1
|
Lopez K, Harbison J, Irwin P, Erkapic A, Holub R, Blanco C, Paskewitz S, Clifton M, Bartholomay L. Extreme resistance to S-methoprene in field-collected Culex pipiens (Diptera: Culicidae) across the Chicago, IL region. Sci Rep 2024; 14:18001. [PMID: 39097646 PMCID: PMC11297970 DOI: 10.1038/s41598-024-69066-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2024] [Accepted: 07/31/2024] [Indexed: 08/05/2024] Open
Abstract
Insect growth regulators, like S-methoprene, are heavily relied upon worldwide for larval mosquito chemical control due to their target specificity and long-lasting effects. In this study, susceptibility to S-methoprene was evaluated in Culex pipiens, a globally important vector species. Populations from 14 sites throughout the Chicago area with a long history of S-methoprene use and two sites with minimal use in Wisconsin were examined. Using a bioassay methodology and probit analyses, LC50 and LC90 values were calculated and compared to a susceptible laboratory strain to develop resistance ratios, then categorized for resistance intensity. The resistance ratios observed required the addition of another category, termed 'extreme' resistance, indicating resistance ratios greater than 100. 'Low' to 'extreme' levels of resistance to S-methoprene were detected throughout Illinois populations, with resistance ratios ranging from 2.33 to 1010.52. Resistance was not detected in populations where S-methoprene pressure has been very limited. These 'extreme' resistance ratios observed have never been documented in a wild vector species mosquito population. The relationships between historical S-methoprene use, resistance detected with laboratory bioassays, and the potential for field product failure remain unclear. However, the profound resistance detected here demonstrates a potential critical threat to protecting public health from mosquito-borne diseases.
Collapse
Affiliation(s)
- Kristina Lopez
- Department of Entomology, University of Wisconsin-Madison, Madison, WI, USA
- North Shore Mosquito Abatement District, Northfield, IL, USA
| | - Justin Harbison
- North Shore Mosquito Abatement District, Northfield, IL, USA
- Department of Public Health Sciences, Loyola University Chicago, Chicago, IL, USA
| | - Patrick Irwin
- Department of Entomology, University of Wisconsin-Madison, Madison, WI, USA
- Northwest Mosquito Abatement District, Wheeling, IL, USA
| | | | - Robert Holub
- Desplaines Valley Mosquito Abatement District, Lyons, IL, USA
| | | | - Susan Paskewitz
- Department of Entomology, University of Wisconsin-Madison, Madison, WI, USA
| | - Mark Clifton
- North Shore Mosquito Abatement District, Northfield, IL, USA.
| | - Lyric Bartholomay
- Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, WI, USA.
| |
Collapse
|
2
|
Staples K, Neville PJ, Richardson S, Oosthuizen J. Development of a regional climate change model for Aedes vigilax and Aedes camptorhynchus (Diptera: Culicidae) in Perth, Western Australia. BULLETIN OF ENTOMOLOGICAL RESEARCH 2024; 114:8-21. [PMID: 38235528 DOI: 10.1017/s0007485323000561] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2024]
Abstract
Mosquito-borne disease is a significant public health issue and within Australia Ross River virus (RRV) is the most reported. This study combines a mechanistic model of mosquito development for two mosquito vectors; Aedes vigilax and Aedes camptorhynchus, with climate projections from three climate models for two Representative Concentration Pathways (RCPs), to examine the possible effects of climate change and sea-level rise on a temperate tidal saltmarsh habitat in Perth, Western Australia. The projections were run under no accretion and accretion scenarios using a known mosquito habitat as a case study. This improves our understanding of the possible implications of sea-level rise, accretion and climate change for mosquito control programmes for similar habitats across temperate tidal areas found in Southwest Western Australia. The output of the model indicate that the proportion of the year mosquitoes are active increases. Population abundances of the two Aedes species increase markedly. The main drivers of changes in mosquito population abundances are increases in the frequency of inundation of the tidal wetland and size of the area inundated, increased minimum water temperature, and decreased daily temperature fluctuations as water depth increases due to sea level changes, particularly under the model with no accretion. The effects on mosquito populations are more marked for RCP 8.5 when compared to RCP 4.5 but were consistent among the three climate change models. The results indicate that Ae. vigilax is likely to be the most abundant species in 2030 and 2050, but that by 2070 Aedes camptorhynchus may become the more abundant species. This increase would put considerable pressure on existing mosquito control programmes and increase the risk of mosquito-borne disease and nuisance biting to the local community, and planning to mitigate these potential impacts should commence now.
Collapse
Affiliation(s)
- Kerry Staples
- Occupational and Environmental Health, School of Medical and Health Sciences, Edith Cowan University, Joondalup 6027, Australia
| | - Peter J Neville
- Occupational and Environmental Health, School of Medical and Health Sciences, Edith Cowan University, Joondalup 6027, Australia
- Department of Health, Biological and Applied Environmental Health, Environmental Health Directorate, Perth 6849, Western Australia, Australia
| | - Steven Richardson
- Mathematics, School of Science, Edith Cowan University, Joondalup 6027, Australia
| | - Jacques Oosthuizen
- Occupational and Environmental Health, School of Medical and Health Sciences, Edith Cowan University, Joondalup 6027, Australia
| |
Collapse
|
3
|
Palli SR. Juvenile hormone receptor Methoprene tolerant: Functions and applications. VITAMINS AND HORMONES 2023; 123:619-644. [PMID: 37718000 DOI: 10.1016/bs.vh.2023.03.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/19/2023]
Abstract
During the past 15years, after confirming Methoprene tolerant (Met) as a juvenile hormone (JH) receptor, tremendous progress has been made in understanding the function of Met in supporting JH signal transduction. Met role in JH regulation of development, including metamorphosis, reproduction, diapause, cast differentiation, behavior, im`munity, sleep and epigenetic modifications, have been elucidated. Met's Heterodimeric partners involved in performing some of these functions were discovered. The availability of JH response elements (JHRE) and JH receptor allowed the development of screening assays in cell lines and yeast. These screening assays facilitated the identification of new chemicals that function as JH agonists and antagonists. These new chemicals and others that will likely be discovered in the near future by using JH receptor and JHRE will lead to highly effective species-specific environmentally friendly insecticides for controlling pests and disease vectors.
