCID: PMC7108571 DOI: 10.1093/ilar/ilx026] [Citation(s) in RCA: 124] [Impact Index Per Article: 17.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2017] [Revised: 07/14/2017] [Accepted: 07/15/2017] [Indexed: 12/16/2022] Open
Abstract
Pathogenic RNA viruses are potentially the most important group involved in zoonotic disease transmission, and they represent a challenge for global disease control. Their biological diversity and rapid adaptive rates have proved to be difficult to overcome and to anticipate by modern medical technology. Also, the anthropogenic change of natural ecosystems and the continuous population growth are driving increased rates of interspecies contacts and the interchange of pathogens that can develop into global pandemics. The combination of molecular, epidemiological, and ecological knowledge of RNA viruses is therefore essential towards the proper control of these emergent pathogens. This review outlines, throughout different levels of complexity, the problems posed by RNA viral diseases, covering some of the molecular mechanisms allowing them to adapt to new host species-and to novel pharmaceutical developments-up to the known ecological processes involved in zoonotic transmission.
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Affiliation(s)
- R Carrasco-Hernandez
- R. Carrasco-Hernandez, PhD, is a postdoctoral research fellow at the Microbiome Laboratory in the Postgraduate Division of the Faculty of Medicine at the Universidad Nacional Autónoma de México, CDMX
| | - Rodrigo Jácome
- Rodrigo Jácome, MD, PhD, is a postdoctoral research fellow at the Microbiome Laboratory in the Postgraduate Division of the Faculty of Medicine at the Universidad Nacional Autónoma de México, CDMX
| | - Yolanda López Vidal
- Yolanda López-Vidal, MD, PhD, is an associate professor “C” and is responsible for the Program of Microbial Molecular Immunology in the Department of Microbiology and Parasitology of the Faculty of Medicine at the Universidad Nacional Autónoma de México, CDMX
| | - Samuel Ponce de León
- Samuel Ponce-de-León, MD, MSc, is an associate professor “C”, is responsible for the Microbiome Laboratory and Coordinator of the University Program for Health Research of the Faculty of Medicine at the Universidad Nacional Autónoma de México, CDMX
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59
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Nikookar SH, Fazeli-Dinan M, Azari-Hamidian S, Mousavinasab SN, Arabi M, Ziapour SP, Shojaee J, Enayati A. Species composition and abundance of mosquito larvae in relation with their habitat characteristics in Mazandaran Province, northern Iran. BULLETIN OF ENTOMOLOGICAL RESEARCH 2017; 107:598-610. [PMID: 28956526 DOI: 10.1017/s0007485317000074] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
Mosquitoes transmit a variety of diseases to humans. Their abundance and distribution are related to the characteristics of larval habitats. Mosquito larvae were collected from 120 natural and artificial habitats in 30 villages of 16 counties using standard 350 ml dippers and pipette, on a monthly basis from May-December 2014 in Mazandaran Province, northern Iran. Larval habitat characteristics were recorded separately, based on the conditions of the habitats (permanent or temporary, stagnant or running), type of habitats (natural or artificial), vegetation, exposure to sun, type of bed, water condition (clear or turbid), expanse (m), depth (cm, m) and temperature (°C) of habitats. The relationship between larval density and environmental variables was assessed by Chi-square tests. Totally, 19,840 larvae from three genera and 16 species were collected and identified. Anopheles maculipennis s.l. and Culex pipiens were the dominant species and collected with the highest density in plain areas. The highest number of larvae were collected from natural habitats (60.34%), including; river edge, marsh, pit and wetlands; with temporary and stagnant water, expanse of 0-5 m, depth of 1-25 cm, without plant, shadow-sun, muddy floor, turbid water, temperature 20-25°C and in sunny conditions. River edge and rice fields for An. maculipennis s.l and, wetlands and discarded tires for Cx. pipiens were the main larval habitats in the province. Statistical analysis revealed significant relation between occurrence of An. maculipennis s.l., Cx. pipiens, Culex torrentium, Culex mimeticus and Cs. annulata with each of the environmental variables (P < 0.001). These findings are essential in expanding our knowledge of the vectors ecology specially the type of habitat preference and will be beneficial in larval control programs.
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Affiliation(s)
- S H Nikookar
- Student Research Committee,Department of Medical Entomology and Vector Control,Health Sciences Research Center,School of Public Health, Mazandaran University of Medical Sciences,Sari,Iran
| | - M Fazeli-Dinan
- Department of Medical Entomology and Vector Control,School of Public Health and Health Sciences Research Center,Mazandaran University of Medical Science,Sari,Iran
| | - S Azari-Hamidian
- School of Health, Research Center of Health and Environment, Guilan University of Medical Sciences,Rasht,Iran
| | - S N Mousavinasab
- Department of Biostatistics,Mazandaran University of Medical Sciences,Sari,Iran
| | - M Arabi
- Department of Epidemiology, Faculty of Medicine,Mazandaran University of Medical Sciences,Sari,Iran
| | - S P Ziapour
- Student Research Committee,Department of Medical Entomology and Vector Control,Health Sciences Research Center,School of Public Health, Mazandaran University of Medical Sciences,Sari,Iran
| | - J Shojaee
- Health Sciences Research Center,Students Research Committee,Mazandaran University of Medical Sciences,Sari,Iran
| | - A Enayati
- Head of Medical Entomology Department,School of Public Health and Health Sciences Research Center,Mazandaran University of Medical Sciences,Sari,Iran
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60
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Soltész Z, Erdélyi K, Bakonyi T, Barna M, Szentpáli-Gavallér K, Solt S, Horváth É, Palatitz P, Kotymán L, Dán Á, Papp L, Harnos A, Fehérvári P. West Nile virus host-vector-pathogen interactions in a colonial raptor. Parasit Vectors 2017; 10:449. [PMID: 28962629 PMCID: PMC5622512 DOI: 10.1186/s13071-017-2394-z] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/08/2017] [Accepted: 09/19/2017] [Indexed: 11/12/2022] Open
Abstract
Background Avian host species have different roles in the amplification and maintenance of West Nile virus (WNV), therefore identifying key taxa is vital in understanding WNV epidemics. Here, we present a comprehensive case study conducted on red-footed falcons, where host-vector, vector-virus and host-virus interactions were simultaneously studied to evaluate host species contribution to WNV circulation qualitatively. Results Mosquitoes were trapped inside red-footed falcon nest-boxes by a method originally developed for the capture of blackflies and midges. We showed that this approach is also efficient for trapping mosquitoes and that the number of trapped vectors is a function of host attraction. Brood size and nestling age had a positive effect on the number of attracted Culex pipiens individuals while the blood-feeding success rate of both dominant Culex species (Culex pipiens and Culex modestus) markedly decreased after the nestlings reached 14 days of age. Using RT-PCR, we showed that WNV was present in these mosquitoes with 4.2% (CI: 0.9–7.5%) prevalence. We did not detect WNV in any of the nestling blood samples. However, a relatively high seroprevalence (25.4% CI: 18.8–33.2%) was detected with an enzyme-linked immunoabsorbent assay (ELISA). Using the ELISA OD ratios as a proxy to antibody titers, we showed that older seropositive nestlings have lower antibody levels than their younger conspecifics and that hatching order negatively influences antibody levels in broods with seropositive nestlings. Conclusions Red-footed falcons in the studied system are exposed to a local sylvatic WNV circulation, and the risk of infection is higher for younger nestlings. However, the lack of individuals with viremia and the high WNV seroprevalence, indicate that either host has a very short viremic period or that a large percentage of nestlings in the population receive maternal antibodies. This latter assumption is supported by the age and hatching order dependence of antibody levels found for seropositive nestlings. Considering the temporal pattern in mosquito feeding success, maternal immunity may be effective in protecting progeny against WNV infection despite the short antibody half-life measured in various other species. We conclude that red-footed falcons seem to have low WNV host competence and are unlikely to be effective virus reservoirs in the studied region.
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Affiliation(s)
- Zoltán Soltész
- Lendület Ecosystem Services Research Group, MTA Centre for Ecological Research, Vácrátót, Hungary. .,Hungarian Natural History Museum, Budapest, Hungary.
| | - Károly Erdélyi
- National Food Chain Safety Office, Veterinary Diagnostic Directorate, Budapest, Hungary
| | - Tamás Bakonyi
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary.,Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine, Vienna, Austria
| | - Mónika Barna
- Department of Microbiology and Infectious Diseases, University of Veterinary Medicine, Budapest, Hungary
| | | | - Szabolcs Solt
- MME/BirdLife Hungary, Red-footed Falcon Conservation Working Group, Budapest, Hungary
| | - Éva Horváth
- MME/BirdLife Hungary, Red-footed Falcon Conservation Working Group, Budapest, Hungary
| | - Péter Palatitz
- MME/BirdLife Hungary, Red-footed Falcon Conservation Working Group, Budapest, Hungary
| | | | - Ádám Dán
- National Food Chain Safety Office, Veterinary Diagnostic Directorate, Budapest, Hungary
| | - László Papp
- Hungarian Academy of Sciences, Biological Section, Budapest, Hungary
| | - Andrea Harnos
- Department of Biomathematics and Informatics, University of Veterinary Medicine, Budapest, Hungary
| | - Péter Fehérvári
- Hungarian Natural History Museum, Budapest, Hungary.,Department of Biomathematics and Informatics, University of Veterinary Medicine, Budapest, Hungary
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Abstract
Abstract
The tick-borne encephalitis virus (TBEV) and West Nile virus (WNV) are arboviruses of the genus Flavivirus in the family Flaviviridae. Their hosts are vertebratesof which rodents are the reservoirs of TBEV and birds are the reservoirs of WNV. Both viruses are transmitted from reservoirs to mammals by vectors. TBEV is transmitted by ticks (mostly Ixodes spp.) and WNV by mosquitoes (mostly Culex spp.). Both viruses are capable of infecting mammals, including man. TBEV and WNV are neurotropic, however infection is, in most cases, subclinical or accompanied by only moderate general signs. However, in some cases they can cause serious disturbances of the CNS. Our study focused on the detection of the genomes of TBEV and WNV in vectors by means of the reverse-transcription polymerase chain reaction (RT-PCR). The flavivirus genome was detected by means of oligonucleotides delineating the sequence in NS5 gene that encodes viral RNA-dependent RNA-polymerase. For the detection of TBEV, we used the oligonucleotide pair detecting the structural envelope protein. The positive samples were subjected to the sequence and phylogenetic analysis. The WNV was not detected in any of the pooled samples prepared from 616 mosquitoes captured in the vicinity of the village Drienovec, district Košice-surroundings. The investigation of 676 ticks demonstrated the presence of one strain of TBEV. One blood-fed I. ricinus female was obtained from a goat grazing in a pasture in the Dúbrava area close to Prešov. The genetic analysis revealed the presence of a strain close to the endemic strainsof TBEV Hypr and Neudörfl. The results of our study can become a motivation for additional studies in model locations oriented on ecology and circulation of these important zoonotic flaviviruses.
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62
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Al-Jabi SW. Global research trends in West Nile virus from 1943 to 2016: a bibliometric analysis. Global Health 2017; 13:55. [PMID: 28774315 PMCID: PMC5543434 DOI: 10.1186/s12992-017-0284-y] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2016] [Accepted: 07/28/2017] [Indexed: 12/14/2022] Open
Abstract
BACKGROUND West Nile virus (WNV) is an emerging infectious disease which is most commonly transmitted to humans through mosquito, and is considered a major public-health problem worldwide. The aim of the current study is to bibliometrically analyze the quantity and quality of publications indexed in Scopus from different countries to reveal the characteristics of global research output regarding WNV. METHODS This study is a bibliometric analysis based on the Scopus database. This study focused on identifying WNV publication trends with regard to publication year, publication type, prolific countries, language of publication, as well as, prolific journals, citations, and collaboration patterns. RESULTS A total of 4729 publications were considered in this study, which were published between 1943 and 2016. The annual quantity of literature published before 2000 followed a low rate of research growth; while the quantity of publications after 2000 were published in a stage of rapid development. The country with the greatest number of publications in WNV research field was the USA with 2304 (48.7%) publications, followed by France with 224 (4.7%) publications, and Canada with 222 (4.7%) publications. Contributions from low- and middle-income countries (LMIC) were considerably small, that is, (n = 519 publications; 11%). All publications related to WNV achieved h-index of 140 and were cited 124,222 times. The median [interquartile range] number of citations per article thus amounts to 9 [2-28]. The USA had the highest h-index of 131. Emerging Infectious Diseases is the most productive journal with 227 articles, followed by Journal of Virology with 162 publications. The result designated that Centers for Disease Control and Prevention was ranked the first in terms of publication output, followed by National Center for Emerging and Zoonotic Infectious Diseases. CONCLUSIONS There is an obvious trend of WNV research after 2000, and countries with high income have more contributions in WNV research field. The research output is low among LMIC. The USA produced the largest number of publications. The Centers for Disease Control and Prevention obtained the leading position of the institutions in terms of publication output. In general, this study not only presents a full view of global WNV research, but also can contribute for future further research in this field.
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Affiliation(s)
- Samah W Al-Jabi
- Department of Clinical and Community Pharmacy, Faculty of Medicine and Health Sciences, An-Najah National University, Nablus, 44839, Palestine.
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63
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Modelling West Nile virus transmission risk in Europe: effect of temperature and mosquito biotypes on the basic reproduction number. Sci Rep 2017; 7:5022. [PMID: 28694450 PMCID: PMC5504010 DOI: 10.1038/s41598-017-05185-4] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2017] [Accepted: 05/25/2017] [Indexed: 12/31/2022] Open
Abstract
West Nile virus (WNV) is a mosquito-borne flavivirus which has caused repeated outbreaks in humans in southern and central Europe, but thus far not in northern Europe. The main mosquito vector for WNV, Culex pipiens, consists of two behaviourally distinct biotypes, pipiens and molestus, which can form hybrids. Differences between biotypes, such as vector competence and host preference, could be important in determining the risk of WNV outbreaks. Risks for WNV establishment can be modelled with basic reproduction number (R0) models. However, existing R0 models have not differentiated between biotypes. The aim of this study was, therefore, to explore the role of temperature-dependent and biotype-specific effects on the risk of WNV establishment in Europe. We developed an R0 model with temperature-dependent and biotype-specific parameters, and calculated R0 values using the next-generation matrix for several scenarios relevant for Europe. In addition, elasticity analysis was done to investigate the contribution of each biotype to R0. Global warming and increased mosquito-to-host ratios can possibly result in more intense WNV circulation in birds and spill-over to humans in northern Europe. Different contributions of the Cx. pipiens biotypes to R0 shows the importance of including biotype-specific parameters in models for reliable WNV risk assessments.
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Abstract
Although long recognized as a human pathogen, West Nile virus (WNV) emerged as a significant public health problem following its introduction and spread across North America. Subsequent years have seen a greater understanding of all aspects of this viral infection. The North American epidemic resulted in a further understanding of the virology, pathogenesis, clinical features, and epidemiology of WNV infection. Approximately 80% of human WNV infections are asymptomatic. Most symptomatic people experience an acute systemic febrile illness; less than 1% of infected people develop neuroinvasive disease, which typically manifests as meningitis, encephalitis, or anterior myelitis resulting in acute flaccid paralysis. Older age is associated with more severe illness and higher mortality; other risk factors for poor outcome have been challenging to identify. In addition to natural infection through mosquito bites, transfusion- and organ transplant-associated infections have occurred. Since there is no definitive treatment for WNV infection, protection from mosquito bites and other preventative measures are critical. WNV has reached an endemic pattern in North America, but the future epidemiologic pattern is uncertain.
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Zehender G, Veo C, Ebranati E, Carta V, Rovida F, Percivalle E, Moreno A, Lelli D, Calzolari M, Lavazza A, Chiapponi C, Baioni L, Capelli G, Ravagnan S, Da Rold G, Lavezzo E, Palù G, Baldanti F, Barzon L, Galli M. Reconstructing the recent West Nile virus lineage 2 epidemic in Europe and Italy using discrete and continuous phylogeography. PLoS One 2017; 12:e0179679. [PMID: 28678837 PMCID: PMC5497961 DOI: 10.1371/journal.pone.0179679] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2017] [Accepted: 06/04/2017] [Indexed: 11/24/2022] Open
Abstract
West Nile virus lineage 2 (WNV-2) was mainly confined to sub-Saharan Africa until the early 2000s, when it was identified for the first time in Central Europe causing outbreaks of human and animal infection. The aim of this study was to reconstruct the origin and dispersion of WNV-2 in Central Europe and Italy on a phylodynamic and phylogeographical basis. To this aim, discrete and continuous space phylogeographical models were applied to a total of 33 newly characterised full-length viral genomes obtained from mosquitoes, birds and humans in Northern Italy in the years 2013–2015 aligned with 64 complete sequences isolated mainly in Europe. The European isolates segregated into two highly significant clades: a small one including three sequences and a large clade including the majority of isolates obtained in Central Europe since 2004. Discrete phylogeographical analysis showed that the most probable location of the root of the largest European clade was in Hungary a mean 12.78 years ago. The European clade bifurcated into two highly supported subclades: one including most of the Central/East European isolates and the other encompassing all of the isolates obtained in Greece. The continuous space phylogeographical analysis of the Italian clade showed that WNV-2 entered Italy in about 2008, probably by crossing the Adriatic sea and reaching a central area of the Po Valley. The epidemic then spread simultaneously eastward, to reach the region of the Po delta in 2013, and westward to the border area between Lombardy and Piedmont in 2014; later, the western strain changed direction southward, and reached the central area of the Po valley once again in 2015. Over a period of about seven years, the virus spread all over an area of northern Italy by following the Po river and its main tributaries.
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Affiliation(s)
- Gianguglielmo Zehender
- Department of Biomedical and Clinical Sciences "L.Sacco", University of Milan, Milano, Italy
- CRC-Coordinated Research Center “EpiSoMI”, University of Milan, Milano, Italy
- * E-mail:
| | - Carla Veo
- Department of Biomedical and Clinical Sciences "L.Sacco", University of Milan, Milano, Italy
- CRC-Coordinated Research Center “EpiSoMI”, University of Milan, Milano, Italy
| | - Erika Ebranati
- Department of Biomedical and Clinical Sciences "L.Sacco", University of Milan, Milano, Italy
- CRC-Coordinated Research Center “EpiSoMI”, University of Milan, Milano, Italy
| | - Valentina Carta
- Department of Biomedical and Clinical Sciences "L.Sacco", University of Milan, Milano, Italy
- CRC-Coordinated Research Center “EpiSoMI”, University of Milan, Milano, Italy
| | - Francesca Rovida
- Molecular Virology Unit, Microbiology and Virology Department, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Elena Percivalle
- Molecular Virology Unit, Microbiology and Virology Department, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Ana Moreno
- Experimental Zooprophylactic Institute of Lombardy and Emilia-Romagna (IZSLER), Brescia, Italy
| | - Davide Lelli
- Experimental Zooprophylactic Institute of Lombardy and Emilia-Romagna (IZSLER), Brescia, Italy
| | - Mattia Calzolari
- Experimental Zooprophylactic Institute of Lombardy and Emilia-Romagna (IZSLER), Reggio Emilia, Italy
| | - Antonio Lavazza
- Experimental Zooprophylactic Institute of Lombardy and Emilia-Romagna (IZSLER), Brescia, Italy
| | - Chiara Chiapponi
- Experimental Zooprophylactic Institute of Lombardy and Emilia-Romagna (IZSLER), Parma, Italy
| | - Laura Baioni
- Experimental Zooprophylactic Institute of Lombardy and Emilia-Romagna (IZSLER), Parma, Italy
| | - Gioia Capelli
- Experimental Zooprophylactic Institute of Venice, Legnaro, Padua, Italy
| | - Silvia Ravagnan
- Experimental Zooprophylactic Institute of Venice, Legnaro, Padua, Italy
| | - Graziana Da Rold
- Experimental Zooprophylactic Institute of Venice, Legnaro, Padua, Italy
| | - Enrico Lavezzo
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Giorgio Palù
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Fausto Baldanti
- Molecular Virology Unit, Microbiology and Virology Department, Fondazione IRCCS Policlinico San Matteo, Pavia, Italy
| | - Luisa Barzon
- Department of Molecular Medicine, University of Padova, Padova, Italy
| | - Massimo Galli
- Department of Biomedical and Clinical Sciences "L.Sacco", University of Milan, Milano, Italy
- CRC-Coordinated Research Center “EpiSoMI”, University of Milan, Milano, Italy
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Sánchez-Gómez A, Amela C, Fernández-Carrión E, Martínez-Avilés M, Sánchez-Vizcaíno JM, Sierra-Moros MJ. Risk mapping of West Nile virus circulation in Spain, 2015. Acta Trop 2017; 169:163-169. [PMID: 28212847 DOI: 10.1016/j.actatropica.2017.02.022] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2016] [Revised: 02/10/2017] [Accepted: 02/13/2017] [Indexed: 01/19/2023]
Abstract
West Nile fever is an emergent disease in Europe. The objective of this study was to conduct a predictive risk mapping of West Nile Virus (WNV) circulation in Spain based on historical data of WNV circulation. Areas of Spain with evidence of WNV circulation were mapped based on data from notifications to the surveillance systems and a literature review. A logistic regression-based spatial model was used to assess the probability of WNV circulation. Data were analyzed at municipality level. Mean temperatures of the period from June to October, presence of wetlands and presence of Special Protection Areas for birds were considered as potential predictors. Two predictors of WNV circulation were identified: higher temperature [adjusted odds ratio (AOR) 2.07, 95% CI 1.82-2.35, p<0.01] and presence of wetlands (3.37, 95% CI 1.89-5.99, p<0.01). Model validations indicated good predictions: area under the ROC curve was 0.895 (95% CI 0.870-0.919) for internal validation and 0.895 (95% CI 0.840-0.951) for external validation. This model could support improvements of WNV risk- based surveillance in Spain. The importance of a comprehensive surveillance for WNF, including human, animal and potential vectors is highlighted, which could additionally result in model refinements.
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Affiliation(s)
- Amaya Sánchez-Gómez
- Coordinating Centre for Health Alerts and Emergencies, General Directorate of Public Health, Quality and Innovation, Ministry of Health, Social Services and Equality, Madrid, Spain Paseo del Prado 18-20, 28071 Madrid, Spain.
| | - Carmen Amela
- Coordinating Centre for Health Alerts and Emergencies, General Directorate of Public Health, Quality and Innovation, Ministry of Health, Social Services and Equality, Madrid, Spain Paseo del Prado 18-20, 28071 Madrid, Spain.
| | - Eduardo Fernández-Carrión
- VISAVET Centre and Animal Health Department, Faculty of Veterinary Sciences, Complutense University, Avenida Puerta de Hierro, s/n, 28040 Madrid, Spain.
| | - Marta Martínez-Avilés
- VISAVET Centre and Animal Health Department, Faculty of Veterinary Sciences, Complutense University, Avenida Puerta de Hierro, s/n, 28040 Madrid, Spain.
| | - José Manuel Sánchez-Vizcaíno
- VISAVET Centre and Animal Health Department, Faculty of Veterinary Sciences, Complutense University, Avenida Puerta de Hierro, s/n, 28040 Madrid, Spain.
| | - María José Sierra-Moros
- Coordinating Centre for Health Alerts and Emergencies, General Directorate of Public Health, Quality and Innovation, Ministry of Health, Social Services and Equality, Madrid, Spain Paseo del Prado 18-20, 28071 Madrid, Spain.
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Surveillance of Arthropod-Borne Viruses and Their Vectors in the Mediterranean and Black Sea Regions Within the MediLabSecure Network. CURRENT TROPICAL MEDICINE REPORTS 2017; 4:27-39. [PMID: 28386524 PMCID: PMC5362652 DOI: 10.1007/s40475-017-0101-y] [Citation(s) in RCA: 38] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023]
Abstract
PURPOSE OF REVIEW Arboviruses, viruses transmitted by arthropods such as mosquitoes, ticks, sandflies, and fleas are a significant threat to public health because of their epidemic and zoonotic potential. The geographical distribution of mosquito-borne diseases such as West Nile (WN), Rift Valley fever (RVF), Dengue, Chikungunya, and Zika has expanded over the last decades. Countries of the Mediterranean and Black Sea regions are not spared. Outbreaks of WN are repeatedly reported in the Mediterranean basin. Human cases of RVF were reported at the southern borders of the Maghreb region. For this reason, establishing the basis for the research to understand the potential for the future emergence of these and other arboviruses and their expansion into new geographic areas became a public health priority. In this context, the European network "MediLabSecure" gathering laboratories in 19 non-EU countries from the Mediterranean and Black Sea regions seeks to improve the surveillance (of animals, humans, and vectors) by reinforcing capacity building and harmonizing national surveillance systems to address this important human and veterinary health issue. The aim of this review is to give an exhaustive overview of arboviruses and their vectors in the region. RECENT FINDINGS The data presented underline the importance of surveillance in the implementation of more adapted control strategies to combat vector-borne diseases. Partner laboratories within the MediLabSecure network present a wide range of infrastructures and have benefited from different training programs. SUMMARY Although reporting of arboviral presence is not carried out in a systematic manner, the expansion of the area where arboviruses are present cannot be disputed. This reinforces the need for increasing surveillance capacity building in this region to prevent future emergences.