Collapse
Affiliation(s)
- Subba Reddy Palli
- Department of Entomology, College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY, United States.
| |
Collapse
|
4
|
Johnson HE, Clifton M, Harbison JE, Erkapic A, Barrett-Wilt GA, Paskewitz S, Bartholomay L. Assessment of Truck-Mounted Area-Wide S-methoprene Applications to Manage West Nile Virus Vector Species in the Suburbs of Chicago, IL, USA. JOURNAL OF MEDICAL ENTOMOLOGY 2023; 60:384-391. [PMID: 36484651 DOI: 10.1093/jme/tjac170] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/21/2022] [Indexed: 06/17/2023]
Abstract
West Nile virus remains the leading cause of arboviral neuroinvasive disease in the United States, despite extensive efforts to control the mosquito vectors involved in transmission. In this study, we evaluated the effectiveness of Altosid SR-20 (active ingredient, S-methoprene 20%) larvicide applications using truck-mounted ultra-low volume (ULV) dispersal equipment to target Culex pipiens Linnaeus (Diptera: Culicidae) and Cx. restuans (Theobald)larvae. A combination of emergence bioassays, open-field measurements of deposited S-methoprene and spray distribution using gas chromatography-mass spectrometry, and assessments of adult Culex spp. populations in response to applications were conducted over the summer of 2020 within the North Shore Mosquito Abatement District (IL, USA). Open-field applications revealed that dispersed Altosid SR-20 using ULV equipment was effective (75% emergence inhibition in susceptible lab strain Cx. pipiens larvae) up to 53 m. In suburban neighborhood applications, we found that S-methoprene deposition and larval emergence inhibition (EI) in front yards did not differ significantly from backyards. An overall EI of 46% and 28% were observed for laboratory strain Cx. pipiens and wild Cx. restuans larvae respectively, and both had an EI significantly higher than the untreated control group. The EI of exposed wild Cx. pipiens larvae did not differ from the untreated controls, suggesting an increased tolerance to S-methoprene. No difference in abundance of gravid or host-seeking adult Culex spp. post-application was detected between treated and untreated sites. These results document the ability of area-wide application to distribute S-methoprene, but this strategy will need further modifications and evaluation for Culex spp. management.
Collapse
Affiliation(s)
- Haley E Johnson
- Department of Pathobiological Sciences, University of Wisconsin-Madison, 1656 Linden Drive, Madison, WI 53706, USA
| | - Mark Clifton
- North Shore Mosquito Abatement District, 117 Northfield Road, Northfield, IL 60093, USA
| | - Justin E Harbison
- Loyola University Chicago, 2160 South First Avenue, Maywood, IL 60153, USA
| | - Anastazia Erkapic
- North Shore Mosquito Abatement District, 117 Northfield Road, Northfield, IL 60093, USA
| | - Gregory A Barrett-Wilt
- Biotechnology Center, University of Wisconsin-Madison, 425 Henry Mall, Madison, WI 53706, USA
| | - Susan Paskewitz
- Department of Entomology, University of Wisconsin-Madison, 1630 Linden Drive, Madison, WI 53706, USAand
| | - Lyric Bartholomay
- Department of Pathobiological Sciences, University of Wisconsin-Madison, 1656 Linden Drive, Madison, WI 53706, USA
| |
Collapse
|
5
|
Fansiri T, Pongsiri A, Khongtak P, Nitatsukprasert C, Chittham W, Jaichapor B, Pathawong N, Kijchalao U, Tiangtrong S, Singkhaimuk P, Ponlawat A. The impact of insect growth regulators on adult emergence inhibition and the fitness of Aedes aegypti field populations in Thailand. Acta Trop 2022; 236:106695. [PMID: 36122761 DOI: 10.1016/j.actatropica.2022.106695] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2022] [Revised: 09/13/2022] [Accepted: 09/15/2022] [Indexed: 11/01/2022]
Abstract
BACKGROUND The frequent use of insecticides in vector control causes the development of insecticide resistance. Insect growth regulators (IGRs), which effect insect development, are used as a promising alternative to control resistant insect vectors. This study aimed to develop novel effective tools for Aedes aegypti control by evaluating the efficacy of different IGRs on larval development, blood feeding capacity, fecundity, and fertility in females and sperm productivity in males across geographical regions of Thailand. METHODS The efficacy of 16 technical grade IGRs were evaluated against laboratory strain Ae. aegypti larvae in order to determine their emergence inhibition (EI) at 50% and 95% under laboratory conditions. Six IGRs were selected for fecundity, fertility, and sperm productivity studies using feed-through treatments at EI95 concentration levels against adult Ae. aegypti field strains. RESULTS The results from larval bioassay tests indicate that juvenile hormone mimics (EI50 = 0.010-0.229 ppb; EI95 = 0.066-1.118 ppb) and chitin synthesis inhibitors affecting CHS1 (EI50 = 0.240-2.412 ppb; EI95 = 0.444-4.040 ppb) groups effectively inhibited adult Ae. aegypti emergence. Methoprene and fenoxycarb significantly reduced blood feeding capacity. Egg production was comparable among strains while methoprene, pyriproxyfen and diflubenzuron induced egg production. Egg retention was detected in females fed on diflubenzuron. Methoprene, fenoxycarb, diflubenzuron, and teflubenzuron reduced egg hatching rates in mosquito field strains compared to laboratory strain. Male mosquitoes fed on fenoxycarb showed significantly lower sperm production compared to other treatments. CONCLUSION Juvenile hormone analogues and chitin synthesis inhibitors affecting CHS1 groups showed excellent results in adult emergence inhibition in this study. They also disrupted reproductive systems in both adult males and females. This study suggested that they can be used as an alternative larvicide in mosquito control programs.
Collapse
Affiliation(s)
- Thanyalak Fansiri
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Arissara Pongsiri
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Patcharee Khongtak
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Chanyapat Nitatsukprasert
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Wachiraphan Chittham
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Boonsong Jaichapor
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Nattaphol Pathawong
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Udom Kijchalao
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Somsak Tiangtrong
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Preeraya Singkhaimuk
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand
| | - Alongkot Ponlawat
- Vector Biology and Control Section, Department of Entomology, Armed Forces Research Institute of Medical Sciences (AFRIMS), Bangkok 10400, Thailand.
| |
Collapse
|
6
|
Weeks ENI, Kroll KJ, Johnson TS, Colquhoun T, Cuda JP, Denslow ND, Stevens BR. Novel effective mosquito larvicide DL-methionine: Lack of toxicity to non-target aquatic organisms. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2021; 213:112013. [PMID: 33601173 DOI: 10.1016/j.ecoenv.2021.112013] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2020] [Revised: 01/18/2021] [Accepted: 01/28/2021] [Indexed: 06/12/2023]
Abstract
Mosquito larvicides are an effective tool for reducing numbers of adult females that bite and potentially spread pathogenic organisms. Methionine, an essential amino acid in humans, has been previously demonstrated to be a highly effective larvicide against four (4) mosquito species in three (3) genera, Anopheles, Culex and Aedes. The aim of the present study was to determine the potential impact on non-target aquatic organisms of methionine applied as a mosquito larvicide. DL-methionine concentrations ranging from 0.06% to 1.00% were used; wherein the highest concentration of 1.00% would result in 100% mortality within 48 h in mosquitoes. Acute toxicity assays were conducted in accordance with the US Environmental Protection Agency (US EPA) guidelines for the water flea (Daphnia magna Straus; Cladocera: Daphniidae) and the fathead minnow (Pimephales promelas Rafinesque; Cypriniformes: Cyprinidae). Water fleas and fish were placed directly into the solutions in glass containers and tanks for 48-hours and 96-hours, respectively. When applied within the above-mentioned range of effective mosquito larvicide concentrations, DL-methionine meets US EPA criteria as a "practically non-toxic" pesticide for both species. These results suggest that methionine is a viable alternative to current mosquito larvicide options, which are typically classified as moderately to highly toxic and may be a valuable addition to a mosquito integrated pest management program.
Collapse
Affiliation(s)
- Emma N I Weeks
- Entomology and Nematology Department, University of Florida, Gainesville, FL 32611, USA.
| | - Kevin J Kroll
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, USA
| | - Timothy S Johnson
- The Department of Environmental Horticulture, UF/IFAS Plant Innovation Center, University of Florida, Gainesville, FL 32611, USA
| | - Thomas Colquhoun
- The Department of Environmental Horticulture, UF/IFAS Plant Innovation Center, University of Florida, Gainesville, FL 32611, USA
| | - James P Cuda
- Entomology and Nematology Department, University of Florida, Gainesville, FL 32611, USA
| | - Nancy D Denslow
- Department of Physiological Sciences, College of Veterinary Medicine, University of Florida, Gainesville, FL 32611, USA; Department of Biochemistry and Molecular Biology, College of Medicine, University of Florida, Gainesville, FL 32611, USA
| | - Bruce R Stevens
- Department of Physiology and Functional Genomics, University of Florida, Gainesville, FL 32610, USA
| |
Collapse
|
7
|
Su T, Thieme J, Cummings R, Cheng ML, Brown MQ. Cross Resistance in S-Methoprene-Resistant Culex quinquefasciatus (Diptera: Culicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2021; 58:398-402. [PMID: 32914856 DOI: 10.1093/jme/tjaa182] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Indexed: 06/11/2023]
Abstract
The juvenile hormone analog S-methoprene is the only synthetic biopesticide that is registered with the United States Environmental Protection Agency to control arthropods of economic importance in public health, livestock, pets, urban, and stored products. The high activity, relative target specificity, and benign environmental profile of S-methoprene have been well documented. While the risk of resistance in mosquitoes to S-methoprene is generally low, there is a lack of information regarding cross resistance in S-methoprene-resistant mosquitoes to other pesticides. In this paper, a population of the southern house mosquito Culex quinquefasciatus Say from southern California acquired low levels of resistance to S-methoprene in the field, where the resistance ratios ranged 7.0- to 8.8-fold as compared with a laboratory reference colony. After 30 generations of laboratory selections by S-methoprene when resistance was elevated to 57.4- to 168.3-fold relative to an unselected population, various levels of cross resistance to other commonly used pesticides were revealed in the selected population. Cross resistance to the microbial mosquito larvicide Lysinibacillus sphaericus (Meyer & Neide) (Bacillales: Bacillaceae) was the most profound, amounting to 77.50- to 220.50-fold. The mechanism and potential management tactics toward cross resistance are discussed to preserve the unique value of this synthetic biopesticide.
Collapse
Affiliation(s)
- Tianyun Su
- West Valley Mosquito and Vector Control District, Ontario, CA
| | - Jennifer Thieme
- West Valley Mosquito and Vector Control District, Ontario, CA
| | - Robert Cummings
- Orange County Mosquito and Vector Control District, Garden Grove, CA
| | - Min-Lee Cheng
- West Valley Mosquito and Vector Control District, Ontario, CA
| | | |
Collapse
|
8
|
Combining DL-Methionine and Bacillus thuringiensis Subspecies israelensis: Prospects for a Mosquito Larvicide. INSECTS 2020; 11:insects11120880. [PMID: 33322550 PMCID: PMC7764334 DOI: 10.3390/insects11120880] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Revised: 11/25/2020] [Accepted: 12/07/2020] [Indexed: 12/20/2022]
Abstract
Simple Summary With the increasing threat that mosquito borne diseases pose to public health, the demand for environmentally sustainable pesticides has been increasing in recent years. Pesticides that target the larval stage (i.e., larvicides) are particularly useful for controlling mosquito populations as they strike at the source. Currently, Bacillus thuringiensis subspecies israelensis (BTI) is a commonly used mosquito larvicide but some studies show signs of resistance development. DL-methionine is an essential amino acid that has mosquito larvicidal capabilities, while also having minimal negative effects on non-target organisms in laboratory experiments. In this study, our objective was to evaluate the effect of these two larvicides individually and together at reducing mosquito survival. We found that while DL-methionine was more toxic to Anopheles quadrimaculatus than Aedes aegypti, the opposite was true for BTI. Additionally, when the combination was tested against An. quadrimaculatus larvae at higher concentrations the active ingredients were complementary and the effect was equal to both ingredients alone. However, the active ingredients were antagonistic when tested against Ae. aegypti larvae. These findings are important as they show the potential for DL-methionine and the combination of DL-methionine with BTI to be used as a larvicide against Anopheles mosquitoes, which are responsible for transmitting malaria. Abstract Mosquito larvicides can reduce mosquito populations at the source, potentially decreasing biting rates and pathogen transmission. However, there is a growing need for mosquito larvicides that are environmentally sustainable. Bacillus thuringiensis subspecies israelensis (BTI) is a naturally occurring bacterium commonly used as a larvicide to manage mosquito populations. Methionine is an essential amino acid that has demonstrated toxic properties against larval mosquitoes in laboratory experiments, while having minimal effects on non-target organisms. The goal of this study was to evaluate the potential for a novel combination larvicide by testing for compatibility between these two active ingredients. We began by determining the lethal concentration values (LCs) of BTI and DL-methionine against Anopheles quadrimaculatus Say and Aedes aegypti Linnaeus (Diptera: Culicidae) larvae. These bioassays were conducted in glass jars and mortality was observed 48 h post-treatment. We found that while DL-methionine was more toxic to An. quadrimaculatus than Ae. aegypti, the opposite was true for BTI. Then, we used these LCs to conduct bioassays with a combination of BTI and DL-methionine to determine the relationship between the two active ingredients when used against An. quadrimaculatus and Ae. aegypti larvae. The findings of this study demonstrate that BTI and DL-methionine have the potential to be complementary due to their additive properties at higher concentrations and effect levels when tested against An. quadrimaculatus. However, an antagonistic relationship was detected at the concentrations tested with Ae. aegypti. These results are encouraging and imply that a DL-methionine or BTI/DL-methionine combination larvicide could be used in management of Anopheles species.