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Marini G, Guzzetta G, Baldacchino F, Arnoldi D, Montarsi F, Capelli G, Rizzoli A, Merler S, Rosà R. The effect of interspecific competition on the temporal dynamics of Aedes albopictus and Culex pipiens. Parasit Vectors 2017; 10:102. [PMID: 28228159 PMCID: PMC5322594 DOI: 10.1186/s13071-017-2041-8] [Citation(s) in RCA: 28] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2016] [Accepted: 02/16/2017] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Aedes albopictus and Culex pipiens larvae reared in the same breeding site compete for resources, with an asymmetrical outcome that disadvantages only the latter species. The impact of these interactions on the overall ecology of these two species has not yet been assessed in the natural environment. In the present study, the temporal patterns of adult female mosquitoes from both species were analysed in north-eastern Italy, and substantial temporal shifts between abundance curves of Cx. pipiens and Ae. albopictus were observed in several sites. To understand which factors can drive the observed temporal shifts, we developed a mechanistic model that takes explicitly into account the effect of temperature on the development and survival of all mosquito stages. We also included into the model the effect of asymmetric interspecific competition, by adding a mortality term for Cx. pipiens larvae proportional to the larval abundance of Ae. albopictus within the same breeding site. Model calibration was performed through a Markov Chain Monte Carlo approach using weekly capture data collected in our study sites during 2014 and 2015. RESULTS In almost half of observation sites, temporal shifts were due to competition, with an early decline of Cx. pipiens caused by the concurrent rise in abundance of its competitor, and this effect was enhanced by higher abundance of both species. We estimate that competition may reduce Cx. pipiens abundance in some sites by up to about 70%. However, in some cases temporal shifts can also be explained in the absence of competition between species resulting from a "temporal niche" effect, when the optimal fitness to environmental conditions for the two species are reached at different times of the year. CONCLUSIONS Our findings demonstrate the importance of considering ecological interactions and, in particular, competition between mosquito species in temperate climates, with important implications for risk assessment of mosquito transmitted pathogens, as well as the implementation of effective control measures.
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Affiliation(s)
- Giovanni Marini
- Department of Mathematics, University of Trento, Trento, Italy
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Trento, Italy
| | | | - Frederic Baldacchino
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Trento, Italy
| | - Daniele Arnoldi
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Trento, Italy
| | - Fabrizio Montarsi
- Laboratory of Parasitology, Istituto Zooprofilattico Sperimentale delle Venezie, Padova, Italy
| | - Gioia Capelli
- Laboratory of Parasitology, Istituto Zooprofilattico Sperimentale delle Venezie, Padova, Italy
| | - Annapaola Rizzoli
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Trento, Italy
| | | | - Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all’Adige, Trento, Italy
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Paphitou NI, Tourvas A, Floridou D, Richter J, Tryfonos C, Christodoulou C. The first human case of neuroinvasive West Nile virus infection identified in Cyprus. J Infect Public Health 2017; 10:891-893. [PMID: 28233724 DOI: 10.1016/j.jiph.2017.02.003] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2016] [Revised: 01/23/2017] [Accepted: 02/04/2017] [Indexed: 11/18/2022] Open
Abstract
West Nile virus infection can pose a diagnostic challenge to clinicians, especially in geographic areas where human cases of this disease have never been encountered before. In August 2016, the first human case of West Nile virus infection was diagnosed in Cyprus. An elderly non immunosuppressed patient with a history of recent travel, presented with a clinical picture of rapidly progressing ascending paralysis mimicking Guillain-Barré syndrome. Neuroinvasive West Nile virus disease was diagnosed by detecting West Nile virus nucleic acid in the patient's cerebrospinal fluid. Public health measures were taken raising awareness regarding this disease and its prevention. Clinical vigilance to consider West Nile virus as a possible emerging pathogen in the appropriate clinical setting is warranted and could benefit individual patients.
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Affiliation(s)
- Niki I Paphitou
- Nicosia General Hospital Intensive Care Clinic, Nicosia, Cyprus.
| | | | - Dora Floridou
- Nicosia General Hospital Intensive Care Clinic, Nicosia, Cyprus; Cyprus Institute of Neurology and Genetics, Department of Molecular Virology, 6 International Airport Ave., Agios Dometios, 2379 Nicosia Nicosia, Cyprus.
| | - Jan Richter
- Cyprus Institute of Neurology and Genetics, Department of Molecular Virology, 6 International Airport Ave., Agios Dometios, 2379 Nicosia Nicosia, Cyprus.
| | - Christina Tryfonos
- Cyprus Institute of Neurology and Genetics, Department of Molecular Virology, 6 International Airport Ave., Agios Dometios, 2379 Nicosia Nicosia, Cyprus.
| | - Christina Christodoulou
- Cyprus Institute of Neurology and Genetics, Department of Molecular Virology, 6 International Airport Ave., Agios Dometios, 2379 Nicosia Nicosia, Cyprus.
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Marini G, Rosá R, Pugliese A, Heesterbeek H. Exploring vector-borne infection ecology in multi-host communities: A case study of West Nile virus. J Theor Biol 2016; 415:58-69. [PMID: 27986465 DOI: 10.1016/j.jtbi.2016.12.009] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/26/2016] [Revised: 12/07/2016] [Accepted: 12/10/2016] [Indexed: 10/20/2022]
Abstract
In this study, we develop a model to investigate how ecological factors might affect the dynamics of a vector-borne pathogen in a population composed by different hosts which interact with each other. Specifically, we consider the case when different host species compete with each other, as they share the same habitat, and the vector might have different feeding preference, which can also be time dependent. As a prototypical example, we apply our model to study the invasion and spread, during a typical season, of West Nile virus in an ecosystem composed of two competent avian host species and possibly of dead-end host species. We found that competition and vector feeding preferences can profoundly influence pathogen invasion, influencing its probability to start an epidemic, and influencing transmission rates. Finally, when considering time-dependent feeding preferences, as observed in the field, we noted that the virus circulation could be amplified and that the timing of epidemic peaks could be changed. Our work highlights that ecological interactions between hosts can have a profound influence on the dynamics of the pathogen and that, when modeling vector-borne infections, vector feeding behavior should, for this reason, be carefully evaluated.
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Affiliation(s)
- Giovanni Marini
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all'Adige, TN, Italy; Department of Mathematics, University of Trento, via Sommarive 14, 38123 Povo, Trento, Italy.
| | - Roberto Rosá
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach 1, 38010 San Michele all'Adige, TN, Italy
| | - Andrea Pugliese
- Department of Mathematics, University of Trento, via Sommarive 14, 38123 Povo, Trento, Italy
| | - Hans Heesterbeek
- Faculty of Veterinary Medicine, University of Utrecht, Yalelaan 7, 3584 CL Utrecht, The Netherlands
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Cotar AI, Falcuta E, Prioteasa LF, Dinu S, Ceianu CS, Paz S. Transmission Dynamics of the West Nile Virus in Mosquito Vector Populations under the Influence of Weather Factors in the Danube Delta, Romania. ECOHEALTH 2016; 13:796-807. [PMID: 27709311 DOI: 10.1007/s10393-016-1176-y] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/22/2015] [Revised: 09/01/2016] [Accepted: 09/02/2016] [Indexed: 05/28/2023]
Abstract
Mosquitoes were collected in the Danube Delta during the active seasons of 2011-2013. For Culex spp. mosquitoes, the abundance was calculated. Culex pipiens (sensu lato), (s.l.) and Culex modestus pools were tested for the presence of West Nile virus (WNV) genome, and the maximum likelihood of the infection rate was established. Mean daily temperatures and precipitation were obtained for the closest meteorological station. A negative binominal model was used to evaluate linkages between the temperature/precipitation and mosquito population size. A zero-inflated negative binomial model was used to test the relationship between the temperature and the infection rate. A single complex model for infection rate prediction was also used. The linkages were calculated for lag 0 and for 10 days earlier (lag 1), 20 days earlier (lag 2), and 30 days earlier (lag 3). Significant positive linkages (P < 0.001) were detected between temperature and mosquito population size for lag 1, lag 2, and lag 3. The linkages between temperature and infection rates were positive and significant for lag 2 and lag 3. Negative significant (P < 0.001) results were detected between precipitation and infection rates for lags 1, 2, and 3. The complex model showed that the best predictors for infection rate are the temperature, 20 days earlier (positive linkage) and the precipitation, 30 days earlier (negative linkage). Positive temperature anomalies in spring and summer and rainfall decrease contributed to the increase in the Culex spp. abundance and accelerated the WNV amplification in mosquito vector populations in the following weeks.
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Affiliation(s)
- Ani Ioana Cotar
- Cantacuzino National Institute of Research, Bucharest, Romania
- The European Programme for Public Health Microbiology Training (EUPHEM), European Centre for Disease Prevention and Control (ECDC), Stockholm, Sweden
| | - Elena Falcuta
- Cantacuzino National Institute of Research, Bucharest, Romania
| | | | - Sorin Dinu
- Cantacuzino National Institute of Research, Bucharest, Romania
| | | | - Shlomit Paz
- Department of Geography and Environmental Studies, University of Haifa, Abba Hushi road 199, Mt. Carmel, 3498838, Haifa, Israel.
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Stilianakis NI, Syrris V, Petroliagkis T, Pärt P, Gewehr S, Kalaitzopoulou S, Mourelatos S, Baka A, Pervanidou D, Vontas J, Hadjichristodoulou C. Identification of Climatic Factors Affecting the Epidemiology of Human West Nile Virus Infections in Northern Greece. PLoS One 2016; 11:e0161510. [PMID: 27631082 PMCID: PMC5025206 DOI: 10.1371/journal.pone.0161510] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 08/05/2016] [Indexed: 01/07/2023] Open
Abstract
Climate can affect the geographic and seasonal patterns of vector-borne disease incidence such as West Nile Virus (WNV) infections. We explore the association between climatic factors and the occurrence of West Nile fever (WNF) or West Nile neuro-invasive disease (WNND) in humans in Northern Greece over the years 2010–2014. Time series over a period of 30 years (1979–2008) of climatic data of air temperature, relative humidity, soil temperature, volumetric soil water content, wind speed, and precipitation representing average climate were obtained utilising the ECMWF’s (European Centre for Medium-Range Weather Forecasts) Re-Analysis (ERA-Interim) system allowing for a homogeneous set of data in time and space. We analysed data of reported human cases of WNF/WNND and Culex mosquitoes in Northern Greece. Quantitative assessment resulted in identifying associations between the above climatic variables and reported human cases of WNF/WNND. A substantial fraction of the cases was linked to the upper percentiles of the distribution of air and soil temperature for the period 1979–2008 and the lower percentiles of relative humidity and soil water content. A statistically relevant relationship between the mean weekly value climatic anomalies of wind speed (negative association), relative humidity (negative association) and air temperature (positive association) over 30 years, and reported human cases of WNF/WNND during the period 2010–2014 could be shown. A negative association between the presence of WNV infected Culex mosquitoes and wind speed could be identified. The statistically significant associations could also be confirmed for the week the WNF/WNND human cases appear and when a time lag of up to three weeks was considered. Similar statistically significant associations were identified with the weekly anomalies of the maximum and minimum values of the above climatic factors. Utilising the ERA-Interim re-analysis methodology it could be shown that besides air temperature, climatic factors such as soil temperature, relative humidity, soil water content and wind speed may affect the epidemiology of WNV.
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Affiliation(s)
- Nikolaos I. Stilianakis
- Joint Research Centre, European Commission, Ispra (VA), Italy
- Department of Biometry and Epidemiology, University of Erlangen-Nuremberg, Erlangen, Germany
- * E-mail:
| | | | | | - Peeter Pärt
- Joint Research Centre, European Commission, Ispra (VA), Italy
| | | | | | | | - Agoritsa Baka
- Hellenic Centre for Disease Control and Prevention (KEELPNO), Athens, Greece
| | - Danai Pervanidou
- Hellenic Centre for Disease Control and Prevention (KEELPNO), Athens, Greece
| | - John Vontas
- Institute of Molecular Biology and Biotechnology, Foundation for Research and Technology-Hellas, Heraklion, Greece
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Chaskopoulou A, L'Ambert G, Petric D, Bellini R, Zgomba M, Groen TA, Marrama L, Bicout DJ. Ecology of West Nile virus across four European countries: review of weather profiles, vector population dynamics and vector control response. Parasit Vectors 2016; 9:482. [PMID: 27590848 PMCID: PMC5009705 DOI: 10.1186/s13071-016-1736-6] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/18/2016] [Accepted: 08/01/2016] [Indexed: 11/26/2022] Open
Abstract
West Nile virus (WNV) represents a serious burden to human and animal health because of its capacity to cause unforeseen and large epidemics. Until 2004, only lineage 1 and 3 WNV strains had been found in Europe. Lineage 2 strains were initially isolated in 2004 (Hungary) and in 2008 (Austria) and for the first time caused a major WNV epidemic in 2010 in Greece with 262 clinical human cases and 35 fatalities. Since then, WNV lineage 2 outbreaks have been reported in several European countries including Italy, Serbia and Greece. Understanding the interaction of ecological factors that affect WNV transmission is crucial for preventing or decreasing the impact of future epidemics. The synchronous co-occurrence of competent mosquito vectors, virus, bird reservoir hosts, and susceptible humans is necessary for the initiation and propagation of an epidemic. Weather is the key abiotic factor influencing the life-cycles of the mosquito vector, the virus, the reservoir hosts and the interactions between them. The purpose of this paper is to review and compare mosquito population dynamics, and weather conditions, in three ecologically different contexts (urban/semi-urban, rural/agricultural, natural) across four European countries (Italy, France, Serbia, Greece) with a history of WNV outbreaks. Local control strategies will be described as well. Improving our understanding of WNV ecology is a prerequisite step for appraising and optimizing vector control strategies in Europe with the ultimate goal to minimize the probability of WNV infection.