Collapse
|
9
|
Karungu S, Atoni E, Ogalo J, Mwaliko C, Agwanda B, Yuan Z, Hu X. Mosquitoes of Etiological Concern in Kenya and Possible Control Strategies. INSECTS 2019; 10:E173. [PMID: 31208124 PMCID: PMC6627689 DOI: 10.3390/insects10060173] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/12/2019] [Revised: 06/11/2019] [Accepted: 06/12/2019] [Indexed: 12/21/2022]
Abstract
Kenya is among the most affected tropical countries with pathogen transmitting Culicidae vectors. For decades, insect vectors have contributed to the emergence and distribution of viral and parasitic pathogens. Outbreaks and diseases have a great impact on a country's economy, as resources that would otherwise be used for developmental projects are redirected to curb hospitalization cases and manage outbreaks. Infected invasive mosquito species have been shown to increasingly cross both local and global boarders due to the presence of increased environmental changes, trade, and tourism. In Kenya, there have been several mosquito-borne disease outbreaks such as the recent outbreaks along the coast of Kenya, involving chikungunya and dengue. This certainly calls for the implementation of strategies aimed at strengthening integrated vector management programs. In this review, we look at mosquitoes of public health concern in Kenya, while highlighting the pathogens they have been linked with over the years and across various regions. In addition, the major strategies that have previously been used in mosquito control and what more could be done to reduce or combat the menace caused by these hematophagous vectors are presented.
Collapse
Affiliation(s)
- Samuel Karungu
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Evans Atoni
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Joseph Ogalo
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Caroline Mwaliko
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
- University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Bernard Agwanda
- Mammalogy Section, National Museum of Kenya, P.O. Box 40658, Nairobi 00100, Kenya.
| | - Zhiming Yuan
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
| | - Xiaomin Hu
- Key Laboratory of Special Pathogens and Biosafety, Center for Emerging Infectious Diseases, Wuhan Institute of Virology, Chinese Academy of Sciences, Wuhan 430071, China.
| |
Collapse
|
10
|
Harburguer L, Gonzalez PV, Gonzalez Audino P, Zerba E, Masuh H. N-substituted methyl maleamates as larvicidal compounds against Aedes aegypti (Diptera: Culicidae). Parasitol Res 2017; 117:611-615. [DOI: 10.1007/s00436-017-5729-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2017] [Accepted: 12/20/2017] [Indexed: 10/18/2022]
|
11
|
Lawler SP. Environmental safety review of methoprene and bacterially-derived pesticides commonly used for sustained mosquito control. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2017; 139:335-343. [PMID: 28187397 DOI: 10.1016/j.ecoenv.2016.12.038] [Citation(s) in RCA: 42] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/12/2016] [Revised: 12/23/2016] [Accepted: 12/29/2016] [Indexed: 06/06/2023]
Abstract
Some pesticides are applied directly to aquatic systems to reduce numbers of mosquito larvae (larvicides) and thereby reduce transmission of pathogens that mosquitoes vector to humans and wildlife. Sustained, environmentally-safe control of larval mosquitoes is particularly needed for highly productive waters (e.g., catchment basins, water treatment facilities, septic systems), but also for other habitats to maintain control and reduce inspection costs. Common biorational pesticides include the insect juvenile hormone mimic methoprene and pesticides derived from the bacteria Bacillus thuringiensis israelensis, Lysinibacillus sphaericus and Saccharopolyspora spinosa (spinosad). Health agencies, the public and environmental groups have especially debated the use of methoprene because some studies have shown toxic effects on non-target organisms. However, many studies have demonstrated its apparent environmental safety. This review critically evaluates studies pertinent to the environmental safety of using methoprene to control mosquito larvae, and provides concise assessments of the bacterial larvicides that provide sustained control of mosquitoes. The review first outlines the ecological and health effects of mosquitoes, and distinguishes between laboratory toxicity and environmental effects. The article then interprets non-target toxicity findings in light of measured environmental concentrations of methoprene (as used in mosquito control) and field studies of its non-target effects. The final section evaluates information on newer formulations of bacterially-derived pesticides for sustained mosquito control. Results show that realized environmental concentrations of methoprene were usually 2-5µg/kg (range 2-45µg/kg) and that its motility is limited. These levels were not toxic to the vast majority of vertebrates and invertebrates tested in laboratories, except for a few species of zooplankton, larval stages of some other crustaceans, and small Diptera. Studies in natural habitats have not documented population reductions except in small Diptera. Bacterial larvicides showed good results for sustained control with similarly limited environmental effects, except for spinosad, which had broader effects on insects in mesocosms and temporary pools. These findings should be useful to a variety of stakeholders in informing decisions on larvicide use to protect public and environmental health in a 'One Health' framework.
Collapse
Affiliation(s)
- Sharon P Lawler
- Department of Entomology and Nematology, University of California, Davis One Shields Avenue, Davis, CA 95616, USA.
| |
Collapse
|
12
|
Rust MK, Lance W, Hemsarth H. Synergism of the IGRs Methoprene and Pyriproxyfen Against Larval Cat Fleas (Siphonaptera: Pulicidae). JOURNAL OF MEDICAL ENTOMOLOGY 2016; 53:629-633. [PMID: 26957391 DOI: 10.1093/jme/tjw010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/09/2015] [Accepted: 02/08/2016] [Indexed: 06/05/2023]
Abstract
Insect growth regulators (IGRs) methoprene and pyriproxyfen are widely used as topical treatments to pets or applied to the indoor environment to control cat fleas, Ctenocephalides felis (Bouché). The toxicity of methoprene, pyriproxyfen, and combinations of both IGRs to cat flea larvae was determined. The LC50 of methoprene and pyriproxyfen applied to larval rearing medium was 0.39 and 0.19 ppm, respectively. Combinations of methoprene:pyriproxyfen in ratios of 1:1, 5:1, 10:1, and 20:1 produced LC50s of 0.06, 0.09, 0.19, and 0.13 ppm, respectively. The pyriproxyfen synergized the activity of methoprene as indicated by the combination indices (CI). The ratio of methoprene:pyriproxyfen (40:1) provided an LC50 of 0.42 ppm and the pyriproxyfen was not synergistic. Combinations of pyriproxyfen:methoprene in ratios of 5:1, 10:1, and 20:1 provided LC50s of 0.14, 0.20, 0.20 ppm, respectively, and the methoprene did not synergize the activity of pyriproxyfen. The dose-reduction indices (DRIs) indicated that the concentrations of IGRs in the combinations of methoprene:pyriproxyfen (ratios of 20:1 or less) could be reduced by at least one-third of the amount required by methoprene alone to provide similar larval mortality. Combinations of methoprene and pyriproxyfen may be effective in increasing the residual activity on pets and assist in reducing the likelihood of insecticide resistance developing to IGRs.
Collapse
Affiliation(s)
- Michael K Rust
- Department of Entomology, University of California, Riverside, Riverside, CA 92521-0314 ,
| | | | - H Hemsarth
- The Hartz Mountain Corp., Secaucus, NJ 07094
| |
Collapse
|
13
|
Nishiwaki H, Tabara Y, Kishida T, Nishi K, Shuto Y, Sugahara T, Yamauchi S. Acute larvicidal activity against mosquitoes and oxygen consumption inhibitory activity of dihydroguaiaretic acid derivatives. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2015; 63:2442-2448. [PMID: 25669766 DOI: 10.1021/jf504816a] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
(-)-Dihydroguaiaretic acid (DGA) and its derivatives having 3-hydroxyphenyl (3-OH-DGA) and variously substituted phenyl groups instead of 3-hydroxy-4-methoxyphenyl groups were synthesized to measure their larvicidal activity against the mosquito Culex pipiens Linnaeus, 1758 (Diptera: Culicidae). Compared with DGA and 3-OH-DGA (LC50 (M), 3.52 × 10(-5) and 4.57 × 10(-5), respectively), (8R,8'R)-lignan-3-ol (3) and its 3-Me (10), 2-OH (12), 3-OH (13), and 2-OMe (15) derivatives showed low potency (ca. 6-8 × 10(-5) M). The 4-Me derivative (11) showed the lowest potency (12.1 × 10(-5) M), and the 2-F derivative (4) showed the highest (2.01 × 10(-5) M). All of the synthesized compounds induced an acute toxic symptom against mosquito larvae, with potency varying with the type and position of the substituents. The 4-F derivative (6), which killed larvae almost completely within 45 min, suppressed the O2 consumption of the mitochondrial fraction, demonstrating that this compound inhibited mitochondrial O2 consumption contributing to a respiratory inhibitory activity.
Collapse
Affiliation(s)
- Hisashi Nishiwaki
- Faculty of Agriculture, Ehime University , 3-5-7 Tarumi, Matsuyama, Ehime 790-8566, Japan
| | | | | | | | | | | | | |
Collapse
|
14
|
Kamiabi F, Jaal Z, Keng CL. Bioefficacy of crude extract of Cyperus aromaticus (Family: Cyperaceae) cultured cells, against Aedes aegypti and Aedes albopictus mosquitoes. Asian Pac J Trop Biomed 2013; 3:767-75. [PMID: 24075340 DOI: 10.1016/s2221-1691(13)60153-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2013] [Revised: 07/08/2013] [Accepted: 08/20/2013] [Indexed: 11/24/2022] Open
Abstract
OBJECTIVE To evaluate the growth inhibition activity of the crude extract of Cyperus aromaticus (C. aromaticus) cultured cells against the 3rd instar larvae of Aedes aegypti (Linn.) and Aedes albopictus Skuse (Ae. albopictus) under laboratory conditions, and determine the sublethal effects (EI50) of the crude extract of C. aromaticus cultured cells on some biological and morphological parameters of both Aedes mosquito species during two generations as well. METHODS The cell suspension cultures of C. aromaticus were activated from five callus lines (P4, Pa, Z1, Z6 and Ml) derived from the root explants of in vitro plantlets. The cultured cells were extracted in chloroform and used as plant material for the present study. For detection of juvenile hormone III, the crude extracts were analyzed by HPLC. Then the crude extracts of the three C. aromaticus cultured cell lines which contained varied amounts of juvenile hormone III [high level (P4 cell line), medium level (Z1 cell line) and low level (Ml cell line)] were tested against Aedes mosquito species. Laboratory evaluation was performed against late third instar larvae of the Vector Control Research Unit strains of Ae. aegypti and Ae. albopictus using the standard WHO method. The effects of EI50 of the C. aromaticus cultured P4 cells on fecundity, fertility, growth period, sex ratio, adult size and longevity of Aedes mosquitoes were assessed. RESULTS Bioassay tests presented the remarkable growth inhibition activity of the crude extracts of C. aromaticus cultured cells against the two Aedes mosquitoes. Between the two mosquito species, Ae. albopictus was more susceptible to the crude extracts with lower EI50 values. EI50 of the crude extract of C. aromaticus cultured cells (P4) increased the sterility indices in the parental generation females in both Aedes mosquito species. A significant delay in the pupal formation and adult emergence were observed in the parental generation of the both mosquito species. The sex ratio of the adult population either parental or F1 generation of the Aedes mosquito species was not significantly affected by the EI50 dosage of the crude extract of C. aromaticus cultured P4 cells. A significant decrease in the wing length of the treated adult (female and male) of Aedes aegypti as well as the treated female of Ae. albopictus were observed. Longevity of the adult female of the parental generation of both Aedes mosquitoes as well as females of F1 generation of Ae. albopictus were significantly decreased. CONCLUSIONS The present study revealed the potential of the crude extract of C. aromaticus cultured cells in controlling vector mosquito populations in the effort to reduce the transmission of vector borne diseases.