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Affiliation(s)
- Alexandra Chaskopoulou
- USDA-ARS, European Biological Control Laboratory, Tsimiski 43, Thessaloniki, 54623, Greece
| | - Gregory L'Ambert
- EID Mediterranee, 165 Avenue Paul Rimbaud, Montpellier, 34184, France
| | - Dusan Petric
- Faculty of Agriculture, Laboratory for Medical Entomology, University of Novi Sad, Trg D. Obradovica 8, Novi Sad, 21000, Serbia
| | - Romeo Bellini
- Centro Agricoltura Ambiente "G. Nicoli", Via Argini Nord 3351, Crevalcore, 40014, Italy
| | - Marija Zgomba
- Faculty of Agriculture, Laboratory for Medical Entomology, University of Novi Sad, Trg D. Obradovica 8, Novi Sad, 21000, Serbia
| | - Thomas A Groen
- Faculty of Geo-Information Science and Earth Observation, University of Twente, PO Box 217, Enschede, 7500 AE, The Netherlands
| | - Laurence Marrama
- ECDC, European Centre for Disease Prevention and Control, Tomtebodavagen 11A, Stockholm, 17183, Sweden
| | - Dominique J Bicout
- Biomathematics and Epidemiology EPSP-TIMC, VetAgro Sup, Veterinary Campus of Lyon, Marcy l'Etoile, F-69280, France. .,Laue-Langevin Institute, Theory Group, Grenoble cedex 9, F-38042, France.
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74
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Reperant LA, Brown IH, Haenen OL, de Jong MD, Osterhaus ADME, Papa A, Rimstad E, Valarcher JF, Kuiken T. Companion Animals as a Source of Viruses for Human Beings and Food Production Animals. J Comp Pathol 2016; 155:S41-53. [PMID: 27522300 DOI: 10.1016/j.jcpa.2016.07.006] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 07/04/2016] [Accepted: 07/07/2016] [Indexed: 01/12/2023]
Abstract
Companion animals comprise a wide variety of species, including dogs, cats, horses, ferrets, guinea pigs, reptiles, birds and ornamental fish, as well as food production animal species, such as domestic pigs, kept as companion animals. Despite their prominent place in human society, little is known about the role of companion animals as sources of viruses for people and food production animals. Therefore, we reviewed the literature for accounts of infections of companion animals by zoonotic viruses and viruses of food production animals, and prioritized these viruses in terms of human health and economic importance. In total, 138 virus species reportedly capable of infecting companion animals were of concern for human and food production animal health: 59 of these viruses were infectious for human beings, 135 were infectious for food production mammals and birds, and 22 were infectious for food production fishes. Viruses of highest concern for human health included hantaviruses, Tahyna virus, rabies virus, West Nile virus, tick-borne encephalitis virus, Crimean-Congo haemorrhagic fever virus, Aichi virus, European bat lyssavirus, hepatitis E virus, cowpox virus, G5 rotavirus, influenza A virus and lymphocytic choriomeningitis virus. Viruses of highest concern for food production mammals and birds included bluetongue virus, African swine fever virus, foot-and-mouth disease virus, lumpy skin disease virus, Rift Valley fever virus, porcine circovirus, classical swine fever virus, equine herpesvirus 9, peste des petits ruminants virus and equine infectious anaemia virus. Viruses of highest concern for food production fishes included cyprinid herpesvirus 3 (koi herpesvirus), viral haemorrhagic septicaemia virus and infectious pancreatic necrosis virus. Of particular concern as sources of zoonotic or food production animal viruses were domestic carnivores, rodents and food production animals kept as companion animals. The current list of viruses provides an objective basis for more in-depth analysis of the risk of companion animals as sources of viruses for human and food production animal health.
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Affiliation(s)
- L A Reperant
- Department of Viroscience, Erasmus Medical Centre, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - I H Brown
- Animal and Plant Health Agency Weybridge, New Haw, Addlestone, Surrey, UK
| | - O L Haenen
- National Reference Laboratory for Fish, Shellfish and Crustacean Diseases, Central Veterinary Institute of Wageningen UR, PO Box 65, 8200 AB Lelystad, The Netherlands
| | - M D de Jong
- Department of Medical Microbiology, Academic Medical Centre, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands
| | - A D M E Osterhaus
- Department of Viroscience, Erasmus Medical Centre, PO Box 2040, 3000 CA Rotterdam, The Netherlands
| | - A Papa
- Department of Microbiology, Medical School Aristotle University of Thessaloniki, Thessaloniki, Greece
| | - E Rimstad
- Department of Food Safety and Infection Biology, University of Life Sciences, Oslo, Norway
| | - J-F Valarcher
- Department of Virology, Immunology, and Parasitology, National Veterinary Institute, Uppsala, Sweden
| | - T Kuiken
- Department of Viroscience, Erasmus Medical Centre, PO Box 2040, 3000 CA Rotterdam, The Netherlands.
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75
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Abstract
The epidemics of Ebola virus in West Africa and Zika virus in America highlight how viruses can explosively emerge into new territories. These epidemics also exposed how unprepared we are to handle infectious disease emergencies. This is also true when we consider hypothesized new clinical features of infection, such as the associations between Zika virus infection and severe neurological disease, including microcephaly and Guillain-Barré syndrome. On the surface, these pathologies appear to be new features of Zika virus infection, however, causal relationships have not yet been established. Decades of limited Zika virus research are making us scramble to determine the true drivers behind the epidemic, often at the expense of over-speculation without credible evidence. Here we review the literature and find no conclusive evidence at this time for significant biological differences between the American Zika virus strains and those circulating elsewhere. Rather, the epidemic scale in the Americas may be facilitated by an abnormally warm climate, dense human and mosquito populations, and previous exposure to other viruses. Severe disease associated with Zika virus may therefore not be a new trait for the virus, rather it may have been overlooked due to previously small outbreaks. Much of the recent panic regarding Zika virus has been about the Olympics in Brazil. We do not find any substantial evidence that the Olympics will result in a significant number of new Zika virus infections (~10 predicted) or that the Olympics will promote further epidemic spread over what is already expected. The Zika virus epidemic in the Americas is a serious situation and decisions based on solid scientific evidence - not hyped media speculations - are required for effective outbreak response.
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Affiliation(s)
- Nathan D. Grubaugh
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, 92037, USA
| | - Kristian G. Andersen
- Department of Immunology and Microbial Science, The Scripps Research Institute, La Jolla, CA, 92037, USA
- Scripps Translational Science Institute, La Jolla, CA, 92037, USA
- Broad Institute of MIT and Harvard, Cambridge, MA, 02142, USA
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76
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Vázquez A, Herrero L, Negredo A, Hernández L, Sánchez-Seco MP, Tenorio A. Real time PCR assay for detection of all known lineages of West Nile virus. J Virol Methods 2016; 236:266-270. [PMID: 27481597 DOI: 10.1016/j.jviromet.2016.07.026] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 07/29/2016] [Accepted: 07/29/2016] [Indexed: 11/17/2022]
Abstract
West Nile virus (WNV) is one of the most widespread arbovirus and a large variety of WNV strains and lineages have been described. The molecular methods for the diagnosis of WNV target mainly lineages 1 and 2, which have caused outbreaks in humans, equines and birds. But the last few years new and putative WNV lineages of unknown pathogenicity have been described. Here we describe a new sensitive and specific real-time PCR assay for the detection and quantification of all the WNV lineages described until now. Primers and probe were designed in the 3'-untranslated region (3'-UTR) of the WNV genome and were designed to match all sequenced WNV strains perfectly. The sensitivity of the assay ranged from 1,5 to 15 copies per reaction depending on the WNV lineage tested. The method was validated for WNV diagnosis using different viral strains, human samples (cerebrospinal fluid, biopsies, serum and plasma) and mosquito pools. The assay did not amplify any other phylogenetically or symptomatically related viruses. All of the above make it a very suitable tool for the diagnosis of WNV and for surveillance studies.
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Affiliation(s)
- Ana Vázquez
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain.
| | - Laura Herrero
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - Anabel Negredo
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - Lourdes Hernández
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - María Paz Sánchez-Seco
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
| | - Antonio Tenorio
- Laboratory of Arboviruses and Imported Viral Diseases, National Centre for Microbiology, Instituto de Salud Carlos III, Ctra. Majadahonda-Pozuelo, km. 2, 28220 Majadahonda, Madrid, Spain
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77
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David S, Abraham AM. Epidemiological and clinical aspects on West Nile virus, a globally emerging pathogen. Infect Dis (Lond) 2016; 48:571-86. [PMID: 27207312 DOI: 10.3109/23744235.2016.1164890] [Citation(s) in RCA: 56] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
Abstract
BACKGROUND Since the isolation of West Nile virus (WNV) in 1937, in Uganda, it has spread globally, causing significant morbidity and mortality. While birds serve as amplifier hosts, mosquitoes of the Culex genus function as vectors. Humans and horses are dead end hosts. The clinical manifestations of West Nile infection in humans range from asymptomatic illness to West Nile encephalitis. METHODS The laboratory offers an array of tests, the preferred method being detection of RNA and serum IgM for WNV, which, if detected, confirms the clinical diagnosis. Although no definitive antiviral therapy and vaccine are available for humans, many approaches are being studied. STUDY This article will review the current literature of the natural cycle, geographical distribution, virology, replication cycle, molecular epidemiology, pathogenesis, laboratory diagnosis, clinical manifestations, blood donor screening for WNV, treatment, prevention and vaccines.
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Affiliation(s)
- Shoba David
- a Department of Clinical Virology , Christian Medical College , Vellore , Tamil Nadu , India
| | - Asha Mary Abraham
- a Department of Clinical Virology , Christian Medical College , Vellore , Tamil Nadu , India
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78
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Pisani G, Cristiano K, Pupella S, Liumbruno GM. West Nile Virus in Europe and Safety of Blood Transfusion. Transfus Med Hemother 2016; 43:158-67. [PMID: 27403087 DOI: 10.1159/000446219] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2016] [Accepted: 04/15/2016] [Indexed: 12/26/2022] Open
Abstract
West Nile virus (WNV) has become an increasing issue in the transfusion setting since 2002, when it was firstly shown in the USA that it can be transmitted through blood transfusion. Since then, several precautionary measures have been introduced in Europe in order to reduce the possible risk of transmission via transfusion/solid organ transplantation. In addition, the epidemiological surveillance has been tightened and the network for communication of human WNV cases strengthened. This review will focus on WNV circulation and the safety of blood in Europe.
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Affiliation(s)
- Giulio Pisani
- National Center for Immunobiologicals, Research and Evaluation, Istituto Superiore di Sanità, Rome, Italy
| | - Karen Cristiano
- National Center for Immunobiologicals, Research and Evaluation, Istituto Superiore di Sanità, Rome, Italy
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79
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Marini G, Poletti P, Giacobini M, Pugliese A, Merler S, Rosà R. The Role of Climatic and Density Dependent Factors in Shaping Mosquito Population Dynamics: The Case of Culex pipiens in Northwestern Italy. PLoS One 2016; 11:e0154018. [PMID: 27105065 PMCID: PMC4841511 DOI: 10.1371/journal.pone.0154018] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2016] [Accepted: 04/07/2016] [Indexed: 11/19/2022] Open
Abstract
Culex pipiens mosquito is a species widely spread across Europe and represents a competent vector for many arboviruses such as West Nile virus (WNV), which has been recently circulating in many European countries, causing hundreds of human cases. In order to identify the main determinants of the high heterogeneity in Cx. pipiens abundance observed in Piedmont region (Northwestern Italy) among different seasons, we developed a density-dependent stochastic model that takes explicitly into account the role played by temperature, which affects both developmental and mortality rates of different life stages. The model was calibrated with a Markov chain Monte Carlo approach exploring the likelihood of recorded capture data gathered in the study area from 2000 to 2011; in this way, we disentangled the role played by different seasonal eco-climatic factors in shaping the vector abundance. Illustrative simulations have been performed to forecast likely changes if temperature or density–dependent inputs would change. Our analysis suggests that inter-seasonal differences in the mosquito dynamics are largely driven by different temporal patterns of temperature and seasonal-specific larval carrying capacities. Specifically, high temperatures during early spring hasten the onset of the breeding season and increase population abundance in that period, while, high temperatures during the summer can decrease population size by increasing adult mortality. Higher densities of adult mosquitoes are associated with higher larval carrying capacities, which are positively correlated with spring precipitations. Finally, an increase in larval carrying capacity is expected to proportionally increase adult mosquito abundance.
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Affiliation(s)
- Giovanni Marini
- Department of Mathematics, University of Trento, Trento, Italy
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige (TN), Italy
- * E-mail:
| | - Piero Poletti
- Bruno Kessler Foundation, Trento, Italy
- Dondena Centre for Research on Social Dynamics and Public Policy, Department of Policy Analysis and Public Management, Universitá Commerciale L. Bocconi, Milan, Italy
| | - Mario Giacobini
- Department of Veterinary Sciences, University of Torino, Torino, Italy
| | - Andrea Pugliese
- Department of Mathematics, University of Trento, Trento, Italy
| | | | - Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige (TN), Italy
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80
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Volz A, Lim S, Kaserer M, Lülf A, Marr L, Jany S, Deeg CA, Pijlman GP, Koraka P, Osterhaus ADME, Martina BE, Sutter G. Immunogenicity and protective efficacy of recombinant Modified Vaccinia virus Ankara candidate vaccines delivering West Nile virus envelope antigens. Vaccine 2016; 34:1915-26. [PMID: 26939903 DOI: 10.1016/j.vaccine.2016.02.042] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2015] [Revised: 02/14/2016] [Accepted: 02/16/2016] [Indexed: 12/30/2022]
Abstract
West Nile virus (WNV) cycles between insects and wild birds, and is transmitted via mosquito vectors to horses and humans, potentially causing severe neuroinvasive disease. Modified Vaccinia virus Ankara (MVA) is an advanced viral vector for developing new recombinant vaccines against infectious diseases and cancer. Here, we generated and evaluated recombinant MVA candidate vaccines that deliver WNV envelope (E) antigens and fulfil all the requirements to proceed to clinical testing in humans. Infections of human and equine cell cultures with recombinant MVA demonstrated efficient synthesis and secretion of WNV envelope proteins in mammalian cells non-permissive for MVA replication. Prime-boost immunizations in BALB/c mice readily induced circulating serum antibodies binding to recombinant WNV E protein and neutralizing WNV in tissue culture infections. Vaccinations in HLA-A2.1-/HLA-DR1-transgenic H-2 class I-/class II-knockout mice elicited WNV E-specific CD8+ T cell responses. Moreover, the MVA-WNV candidate vaccines protected C57BL/6 mice against lineage 1 and lineage 2 WNV infection and induced heterologous neutralizing antibodies. Thus, further studies are warranted to evaluate these recombinant MVA-WNV vaccines in other preclinical models and use them as candidate vaccine in humans.
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Affiliation(s)
- Asisa Volz
- German Centre for Infection Research (DZIF), Institute for Infectious Diseases and Zoonoses, LMU University of Munich, Veterinaerstrasse 13, D-80539 Munich, Germany
| | - Stephanie Lim
- Viroscience Lab, Erasmus Medical Center, Rotterdam, The Netherlands; Artemis One Health Research Institute, Utrecht, The Netherlands
| | - Martina Kaserer
- German Centre for Infection Research (DZIF), Institute for Infectious Diseases and Zoonoses, LMU University of Munich, Veterinaerstrasse 13, D-80539 Munich, Germany
| | - Anna Lülf
- German Centre for Infection Research (DZIF), Institute for Infectious Diseases and Zoonoses, LMU University of Munich, Veterinaerstrasse 13, D-80539 Munich, Germany
| | - Lisa Marr
- German Centre for Infection Research (DZIF), Institute for Infectious Diseases and Zoonoses, LMU University of Munich, Veterinaerstrasse 13, D-80539 Munich, Germany
| | - Sylvia Jany
- German Centre for Infection Research (DZIF), Institute for Infectious Diseases and Zoonoses, LMU University of Munich, Veterinaerstrasse 13, D-80539 Munich, Germany
| | - Cornelia A Deeg
- Institute for Animal Physiology, LMU University of Munich, Munich, Germany
| | - Gorben P Pijlman
- Laboratory of Virology, Wageningen University, Wageningen, The Netherlands
| | - Penelope Koraka
- Viroscience Lab, Erasmus Medical Center, Rotterdam, The Netherlands
| | - Albert D M E Osterhaus
- Viroscience Lab, Erasmus Medical Center, Rotterdam, The Netherlands; Artemis One Health Research Institute, Utrecht, The Netherlands
| | - Byron E Martina
- Viroscience Lab, Erasmus Medical Center, Rotterdam, The Netherlands; Artemis One Health Research Institute, Utrecht, The Netherlands
| | - Gerd Sutter
- German Centre for Infection Research (DZIF), Institute for Infectious Diseases and Zoonoses, LMU University of Munich, Veterinaerstrasse 13, D-80539 Munich, Germany.
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81
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Szentpáli-Gavallér K, Lim SM, Dencső L, Bányai K, Koraka P, Osterhaus ADME, Martina BEE, Bakonyi T, Bálint Á. In Vitro and in Vivo Evaluation of Mutations in the NS Region of Lineage 2 West Nile Virus Associated with Neuroinvasiveness in a Mammalian Model. Viruses 2016; 8:v8020049. [PMID: 26907325 PMCID: PMC4776204 DOI: 10.3390/v8020049] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2015] [Revised: 01/19/2016] [Accepted: 02/09/2016] [Indexed: 12/25/2022] Open
Abstract
West Nile virus (WNV) strains may differ significantly in neuroinvasiveness in vertebrate hosts. In contrast to genetic lineage 1 WNVs, molecular determinants of pathogenic lineage 2 strains have not been experimentally confirmed so far. A full-length infectious clone of a neurovirulent WNV lineage 2 strain (578/10; Central Europe) was generated and amino acid substitutions that have been shown to attenuate lineage 1 WNVs were introduced into the nonstructural proteins (NS1 (P250L), NS2A (A30P), NS3 (P249H) NS4B (P38G, C102S, E249G)). The mouse neuroinvasive phenotype of each mutant virus was examined following intraperitoneal inoculation of C57BL/6 mice. Only the NS1-P250L mutation was associated with a significant attenuation of virulence in mice compared to the wild-type. Multiplication kinetics in cell culture revealed significantly lower infectious virus titres for the NS1 mutant compared to the wild-type, as well as significantly lower amounts of positive and negative stranded RNA.
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Affiliation(s)
| | - Stephanie M Lim
- Viroscience Laboratory, Erasmus Medical Centre, 3015CN, Rotterdam, The Netherlands.
| | - László Dencső
- Veterinary Diagnostic Directorate, National Food Chain Safety Office, H-1143, Budapest, Hungary.
| | - Krisztián Bányai
- Institute for Veterinary Medical Research, Centre for Agricultural Research, Hungarian Academy of Sciences, H-1143, Budapest, Hungary.
| | - Penelope Koraka
- Viroscience Laboratory, Erasmus Medical Centre, 3015CN, Rotterdam, The Netherlands.
| | | | - Byron E E Martina
- Viroscience Laboratory, Erasmus Medical Centre, 3015CN, Rotterdam, The Netherlands.
| | - Tamás Bakonyi
- Department of Microbiology and Infectious Diseases, Faculty of Veterinary Science, Szent István University, H-1143, Budapest, Hungary.
- Viral Zoonoses, Emerging and Vector-Borne Infections Group, Institute of Virology, University of Veterinary Medicine, A-1210, Vienna, Austria.
| | - Ádám Bálint
- Veterinary Diagnostic Directorate, National Food Chain Safety Office, H-1143, Budapest, Hungary.
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82
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West Nile virus-neutralizing antibodies in wild birds from southern Spain. Epidemiol Infect 2016; 144:1907-11. [PMID: 26846720 DOI: 10.1017/s0950268816000133] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022] Open
Abstract
West Nile virus (WNV) is an emerging vector-borne arbovirus with a zoonotic life-cycle whose main reservoir hosts are birds. In humans and horses, WNV infections rarely result in clinical disease but on occasions - depending on factors such as climatic conditions, insect communities and background immunity levels in local populations - they can lead to outbreaks that threaten public and animal health. We tested for the presence of WNV antibodies in 149 birds belonging to 32 different species. Samples were first tested using a bird-specific ELISA kit and then both positive and doubtful results were confirmed by neutralization tests using WNV and Usutu virus. WNV antibodies were confirmed in a resident Sylvia melanocephala juvenile, supporting the idea of local transmission of WNV in southern Spain in 2013. In addition, the serum from an adult blackbird (Turdus merula) showed neutralization of both WNV and Usutu virus. We discuss our results in light of the occurrence of WNV on horse farms in southern Spain in 2013.
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83
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Gonzalez-Medina S, Alzola R, Newton JR. Suspect West Nile virus encephalomyelitis in an imported horse in the UK. EQUINE VET EDUC 2016. [DOI: 10.1111/eve.12545] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- S. Gonzalez-Medina
- Department of Epidemiology and Disease Surveillance; Animal Health Trust; Kentford Suffolk UK
| | - R. Alzola
- Oakham Equine Hospital; Oakham Rutland UK
| | - J. R. Newton
- Department of Epidemiology and Disease Surveillance; Animal Health Trust; Kentford Suffolk UK
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84
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Piron M, Plasencia A, Fleta-Soriano E, Martinez A, Martinez JP, Torner N, Sauleda S, Meyerhans A, Escalé J, Trilla A, Pumarola T, Martinez MJ. Low Seroprevalence of West Nile Virus in Blood Donors from Catalonia, Spain. Vector Borne Zoonotic Dis 2015; 15:782-4. [PMID: 26581013 DOI: 10.1089/vbz.2015.1787] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
West Nile virus (WNV) is an emerging arbovirus first recognized in Europe in the 1950s. Since then, outbreaks have been reported in several European countries. In 2010, the first WNV outbreak was recorded in Spain, affecting the southern part of the country. We conducted a seroprevalence study in the Catalonia region (northeastern Spain), an area considered at high risk of arbovirus transmission. A total of 800 serum samples from blood donors were collected and screened for antibodies against WNV by enzyme-linked immunosorbent assay (ELISA) and confirmed by a microneutralization assay. More than 50 samples tested positive by ELISA, but only one sample contained neutralizing antibodies against WNV and was obtained from a donor native of Pakistan. The low seroprevalence detected may serve as reference baseline data for monitoring WNV activity in our region in future years.