Collapse
Affiliation(s)
- Fatemeh Kamiabi
- School of Biological Sciences, Universiti Sains Malaysia, Penang, Malaysia; Faculty of Health, Kerman University of Medical Sciences, Kerman, Iran.
| | | | | |
Collapse
|
15
|
Kamita SG, Samra AI, Liu JY, Cornel AJ, Hammock BD. Juvenile hormone (JH) esterase of the mosquito Culex quinquefasciatus is not a target of the JH analog insecticide methoprene. PLoS One 2011; 6:e28392. [PMID: 22174797 PMCID: PMC3235118 DOI: 10.1371/journal.pone.0028392] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2011] [Accepted: 11/07/2011] [Indexed: 11/19/2022] Open
Abstract
Juvenile hormones (JHs) are essential sesquiterpenes that control insect development and reproduction. JH analog (JHA) insecticides such as methoprene are compounds that mimic the structure and/or biological activity of JH. In this study we obtained a full-length cDNA, cqjhe, from the southern house mosquito Culex quinquefasciatus that encodes CqJHE, an esterase that selectively metabolizes JH. Unlike other recombinant esterases that have been identified from dipteran insects, CqJHE hydrolyzed JH with specificity constant (kcat/KM ratio) and Vmax values that are common among JH esterases (JHEs). CqJHE showed picomolar sensitivity to OTFP, a JHE-selective inhibitor, but more than 1000-fold lower sensitivity to DFP, a general esterase inhibitor. To our surprise, CqJHE did not metabolize the isopropyl ester of methoprene even when 25 pmol of methoprene was incubated with an amount of CqJHE that was sufficient to hydrolyze 7,200 pmol of JH to JH acid under the same assay conditions. In competition assays in which both JH and methoprene were available to CqJHE, methoprene did not show any inhibitory effects on the JH hydrolysis rate even when methoprene was present in the assay at a 10-fold higher concentration relative to JH. Our findings indicated that JHE is not a molecular target of methoprene. Our findings also do not support the hypothesis that methoprene functions in part by inhibiting the action of JHE.
Collapse
Affiliation(s)
- Shizuo G. Kamita
- Department of Entomology, University of California Davis, Davis, California, United States of America
- University of California Davis Cancer Center, Sacramento, California, United States of America
| | - Aman I. Samra
- Department of Entomology, University of California Davis, Davis, California, United States of America
- University of California Davis Cancer Center, Sacramento, California, United States of America
| | - Jun-Yan Liu
- Department of Entomology, University of California Davis, Davis, California, United States of America
- University of California Davis Cancer Center, Sacramento, California, United States of America
| | - Anthony J. Cornel
- Department of Entomology, University of California Davis, Davis, California, United States of America
| | - Bruce D. Hammock
- Department of Entomology, University of California Davis, Davis, California, United States of America
- University of California Davis Cancer Center, Sacramento, California, United States of America
- * E-mail:
| |
Collapse
|
16
|
Darabi H, Vatandoost H, Abaei MR, Gharibi O, Pakbaz F. Effectiveness of methoprene, an insect growth regulator, against malaria vectors in Fars, Iran: a field study. Pak J Biol Sci 2011; 14:69-73. [PMID: 21913501 DOI: 10.3923/pjbs.2011.69.73] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Methoprene, an insect growth regulator, was evaluated under field conditions against the main malaria vectors in the Islamic Republic of Iran. The effect of 5, 10 and 20 kg ha(-1) concentration ofmethoprene granule formulation and 100 and 200 mL ha(-1) concentration of EC formulation was measured to determine any changes in Anophelini larval abundance and IE ratio in both rice fields and artificial ponds. In artificial ponds, granular methoprene at a dose of 20 kg ha(-1) inhibited adult emergence by 77.1% after 1 day and 65.9% after 3 days. The emulsifiable concentrate formulation of methoprene at 200 mL ha(-1) inhibited adult emergence by 83.7% after 1 day and 32.2% after 3 days. In rice fields, inhibition of emergence was 44.3% at 20 kg ha(-1) granule and 35.8% for emulsifiable concentrate at 200 mL ha(-1) after 3 days. The results vary depending on the mosquito species, treatment methods, breeding places and type of formulation.
Collapse
Affiliation(s)
- H Darabi
- Public Health Center, Bushehr Medical University of Science, Bushehr, Iran
| | | | | | | | | |
Collapse
|
17
|
Baumann A, Fujiwara Y, Wilson TG. Evolutionary divergence of the paralogs Methoprene tolerant (Met) and germ cell expressed (gce) within the genus Drosophila. JOURNAL OF INSECT PHYSIOLOGY 2010; 56:1445-1455. [PMID: 20457161 DOI: 10.1016/j.jinsphys.2010.05.001] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 04/30/2010] [Accepted: 05/03/2010] [Indexed: 05/29/2023]
Abstract
Juvenile hormone (JH) signaling underpins both regulatory and developmental pathways in insects. However, the JH receptor is poorly understood. Methoprene tolerant (Met) and germ cell expressed (gce) have been implicated in JH signaling in Drosophila. We investigated the evolution of Met and gce across 12 Drosophila species and found that these paralogs are conserved across at least 63 million years of dipteran evolution. Distinct patterns of selection found using estimates of dN/dS ratios across Drosophila Met and gce coding sequences, along with their incongruent temporal expression profiles in embryonic Drosophila melanogaster, illustrate avenues through which these genes have diverged within the Diptera. Additionally, we demonstrate that the annotated gene CG15032 is the 5' terminus of gce. In mosquitoes and beetles, a single Met-like homolog displays structural similarity to both Met and gce, and the intron locations are conserved with those of gce. We found that Tribolium and mosquito Met orthologs are assembled from Met- and gce-specific domains in a modular fashion. Our results suggest that Drosophila Met and gce experienced divergent evolutionary pressures following the duplication of an ancestral gce-like gene found in less derived holometabolous insects.