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Affiliation(s)
- Maria Piron
- 1 Transfusion Safety Laboratory, Catalonian Blood and Tissue Bank (BST) , Barcelona, Spain
| | - Antoni Plasencia
- 2 ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona , Barcelona, Spain
| | - Eric Fleta-Soriano
- 3 Infection Biology Group, Department of Experimental and Health Sciences, Universitat Pompeu Fabra , Barcelona, Spain
| | - Ana Martinez
- 4 Public Health Agency of Catalonia, Generalitat of Catalonia , Barcelona, Spain
| | - Javier P Martinez
- 3 Infection Biology Group, Department of Experimental and Health Sciences, Universitat Pompeu Fabra , Barcelona, Spain
| | - Nuria Torner
- 4 Public Health Agency of Catalonia, Generalitat of Catalonia , Barcelona, Spain
| | - Silvia Sauleda
- 1 Transfusion Safety Laboratory, Catalonian Blood and Tissue Bank (BST) , Barcelona, Spain
| | - Andreas Meyerhans
- 3 Infection Biology Group, Department of Experimental and Health Sciences, Universitat Pompeu Fabra , Barcelona, Spain .,5 Institució Catalana de Recerca i Estudis Avançats (ICREA) , Barcelona, Spain
| | - Josefina Escalé
- 6 Department of Clinical Microbiology, Hospital Clínic , Barcelona, Spain
| | - Antoni Trilla
- 7 Department of Preventive Medicine, Hospital Clínic , Barcelona, Spain
| | - Tomás Pumarola
- 8 Microbiology Department, Hospital Universitario Vall d'Hebron , Barcelona, Spain
| | - Miguel Julian Martinez
- 2 ISGlobal, Barcelona Centre for International Health Research (CRESIB), Hospital Clínic, Universitat de Barcelona , Barcelona, Spain .,6 Department of Clinical Microbiology, Hospital Clínic , Barcelona, Spain
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85
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Dridi M, Van Den Berg T, Lecollinet S, Lambrecht B. Evaluation of the pathogenicity of West Nile virus (WNV) lineage 2 strains in a SPF chicken model of infection: NS3-249Pro mutation is neither sufficient nor necessary for conferring virulence. Vet Res 2015; 46:130. [PMID: 26518144 PMCID: PMC4628354 DOI: 10.1186/s13567-015-0257-1] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2015] [Accepted: 09/21/2015] [Indexed: 01/28/2023] Open
Abstract
Lineage 2 West Nile virus (WNV) strains were reported for the first time in Europe in 2004. Despite an almost silent circulation around their entry point in Hungary, an upsurge of pathogenicity occurred in 2010 as 262 people suffered from neuroinvasive disease in Greece. This increase in virulence was imputed to the emergence of a His249Pro mutation in the viral NS3 helicase, as previously evidenced in American crows experimentally infected with the prototype lineage 1 North-American WNV strain. However, since 2003, WNV strains bearing the NS3Pro genotype are regularly isolated in Western-Mediterranean countries without being correlated to any virulent outbreak in vertebrates. We thus sought to evaluate the weight of the NS3249Pro genotype as a virulence marker of WNV in an in vivo avian model of WNV infection. We therefore characterized three genetically-related Eastern-Europe lineage 2 WNV strains in day-old specific pathogen-free (SPF) chickens: Hun2004 and Aus2008 which are both characterized by a NS3249His genotype, and Gr2011 which is characterized by a NS3249Pro genotype. Unlike Hun2004 and Aus2008, Gr2011 was weakly virulent in SPF chicks as Gr2011-induced viremia was lower and waned quicklier than in the Hun2004 and Aus2008 groups. Overall, this study showed that the presence of a proline residue at position 249 of the viral NS3 helicase is neither sufficient nor necessary to confer pathogenicity to any given lineage 2 WNV strain in birds.
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Affiliation(s)
- Maha Dridi
- Operational Direction of Viral Diseases, CODA-CERVA-Veterinary and Agrochemical Research Centre, 99 Groeselenberg, 1180, Brussels, Belgium.
| | - Thierry Van Den Berg
- Operational Direction of Viral Diseases, CODA-CERVA-Veterinary and Agrochemical Research Centre, 99 Groeselenberg, 1180, Brussels, Belgium.
| | - Sylvie Lecollinet
- UPE, UMR1161 Virologie, Institut National de la Recherche Agronomique (INRA), Agence Nationale de Sécurité Sanitaire de l'alimentation, de l'environnement et du travail (ANSES), Ecole Nationale Vétérinaire d'Alfort (ENVA), 14 rue Pierre et Marie Curie, 94701, Maisons-Alfort, France.
| | - Benedicte Lambrecht
- Operational Direction of Viral Diseases, CODA-CERVA-Veterinary and Agrochemical Research Centre, 99 Groeselenberg, 1180, Brussels, Belgium.
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86
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Gamino V, Escribano-Romero E, Blázquez AB, Gutiérrez-Guzmán AV, Martín-Acebes MÁ, Saiz JC, Höfle U. Experimental North American West Nile Virus Infection in the Red-legged Partridge (Alectoris rufa). Vet Pathol 2015; 53:585-93. [PMID: 26508695 DOI: 10.1177/0300985815612554] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
After the introduction of West Nile virus (WNV) into North America, bird mortalities associated with West Nile disease have dramatically increased in this continent and, to a lesser extent, in Europe. The different West Nile disease incidence in birds in these 2 continents demands an explanation, and experimental studies can provide important information. The authors inoculated thirteen 9-week-old red-legged partridges (Alectoris rufa) with 10(7)plaque-forming units of a WNV strain isolated in New York in 1999. The objective was to study the pathogenesis of the infection in a native Euro-Mediterranean bird species with a WNV strain known to be highly pathogenic for numerous native American bird species. Additionally, the authors evaluated the dynamics of inflammatory cell activation and recruitment into the brain. WNV was detected in tissues 3 days postinoculation (dpi), and the birds developed macroscopic and microscopic lesions. Two partridges succumbed to the disease. The most affected tissues were the heart, brain, and spinal cord. The main microscopic findings were the presence of mononuclear infiltrates in the heart and brain, gliosis, and degeneration and necrosis of cardiomyocytes and neurons. These lesions were aggravated in the birds that died or were euthanized 7 dpi or later. In the brain, there was an upregulation of microglial cells and astrocytes and an increase in the number of T cells, especially after 7 dpi. These results show that this WNV strain is of moderate virulence for the red-legged partridge and that WNV-infected red-legged partridges develop an immune cell response in the brain similar to that of mammals.
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Affiliation(s)
- V Gamino
- SaBio, Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - E Escribano-Romero
- Departamento de Biotecnología, Instituto Nacional de Investigaciones Agrarias, Madrid, Spain
| | - A-B Blázquez
- Departamento de Biotecnología, Instituto Nacional de Investigaciones Agrarias, Madrid, Spain
| | - A-V Gutiérrez-Guzmán
- SaBio, Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain
| | - M-Á Martín-Acebes
- Departamento de Biotecnología, Instituto Nacional de Investigaciones Agrarias, Madrid, Spain
| | - J-C Saiz
- Departamento de Biotecnología, Instituto Nacional de Investigaciones Agrarias, Madrid, Spain
| | - U Höfle
- SaBio, Instituto de Investigación en Recursos Cinegéticos, IREC (CSIC-UCLM-JCCM), Ciudad Real, Spain
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Fortuna C, Remoli ME, Di Luca M, Severini F, Toma L, Benedetti E, Bucci P, Montarsi F, Minelli G, Boccolini D, Romi R, Ciufolini MG. Experimental studies on comparison of the vector competence of four Italian Culex pipiens populations for West Nile virus. Parasit Vectors 2015; 8:463. [PMID: 26383834 PMCID: PMC4574231 DOI: 10.1186/s13071-015-1067-z] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2015] [Accepted: 09/01/2015] [Indexed: 12/25/2022] Open
Abstract
Background West Nile virus (WNV) is a vector-borne disease responsible for causing epidemics in many areas of the world. The virus is maintained in nature by an enzootic bird-mosquito-bird cycle and occasionally transmitted to other hosts, such as equines and humans. Culex species, in particular the ubiquitous species Culex pipiens is thought to play a major vector role both in enzootic and epizootic maintenance and transmission of WNV. Introduced in Europe in recent years, since 2008 WNV has been stably circulating mainly in the Northeastern regions of Italy, although sporadic equine and/or human cases, as well as WNV infected Cx. pipiens pools, have been recorded in other Italian areas. The scope of our study was to evaluate the potential competence of some Italian populations of Cx. pipiens to transmit WNV and to assess their ability for vertical transmission of the virus. For this purpose four Italian populations, from different areas, were experimentally infected. Methods After the infectious blood meal, fed females were monitored for 32 days to determine the length of viral extrinsic incubation period. WNV titre of infected mosquitoes was evaluated both by quantitative Real Time PCR and viral titration by Plaque Forming Units/ml (PFU/mL) in VERO cells. Potential Infection, Dissemination, Transmission rates (IR, DR, TR) were assessed by detection of the virus in body, legs plus wings and saliva of the fed females, respectively. Results All tested populations were susceptible to the WNV infection. The viral presence in legs and wings demonstrated the ability of WNV to disseminate in the mosquitoes. Viral RNA was detected in the saliva of tested populations. No significant differences in TR values were observed among the four studied populations. The offspring of the Cx. pipiens infected females were WNV negative. Conclusions Our study addressed an important issue in the knowledge on the complex WNV-vector relationships in Italy, indicating that all Italian Cx. pipiens populations tested exhibited vector competence for WNV. Further studies should be performed in order to better clarify the role of other factors (vector density, climatic conditions, reservoir presence etc.) in order to predict where and when WNV outbreaks could occur.
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Affiliation(s)
- Claudia Fortuna
- Unit of Viral diseases and attenuated vaccine, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Maria Elena Remoli
- Unit of Viral diseases and attenuated vaccine, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Marco Di Luca
- Unit of Vector-borne Diseases and International Health, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Francesco Severini
- Unit of Vector-borne Diseases and International Health, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Luciano Toma
- Unit of Vector-borne Diseases and International Health, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Eleonora Benedetti
- Unit of Viral diseases and attenuated vaccine, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Paola Bucci
- Unit of Viral diseases and attenuated vaccine, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Fabrizio Montarsi
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, PD, Italy.
| | - Giada Minelli
- National Centre for Epidemiology, Surveillance and Health Promotion, Unit of Statistics Istituto Superiore di Sanità, Rome, Italy.
| | - Daniela Boccolini
- Unit of Vector-borne Diseases and International Health, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Roberto Romi
- Unit of Vector-borne Diseases and International Health, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
| | - Maria Grazia Ciufolini
- Unit of Viral diseases and attenuated vaccine, Department of Infectious, Parasitic and Immune-Mediated Diseases Istituto Superiore di Sanità, Rome, Italy.
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88
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Mweene-Ndumba I, Siziya S, Monze M, Mazaba ML, Masaninga F, Songolo P, Mwaba P, Babaniyi OA. Seroprevalence of West Nile Virus specific IgG and IgM antibodies in North-Western and Western provinces of Zambia. Afr Health Sci 2015; 15:803-9. [PMID: 26957968 DOI: 10.4314/ahs.v15i3.14] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022] Open
Abstract
BACKGROUND West Nile Virus (WNV) infection has been reported worldwide, including in Africa but its existence in Zambia is unknown. Symptoms for the virus include headache, myalgia, arthralgia and rash. OBJECTIVES This study aimed to determine the seroprevalence of WNV and its correlates. METHODS A cross sectional study was conducted in North-Western and Western provinces of Zambia. Samples were subjected to IgG and IgM antibodies testing against WNV. Logistic regression analyses were conducted to determine magnitudes of association. RESULTS A total of 3,625 of persons participated in the survey out of which 10.3% had WNV infection. Farmers were 20% (AOR=0.80; 95% CI [0.64, 0.99]) less likely to have infection compared to students. Meanwhile participants who lived in grass roofed houses were 2.97 (AOR=2.97; 95% CI [1.81, 4.88]) times more likely to be infected than those who lived in asbestos roofed houses. IRS was associated with reduced risk of infection (AOR=0.81; 95% CI [0.69, 0.94]). Travelling to Angola was associated with the infection [AOR=1.40; 95% CI [1.09, 1.81]. CONCLUSION Spraying houses with insecticide residual spray would minimize mosquito-man contact. Furthermore, surveillance at the border with Angola should be enhanced in order to reduce importation of the virus into the country.
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Affiliation(s)
- Idah Mweene-Ndumba
- Immunization, Vaccines and Emergencies, World Health Organization Country Office, Lusaka, Zambia; Pathology and Microbiology Department, University Teaching Hospital, Lusaka, Zambia
| | - Seter Siziya
- Clinical Sciences Department, School of Medicine, Copperbelt University, Ndola, Zambia; Public Health Department, University Lusaka, Lusaka, Zambia
| | - Mwaka Monze
- Pathology and Microbiology Department, University Teaching Hospital, Lusaka, Zambia
| | - Mazyanga L Mazaba
- Immunization, Vaccines and Emergencies, World Health Organization Country Office, Lusaka, Zambia; Pathology and Microbiology Department, University Teaching Hospital, Lusaka, Zambia
| | - Freddie Masaninga
- Diseases Prevention and Control, World Health Organization Country Office, Lusaka, Zambia
| | - Peter Songolo
- Diseases Prevention and Control, World Health Organization Country Office, Lusaka, Zambia
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Jean Jose Nepomichene TN, Elissa N, Cardinale E, Boyer S. Species Diversity, Abundance, and Host Preferences of Mosquitoes (Diptera: Culicidae) in Two Different Ecotypes of Madagascar With Recent RVFV Transmission. JOURNAL OF MEDICAL ENTOMOLOGY 2015; 52:962-969. [PMID: 26336259 DOI: 10.1093/jme/tjv120] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 07/23/2015] [Indexed: 06/05/2023]
Abstract
Mosquito diversity and abundance were examined in six Madagascan villages in either arid (Toliary II district) or humid (Mampikony district) ecotypes, each with a history of Rift Valley fever virus transmission. Centers for Disease Control and Prevention light traps without CO2 (LT) placed near ruminant parks and animal-baited net trap (NT) baited with either zebu or sheep/goat were used to sample mosquitoes, on two occasions between March 2011 and October 2011. Culex tritaeniorhynchus (Giles) was the most abundant species, followed by Culex antennatus (Becker) and Anopheles squamosus/cydippis (Theobald/de Meillon). These three species comprised more than half of all mosquitoes collected. The NT captured more mosquitoes in diversity and in abundance than the LT, and also caught more individuals of each species, except for An. squamosus/cydippis. Highest diversity and abundance were observed in the humid and warm district of Mampikony. No host preference was highlighted, except for Cx. tritaeniorhynchus presenting a blood preference for zebu baits. The description of species diversity, abundance, and host preference described herein can inform the development of control measures to reduce the risk of mosquito-borne diseases in Madagascar.
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Affiliation(s)
- Thiery Nirina Jean Jose Nepomichene
- Unité d'Entomologie Médicale, Institut Pasteur de Madagascar, Antananarivo 101, Madagascar. Ecole doctorale Sciences de la vie et de l'environnement, Université d'Antananarivo, Antananarivo Madagascar.
| | - Nohal Elissa
- Unité d'Entomologie Médicale, Institut Pasteur de Madagascar, Antananarivo 101, Madagascar
| | - Eric Cardinale
- Centre de coopération Internationale en Recherche Agronomique pour le Développement UMR 15 CMAEE, F-97490 Sainte Clotilde, La Réunion, France Institut National de la Recherche Agronomique (INRA), UMR 1309 CMAEE, F-97490 Sainte Clotilde, La Réunion, France. Centre de Recherche et de Veille sur les maladies émergentes dans l'Océan Indien (CRVOI), plateforme de recherche CYROI, F-97490 Sainte Clotilde, La Réunion, France
| | - Sebastien Boyer
- Unité d'Entomologie Médicale, Institut Pasteur de Madagascar, Antananarivo 101, Madagascar
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Ravagnan S, Montarsi F, Cazzin S, Porcellato E, Russo F, Palei M, Monne I, Savini G, Marangon S, Barzon L, Capelli G. First report outside Eastern Europe of West Nile virus lineage 2 related to the Volgograd 2007 strain, northeastern Italy, 2014. Parasit Vectors 2015; 8:418. [PMID: 26265490 PMCID: PMC4534017 DOI: 10.1186/s13071-015-1031-y] [Citation(s) in RCA: 30] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/08/2015] [Accepted: 08/04/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND West Nile virus (WNV) is a Flavivirus transmitted to vertebrate hosts by mosquitoes, maintained in nature through an enzootic bird-mosquito cycle. In Europe the virus became of major public health and veterinary concern in the 1990s. In Italy, WNV re-emerged in 2008, ten years after the previous outbreak and is currently endemic in many areas of the country. In particular, the northeastern part of Italy experience continuous viral circulation, with human outbreaks caused by different genovariants of WNV lineage 1, Western-European and Mediterranean subcluster, and WNV lineage 2, Hungarian clade. Alongside the WNV National Surveillance Program that has been in place since 2002, regional surveillance plans were implemented after 2008 targeting mosquitoes, animals and humans. FINDINGS In July and September 2014, West Nile virus lineage 2 was detected in pools of Culex pipiens s.l. mosquitoes from northeastern Italy. Whole genome sequencing and phylogenetic analysis of two representative samples identified the presence of WNV lineage 2 related to the Volgograd 2007 strain (99.3 % nucleotide sequence identity), in addition to WNV lineage 2 Hungarian clade. CONCLUSIONS This is the first evidence of the circulation of a WNV lineage 2 strain closely related to the Volgograd 2007 outside Eastern Europe, where it has caused large human outbreaks. This strain may pose a new threat to animal and human health in Italy.
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Affiliation(s)
- Silvia Ravagnan
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
| | - Fabrizio Montarsi
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
| | - Stefania Cazzin
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
| | - Elena Porcellato
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
| | - Francesca Russo
- Promotion and Development of Hygiene and Public Health, Veneto Region, Venezia, Italy.
| | - Manlio Palei
- Veterinary Public Health Service, Friuli Venezia Giulia Region, Udine, Italy.
| | - Isabella Monne
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
| | - Giovanni Savini
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise, Teramo, Italy.
| | - Stefano Marangon
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
| | - Luisa Barzon
- Department of Molecular Medicine, University of Padova, Padova, Italy.
| | - Gioia Capelli
- Istituto Zooprofilattico Sperimentale delle Venezie, Legnaro, Padova, Italy.
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91
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Evaluation of Cross-Protection of a Lineage 1 West Nile Virus Inactivated Vaccine against Natural Infections from a Virulent Lineage 2 Strain in Horses, under Field Conditions. CLINICAL AND VACCINE IMMUNOLOGY : CVI 2015; 22:1040-9. [PMID: 26178384 DOI: 10.1128/cvi.00302-15] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/20/2015] [Accepted: 07/05/2015] [Indexed: 12/27/2022]
Abstract
Although experimental data regarding cross-protection of horse West Nile virus (WNV) vaccines against lineage 2 infections exist, the cross-protective efficacy of these vaccines under field conditions has not been demonstrated. This study was conducted to evaluate the capability of an inactivated lineage 1 vaccine (Equip WNV) to protect against natural infections from the Nea Santa-Greece-2010 lineage 2 strain. In total, 185 WNV-seronegative horses in Thessaloniki, Greece, were selected during 2 consecutive years (2011 and 2012); 140 were immunized, and 45 were used as controls. Horses were examined for signs compatible with WNV infection. Neutralizing antibody titers against the Greek strain and the PaAn001/France lineage 1 strain were determined in immunized horses. WNV circulation was detected during both years in the study area. It was estimated that 37% and 27% of the horses were infected during 2011 and 2012, respectively. Three control animals developed clinical signs, and the WNV diagnosis was confirmed. Signs related to WNV infection were not observed in the vaccinated animals. The nonvaccinated animals had a 7.58% ± 1.82% higher chance of exhibiting signs than immunized animals (P < 0.05). Neutralizing antibodies raised against both strains in all immunized horses were detectable 1 month after the initial vaccination course. The cross-protective capacity of the lowest titer (1:40) was evident in 19 animals which were subsequently infected and did not exhibit signs. Neutralizing antibodies were detectable until the annual booster, when strong anamnestic responses were observed (geometrical mean titer ratio [GMTR] for lineage 1 of 30.2; GMTR for lineage 2 of 27.5). The results indicate that Equip WNV is capable of inducing cross-protection against natural infections from a virulent lineage 2 WNV strain in horses.
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92
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Szentpáli-Gavallér K, Antal L, Tóth M, Kemenesi G, Soltész Z, Dán A, Erdélyi K, Bányai K, Bálint A, Jakab F, Bakonyi T. Monitoring of West Nile virus in mosquitoes between 2011-2012 in Hungary. Vector Borne Zoonotic Dis 2015; 14:648-55. [PMID: 25229703 DOI: 10.1089/vbz.2013.1549] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
West Nile virus (WNV) is a widely distributed mosquito-borne flavivirus. WNV strains are classified into several genetic lineages on the basis of phylogenetic differences. Whereas lineage 1 viruses are distributed worldwide, lineage 2 WNV was first detected outside of Africa in Hungary in 2004. Since then, WNV-associated disease and mortality in animal and human hosts have been documented periodically in Hungary. After the first detection of WNV from a pool of Culex pipiens mosquitoes in 2010, samples were collated from several sources and tested in a 2-year monitoring program. Collection areas were located in the Southern Transdanubium, in northeastern Hungary, in eastern Hungary, and in southeastern Hungary. During the 2 years, 23,193 mosquitoes in 645 pools were screened for WNV virus presence with RT-PCR. Three pools were found positive for WNV in 2011 (one pool of Ochlerotatus annulipes collected in Fényeslitke in June, one pool of Coquillettidia richiardii collected in Debrecen, Fancsika-tó, in July, and one pool of Cx. pipiens captured near Red-Footed Falcon colonies at Kardoskút in September). The minimal infection rate (MIR=proportion of infected mosquitoes per 1000 mosquitoes) of all mosquito pools was 0.25, whereas the MIR of infected species was 2.03 for O. annulipes, 0.63 for C. richiardii, and 2.70 for C.x pipiens. Molecular data have demonstrated that the same lineage 2 WNV strain has circulated in wild birds, horses, humans, and mosquitoes in Hungary since 2004. Mosquito-based surveillance successfully complemented the ongoing, long-term passive surveillance system and it was useful for the early detection of WNV circulation.
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93
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Rizzoli A, Jimenez-Clavero MA, Barzon L, Cordioli P, Figuerola J, Koraka P, Martina B, Moreno A, Nowotny N, Pardigon N, Sanders N, Ulbert S, Tenorio A. The challenge of West Nile virus in Europe: knowledge gaps and research priorities. ACTA ACUST UNITED AC 2015; 20. [PMID: 26027485 DOI: 10.2807/1560-7917.es2015.20.20.21135] [Citation(s) in RCA: 121] [Impact Index Per Article: 13.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
West Nile virus (WNV) is continuously spreading across Europe, and other continents, i.e. North and South America and many other regions of the world. Despite the overall sporadic nature of outbreaks with cases of West Nile neuroinvasive disease (WNND) in Europe, the spillover events have increased and the virus has been introduced into new areas. The high genetic diversity of the virus, with remarkable phenotypic variation, and its endemic circulation in several countries, require an intensification of the integrated and multidisciplinary research efforts built under the 7th Framework Programme of the European Union (FP7). It is important to better clarify several aspects of WNV circulation in Europe, including its ecology, genomic diversity, pathogenicity, transmissibility, diagnosis and control options, under different environmental and socio-economic scenarios. Identifying WNV endemic as well as infection-free areas is becoming a need for the development of human vaccines and therapeutics and the application of blood and organs safety regulations. This review, produced as a joint initiative among European experts and based on analysis of 118 scientific papers published between 2004 and 2014, provides the state of knowledge on WNV and highlights the existing knowledge and research gaps that need to be addressed with high priority in Europe and neighbouring countries.
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Affiliation(s)
- A Rizzoli
- Fondazione Edmund Mach, Research and Innovation Centre, Department of Biodiversity and Molecular Ecology, San Michele all Adige (TN), Italy
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Rizzoli A, Bolzoni L, Chadwick EA, Capelli G, Montarsi F, Grisenti M, de la Puente JM, Muñoz J, Figuerola J, Soriguer R, Anfora G, Di Luca M, Rosà R. Understanding West Nile virus ecology in Europe: Culex pipiens host feeding preference in a hotspot of virus emergence. Parasit Vectors 2015; 8:213. [PMID: 25888754 PMCID: PMC4411713 DOI: 10.1186/s13071-015-0831-4] [Citation(s) in RCA: 75] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2015] [Accepted: 03/28/2015] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Understanding wildlife disease ecology is becoming an urgent need due to the continuous emergence and spread of several wildlife zoonotic diseases. West Nile Virus (WNV) is the most widespread arthropod-borne virus in the world, and in recent decades there has been an increase both in geographic range, and in the frequency of symptomatic infections in humans and wildlife. The principal vector for WNV in Europe is the common house Culex pipiens mosquito, which feeds on a wide variety of vertebrate host species. Variation in mosquito feeding preference has been described as one of the most influential parameters driving intensity and timing of WNV infection in the United States, but feeding preferences for this species have been little studied in Europe. METHODS Here, we estimated feeding preference for wild Cx. pipiens in northern Italy, using molecular analysis to identify the origin of blood meals, and avian census to control host abundance variations. Additionally, we used host bird odour extracts to test experimentally mosquito preferences in the absence of environmental variations. RESULTS For the first time, we demonstrate a clear feeding preference for the common blackbird (Turdus merula), both for wild collected specimens and in the lab, suggesting a potential important role for this species in the WNV epidemiology in Europe. A seasonal decrease in abundance of blackbirds is associated with increased feeding on Eurasian magpies (Pica pica), and this may be linked to seasonal emergence of WNV in humans. Feeding preferences on blackbirds are more marked in rural areas, while preference for magpies is higher in peridomestic areas. Other species, such as the house sparrow (Passer domesticus) appear to be selected by mosquitoes opportunistically in relation to its abundance. CONCLUSIONS Our findings provide new insights into the ecology of Cx. pipiens in Europe and may give useful indications in terms of implementing targeted WNV surveillance plans. However, a clearer understanding of spatio-temporal variations of Cx. pipiens feeding preferences, and targeted studies on reservoir competence for WNV for these species are therefore now urgently needed as this is essential to describe disease dynamics and quantify virus transmission risk.
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Affiliation(s)
- Annapaola Rizzoli
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach. 1, 38010 San Michele all'Adige, Trento, Italy.
| | - Luca Bolzoni
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach. 1, 38010 San Michele all'Adige, Trento, Italy.