Collapse
Affiliation(s)
- Aaron Baumann
- Department of Entomology, 400 Aronoff Laboratory, Ohio State University, 318 W. 12th Ave, Columbus, OH 43210, USA
| | | | | |
Collapse
|
18
|
Rivero A, Vézilier J, Weill M, Read AF, Gandon S. Insecticide control of vector-borne diseases: when is insecticide resistance a problem? PLoS Pathog 2010; 6:e1001000. [PMID: 20700451 PMCID: PMC2916878 DOI: 10.1371/journal.ppat.1001000] [Citation(s) in RCA: 233] [Impact Index Per Article: 16.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Many of the most dangerous human diseases are transmitted by insect vectors. After decades of repeated insecticide use, all of these vector species have demonstrated the capacity to evolve resistance to insecticides. Insecticide resistance is generally considered to undermine control of vector-transmitted diseases because it increases the number of vectors that survive the insecticide treatment. Disease control failure, however, need not follow from vector control failure. Here, we review evidence that insecticide resistance may have an impact on the quality of vectors and, specifically, on three key determinants of parasite transmission: vector longevity, competence, and behaviour. We argue that, in some instances, insecticide resistance is likely to result in a decrease in vector longevity, a decrease in infectiousness, or in a change in behaviour, all of which will reduce the vectorial capacity of the insect. If this effect is sufficiently large, the impact of insecticide resistance on disease management may not be as detrimental as previously thought. In other instances, however, insecticide resistance may have the opposite effect, increasing the insect's vectorial capacity, which may lead to a dramatic increase in the transmission of the disease and even to a higher prevalence than in the absence of insecticides. Either way-and there may be no simple generality-the consequence of the evolution of insecticide resistance for disease ecology deserves additional attention.
Collapse
Affiliation(s)
- Ana Rivero
- Génétique et Evolution des Maladies Infectieuses (UMR CNRS 2724), Centre de Recherche IRD, Montpellier, France.
| | | | | | | | | |
Collapse
|
19
|
Vasquez MI, Violaris M, Hadjivassilis A, Wirth MC. Susceptibility of Culex pipiens (Diptera: Culicidae) field populations in Cyprus to conventional organic insecticides, Bacillus thuringiensis subsp. israelensis, and methoprene. JOURNAL OF MEDICAL ENTOMOLOGY 2009; 46:881-887. [PMID: 19645293 DOI: 10.1603/033.046.0421] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/28/2023]
Abstract
Culex pipiens pipiens L. populations on Cyprus were sampled over a 6-yr period from 2002 to 2008 to evaluate the status of insecticide resistance toward the insecticides temephos, chlorpyrifos, and permethrin and to study susceptibility levels toward the recently introduced bacterial insecticide Bacillus thuringiensis subsp. israelensis De Barjac and the juvenile hormone analog, methoprene. Susceptibility to the three conventional chemical insecticides varied between different collections, with most collections showing moderate or low resistance. The 2004 Akrotiri collection had the highest temephos resistance ratio, 167-fold at the LC95, although later sampling showed that the population returned to susceptibility after treatments stopped. Chlorpyrifos resistance was generally higher than temephos resistance. Four collections showed high resistance, and the resistance ratios of two collections were notably high with resistance ratios of 110- and 248-fold at the LC95. Three collections showed high permethrin resistance (22.5-, 23.9-, and 86.3-fold). The frequency of elevated esterase activity in populations was estimated using a filter paper test, and frequencies varied from 0.9 to 65% among collections. The levels of temephos resistance and the frequency of elevated esterases in this survey were generally lower than in earlier reports, suggesting a decline in temephos resistance. Dose-response values for B. thuringiensis subsp. israelensis covered an approximate eight-fold range, but no resistance was detected. Methoprene values showed a 4.7-fold and 16-fold range at the LC50 and LC95, respectively. Two populations showed significant resistance ratios at the LC95. These data are discussed in relation to the changes in larval control practices underway in Cyprus.
Collapse
Affiliation(s)
- Marlen I Vasquez
- Medical Entomology Laboratory, Medical and Public Health Services, Ministry of Health, 19 Campou St., Strovolos, CY 2030 Nicosia, Cyprus.
| | | | | | | |
Collapse
|
20
|
Spafford H, Jardine A, Carver S, Tarala K, Van Wees M, Weinstein P. Laboratory determination of efficacy of a Santalum spicatum extract for mosquito control. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2007; 23:304-311. [PMID: 17939511 DOI: 10.2987/8756-971x(2007)23[304:ldoeoa]2.0.co;2] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
The activity of QN50, a sequiterpene alcohol derived from Australian sandalwood (Santalum spicatum), was tested for its effectiveness against larvae of 2 mosquito species (Culex molestus and Aedes camptorhynchus [Diptera: Culicidael), nymphs of 2 species of water boatmen (Micronecta robusta and Agraptocorixa [Hemiptera: Corixidae]), immature Daphnia sp. (Crustacea), and mosquito eggs (Cx. molestus). In a series of laboratory bioassays, field-collected mosquito larvae, eggs, and immature corixids and daphnids were placed in beakers with either QN50, methoprene or source water only (control). The mosquito larvae exposed to QN50 had reduced survivorship and average longevity relative to the control and to methoprene at most concentrations used in this study. The hatching rate of mosquito eggs was unaffected by methoprene or QN50. Corixid nymphs and daphnids experienced high mortality in both methoprene and QN50 relative to the control, but there was no difference in the effect between the compounds. The results of this preliminary study suggest that further research into the mode of action and efficacy of QN50 as a potential alternative to methoprene for mosquito abatement is warranted.