- Direzione Sanitaria - Servizio di Analisi del Rischio, Istituto Zooprofilattico Sperimentale della Lombardia e dell'Emilia Romagna, Via dei Mercati 13, 43100, Parma, Italy.
| | - Elizabeth A Chadwick
- Cardiff University, School of Biosciences, Biomedical Science Building, Museum Avenue, Cardiff, CF10 3AX, United Kingdom.
| | - Gioia Capelli
- Laboratory of Parasitology - Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, 35020, Legnaro (Padova), Italy.
| | - Fabrizio Montarsi
- Laboratory of Parasitology - Istituto Zooprofilattico Sperimentale delle Venezie, Viale dell'Università 10, 35020, Legnaro (Padova), Italy.
| | - Michela Grisenti
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach. 1, 38010 San Michele all'Adige, Trento, Italy.
- Department of Veterinary Sciences, University of Torino, Largo Paolo Braccini 2, 10095, Grugliasco, Torino, Italy.
| | - Josue Martínez de la Puente
- Department of Wetland Ecology Estación Biológica Doñana, Consejo Superior de Investigaciones Cientificas, Avda. Americo Vespucio s/n, 41092, Sevilla, Spain.
| | - Joaquin Muñoz
- Department of Wetland Ecology Estación Biológica Doñana, Consejo Superior de Investigaciones Cientificas, Avda. Americo Vespucio s/n, 41092, Sevilla, Spain.
| | - Jordi Figuerola
- Department of Wetland Ecology Estación Biológica Doñana, Consejo Superior de Investigaciones Cientificas, Avda. Americo Vespucio s/n, 41092, Sevilla, Spain.
| | - Ramon Soriguer
- Department of Wetland Ecology Estación Biológica Doñana, Consejo Superior de Investigaciones Cientificas, Avda. Americo Vespucio s/n, 41092, Sevilla, Spain.
| | - Gianfranco Anfora
- Department of Sustainable Ecosystems and Bioresources, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach. 1, 38010 San Michele all'Adige, Trento, Italy.
| | - Marco Di Luca
- Department of Infectious, Parasitic and Immune-Mediated Diseases, Istituto Superiore di Sanità, Viale Regina Elena, 299, 00161, Rome, Italy.
| | - Roberto Rosà
- Department of Biodiversity and Molecular Ecology, Research and Innovation Centre, Fondazione Edmund Mach, Via E. Mach. 1, 38010 San Michele all'Adige, Trento, Italy.
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The global ecology and epidemiology of West Nile virus. BIOMED RESEARCH INTERNATIONAL 2015; 2015:376230. [PMID: 25866777 PMCID: PMC4383390 DOI: 10.1155/2015/376230] [Citation(s) in RCA: 307] [Impact Index Per Article: 34.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/24/2014] [Accepted: 08/10/2014] [Indexed: 12/30/2022]
Abstract
Since its initial isolation in Uganda in 1937 through the present, West Nile virus (WNV) has become an important cause of human and animal disease worldwide. WNV, an enveloped virus of the genus Flavivirus, is naturally maintained in an enzootic cycle between birds and mosquitoes, with occasional epizootic spillover causing disease in humans and horses. The mosquito vectors for WNV are widely distributed worldwide, and the known geographic range of WNV transmission and disease has continued to increase over the past 77 years. While most human infections with WNV are asymptomatic, severe neurological disease may develop resulting in long-term sequelae or death. Surveillance and preventive measures are an ongoing need to reduce the public health impact of WNV in areas with the potential for transmission.
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96
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Bessell PR, Robinson RA, Golding N, Searle KR, Handel IG, Boden LA, Purse BV, Bronsvoort BMDC. Quantifying the Risk of Introduction of West Nile Virus into Great Britain by Migrating Passerine Birds. Transbound Emerg Dis 2014; 63:e347-59. [DOI: 10.1111/tbed.12310] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2014] [Indexed: 11/28/2022]
Affiliation(s)
- P. R. Bessell
- The Roslin Institute; The University of Edinburgh; Easter Bush UK
| | | | | | | | - I. G. Handel
- Royal (Dick) School of Veterinary Studies; The University of Edinburgh; Easter Bush UK
| | - L. A. Boden
- School of Veterinary Medicine; University of Glasgow; Glasgow UK
| | - B. V. Purse
- Centre for Ecology and Hydrology; Wallingford UK
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97
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Hernández-Triana LM, Jeffries CL, Mansfield KL, Carnell G, Fooks AR, Johnson N. Emergence of west nile virus lineage 2 in europe: a review on the introduction and spread of a mosquito-borne disease. Front Public Health 2014; 2:271. [PMID: 25538937 PMCID: PMC4258884 DOI: 10.3389/fpubh.2014.00271] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2014] [Accepted: 11/23/2014] [Indexed: 11/13/2022] Open
Abstract
West Nile virus (WNV) is transmitted by mosquitoes and causes fever and encephalitis in humans, equines, and occasionally wild birds. The virus was first isolated in sub-Saharan Africa where it is endemic. WNV lineage 1 has been responsible for repeated disease outbreaks in the countries of the Mediterranean basin over the past 50 years. This lineage was also introduced into North America in 1999 causing widespread human, equine, and avian mortality. WNV lineage 2, the first WNV lineage to be isolated, was believed to be restricted to sub-Saharan Africa causing a relatively mild fever in humans. However, in 2004, an investigation in Hungary of a case of encephalitis in a wild goshawk (Accipiter gentiles) resulted in the isolation of WNV lineage 2. During the summer of 2004, and in subsequent years, the virus appeared to spread locally throughout Hungary and into neighboring Austria. Subsequently, WNV lineage 2 emerged in Greece in 2010 and in Italy in 2011, involving outbreaks on the Italian mainland and Sardinia. Further spread through the Balkan countries is also suspected. Whole genome sequencing has confirmed that the virus responsible for the outbreaks in Greece and Italy was almost identical to that isolated in Hungary. However, unlike the outbreaks in Hungary, the burden of disease in Mediterranean countries has fallen upon the human population with numerous cases of West Nile fever and a relatively higher mortality rate than in previous outbreaks. The emergence of WNV lineage 2 in Europe, its over-wintering and subsequent spread over large distances illustrates the repeated threat of emerging mosquito-borne diseases. This article will review the emergence of WNV lineage 2 in Europe; consider the pathways for virus spread and the public health implications for the continent.
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Affiliation(s)
- Luis M Hernández-Triana
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
| | - Claire L Jeffries
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
| | - Karen L Mansfield
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
| | - George Carnell
- London School of Hygiene and Tropical Medicine , London , UK
| | - Anthony R Fooks
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK ; Department of Clinical Infection, University of Liverpool , Liverpool , UK
| | - Nicholas Johnson
- Wildlife Zoonoses and Vector-Borne Diseases Research Group, Animal and Plant Health Agency , Addlestone , UK
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98
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Ding XX, Li XF, Deng YQ, Guo YH, Hao W, Che XY, Qin CF, Fu N. Development of a double antibody sandwich ELISA for West Nile virus detection using monoclonal antibodies against non-structural protein 1. PLoS One 2014; 9:e108623. [PMID: 25303282 PMCID: PMC4193763 DOI: 10.1371/journal.pone.0108623] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2014] [Accepted: 08/23/2014] [Indexed: 11/19/2022] Open
Abstract
The early diagnosis of West Nile virus (WNV) infection is important for successful clinical management and epidemiological control. The non-structural protein 1 (NS1) of flavivirus, a highly conserved and secreted glycoprotein, is abundant in the serum of flavivirus-infected patients and represents a useful early diagnostic marker. We developed a WNV-specific NS1 antigen-capture ELISA using two mouse monoclonal antibodies (MAbs) that recognised distinct epitopes of the NS1 protein of WNV as capture and detection antibodies. The antigen-capture ELISA displayed exclusive specificity to WNV without cross-reaction with other related members of the flavivirus family, including the dengue virus, yellow fever virus, Japanese encephalitis virus, and tick-borne encephalitis virus. Additionally, the specificity was presented as no false positive in normal (0/1003) and DENV-infected (0/107) human serum specimens. The detection limit of the antigen-capture ELISA was as low as 15 pg/ml of recombinant WNV NS1 protein (rWNV-NS1) and 6.1 plaque-forming units (PFU)/0.1 ml of WNV-infected culture supernatant. In mice infected with WNV, the NS1 protein was readily detected in serum as early as one day after WNV infection, prior to the development of clinical signs of the disease. The sensitivity of the NS1 capture ELISA (93.7%) was significantly higher (79.4%) than that of real-time reverse transcription polymerase chain reaction in 63 serum samples from WNV-infected mice (p = 0.035). This newly developed NS1 antigen-capture ELISA with high sensitivity and specificity could be used as an efficient method for the early diagnosis of WNV infection in animals or humans.
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Affiliation(s)
- Xi-Xia Ding
- Laboratory of Emerging Infectious Diseases and Division of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Xiao-Feng Li
- Department of Virology, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yong-Qiang Deng
- Department of Virology, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yong-Hui Guo
- Laboratory of Emerging Infectious Diseases and Division of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Wei Hao
- Laboratory of Emerging Infectious Diseases and Division of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Xiao-Yan Che
- Laboratory of Emerging Infectious Diseases and Division of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
| | - Cheng-Feng Qin
- Department of Virology, State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
- * E-mail: (CFQ); (NF)
| | - Ning Fu
- Laboratory of Emerging Infectious Diseases and Division of Laboratory Medicine, Zhujiang Hospital, Southern Medical University, Guangzhou, China
- * E-mail: (CFQ); (NF)
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99
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Di Sabatino D, Bruno R, Sauro F, Danzetta ML, Cito F, Iannetti S, Narcisi V, De Massis F, Calistri P. Epidemiology of West Nile disease in Europe and in the Mediterranean Basin from 2009 to 2013. BIOMED RESEARCH INTERNATIONAL 2014; 2014:907852. [PMID: 25302311 PMCID: PMC4180897 DOI: 10.1155/2014/907852] [Citation(s) in RCA: 44] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/01/2014] [Accepted: 09/02/2014] [Indexed: 01/26/2023]
Abstract
West Nile virus (WNV) transmission has been confirmed in the last four years in Europe and in the Mediterranean Basin. An increasing concern towards West Nile disease (WND) has been observed due to the high number of human and animal cases reported in these areas confirming the importance of this zoonosis. A new epidemiological scenario is currently emerging: although new introductions of the virus from abroad are always possible, confirming the epidemiological role played by migratory birds, the infection endemisation in some European territories today is a reality supported by the constant reoccurrence of the same strains across years in the same geographical areas. Despite the WND reoccurrence in the Old World, the overwintering mechanisms are not well known, and the role of local resident birds or mosquitoes in this context is poorly understood. A recent new epidemiological scenario is the spread of lineage 2 strain across European and Mediterranean countries in regions where lineage 1 strain is still circulating creating favourable conditions for genetic reassortments and emergence of new strains. This paper summarizes the main epidemiological findings on WNV occurrence in Europe and in the Mediterranean Basin from 2009 to 2013, considering potential future spread patterns.
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Affiliation(s)
- Daria Di Sabatino
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Rossana Bruno
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Francesca Sauro
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Maria Luisa Danzetta
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Francesca Cito
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Simona Iannetti
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Valeria Narcisi
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Fabrizio De Massis
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
| | - Paolo Calistri
- Istituto Zooprofilattico Sperimentale dell'Abruzzo e del Molise “G. Caporale,” 64100 Teramo, Italy
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100
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Chaintoutis SC, Dovas CI, Danis K, Gewehr S, Mourelatos S, Hadjichristodoulou C, Papanastassopoulou M. Surveillance and Early Warning of West Nile Virus Lineage 2 Using Backyard Chickens and Correlation to Human Neuroinvasive Cases. Zoonoses Public Health 2014; 62:344-55. [DOI: 10.1111/zph.12152] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2014] [Indexed: 11/30/2022]
Affiliation(s)
- S. C. Chaintoutis
- Laboratory of Microbiology and Infectious Diseases; School of Veterinary Medicine; Faculty of Health Sciences; Aristotle University of Thessaloniki; Thessaloniki Greece
| | - C. I. Dovas
- Laboratory of Microbiology and Infectious Diseases; School of Veterinary Medicine; Faculty of Health Sciences; Aristotle University of Thessaloniki; Thessaloniki Greece
| | - K. Danis
- Department of Surveillance and Intervention; Hellenic Centre for Disease Control and Prevention; Athens Greece
| | - S. Gewehr
- Ecodevelopment S.A. - Environmental Applications; Thessaloniki Greece
| | - S. Mourelatos
- Ecodevelopment S.A. - Environmental Applications; Thessaloniki Greece
| | - C. Hadjichristodoulou
- Department of Hygiene and Epidemiology; School of Medicine; Faculty of Health Sciences; University of Thessaly; Larissa Greece
| | - M. Papanastassopoulou
- Laboratory of Microbiology and Infectious Diseases; School of Veterinary Medicine; Faculty of Health Sciences; Aristotle University of Thessaloniki; Thessaloniki Greece
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