Collapse
Affiliation(s)
- Helen Spafford
- School of Animal Biology (M085), University of Western Australia, 35 Stirling Highway, Crawley, Western Australia
| | | | | | | | | | | |
Collapse
|
21
|
Wang S, Baumann A, Wilson TG. Drosophila melanogaster Methoprene-tolerant (Met) gene homologs from three mosquito species: Members of PAS transcriptional factor family. JOURNAL OF INSECT PHYSIOLOGY 2007; 53:246-53. [PMID: 17166512 PMCID: PMC1904834 DOI: 10.1016/j.jinsphys.2006.07.011] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2006] [Revised: 06/30/2006] [Accepted: 07/03/2006] [Indexed: 05/09/2023]
Abstract
The Methoprene-tolerant (Met) gene in Drosophila melanogaster has been shown to function in juvenile hormone (JH) action. Met homologs were isolated from three mosquito species, Culex pipiens, Aedes aegypti and Anopheles gambiae. Sequence similarity was found to be high in bHLH and PAS conserved domains, and the majority of the 7-9 introns in AaMet and AgMet are located in either identical or similar positions, indicating evolutionary relatedness. Sequence comparison with Met and the similar germ-cell expressed (gce) gene in D. melanogaster showed that the mosquito genes are more similar to gce than to Met. Moreover, the multiple introns in AgMet and AaMet are more similar in number with the 7 introns in Dmgce than to the single intron in DmMet; in fact, six intron positions in AaMet and AgMet are similar to those in Dmgce. Efforts to identify a second homologous gene in mosquitoes were unsuccessful, suggesting a single gene in lower Diptera, consistent with the single gene uncovered in genomic sequencing of Ae. aegypti and An. gambiae. These results suggest that a gene duplication occurred during the evolution of higher Diptera, resulting in Met and gce.
Collapse
Affiliation(s)
| | | | - Thomas G. Wilson
- *: Author for correspondence. E-mail: , Phone: 614-247-6036, Fax: 614-292-2180
| |
Collapse
|
22
|
Soin T, Smagghe G. Endocrine disruption in aquatic insects: a review. ECOTOXICOLOGY (LONDON, ENGLAND) 2007; 16:83-93. [PMID: 17235670 DOI: 10.1007/s10646-006-0118-9] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
There is mounting evidence that a wide variety of compounds can have endocrine disrupting effects on humans and wildlife. However, investigations so far have focused primarily on exposure to human and other vertebrates, with invertebrate findings largely restricted to marine mollusks or to the ecdysteroid and juvenile hormone agonists as purposely synthesized endocrine disrupters for the pest management of insects. This article provides a brief description of the insect hormone system, a short sum-up of the relevant insect groups with aquatic life stages, and an overview of the additional evidence for endocrine disruption in aquatic insects from laboratory and field studies since 1999. In addition, the suitability of insects as sentinels for endocrine disrupting chemicals in aquatic ecosystems is discussed. Conclusions are drawn and research needs are defined.
Collapse
Affiliation(s)
- Thomas Soin
- Laboratory of Agrozoology, Department of Crop Protection, Faculty of Bioscience Engineering, Ghent University, Coupure links 653, B-9000, Ghent, Belgium.
| | | |
Collapse
|
23
|
Floore TG. Mosquito larval control practices: past and present. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2006; 22:527-33. [PMID: 17067057 DOI: 10.2987/8756-971x(2006)22[527:mlcppa]2.0.co;2] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
Pestiferous mosquito problems and control solutions were reported as early as ancient Greek literature. In the 19th century, it was discovered that these same mosquitoes carried diseases (malaria, dengue) that had until then been attributed to "dirty" water and swamp gases. Until relatively recently, in both urban and rural areas in the United States, the lack of effective mosquito control often drove humans and animals indoors or into nearby rivers to escape the hordes of blood-sucking mosquitoes. Early mosquito control methods included source reduction, mosquito-eating fish, and chemicals. These methodologies continue today, in a much more sophisticated manner, but following the principles first laid down by early 20th century medical entomologists such as L. O. Howard. This article explores mosquito larval control practices from the 1900s to the present.
Collapse
Affiliation(s)
- Thomas G Floore
- John A Mulrennan, Sr Public Health Entomology Research and Education Center, College of Engineering Sciences, Technology, and Agriculture, Florida Agriculture and Mechanical University, Panama City 32405-1933, USA
| |
Collapse
|
24
|
Kawada H, Saita S, Shimabukuro K, Hirano M, Koga M, Iwashita T, Takagi M. Mosquito larvicidal effectiveness of EcoBio-Block S: a novel integrated water-purifying concrete block formulation containing insect growth regulator pyriproxyfen. JOURNAL OF THE AMERICAN MOSQUITO CONTROL ASSOCIATION 2006; 22:451-6. [PMID: 17067045 DOI: 10.2987/8756-971x(2006)22[451:mleoes]2.0.co;2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
EcoBio-Block S, a novel controlled release system (CRS) for the insect growth regulator pyriproxyfen, uses a water-purifying concrete block system (EcoBio-Block) composed of a porous volcanic rock and cement, and it incorporates the aerobic bacterial groups of Bacillus subtilis natto. EcoBio-Block S showed high inhibitory activity against mosquito emergence as well as a water-purifying effect. Chemical analysis and bioassay showed that EcoBio-Block S provides a high-performance CRS that controls the release of pyriproxyfen at low levels according to "zero order kinetics".
Collapse
Affiliation(s)
- Hitoshi Kawada
- Department of Vector Ecology and Environment, Institute of Tropical Medicine, Nagasaki University, Japan
| | | | | | | | | | | | | |
Collapse
|
25
|
Wilson TG, Wang S, Beno M, Farkas R. Wide mutational spectrum of a gene involved in hormone action and insecticide resistance in Drosophila melanogaster. Mol Genet Genomics 2006; 276:294-303. [PMID: 16802158 DOI: 10.1007/s00438-006-0138-4] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2006] [Accepted: 05/23/2006] [Indexed: 11/27/2022]
Abstract
The Methoprene-tolerant (Met) bHLH-PAS gene in Drosophila melanogaster is involved in the molecular action of juvenile hormone (JH), and mutants result in resistance to the toxic and morphogenetic effects of JH and JH agonist insecticides such as methoprene. A detailed study of Met mutants can shed light on the poorly understood action of JH as well as the molecular basis of Met resistance to JH insecticides. Nine mutant alleles bearing point mutations in Met were examined for penetrance and expressivity of three phenotypic characters: resistance, defective oogenesis, and a novel eye defect. The collection ranged from two weak alleles having less severe phenotypes to strong alleles with severe phenotypes similar to that of a null allele. The point mutations were located in both conserved and nonconserved domains. Both the eye defect, seen as severely malformed ommatidial facets in the posterior margin of the compound eye, and the oogenesis phenotype are nonconditional, whereas expression of the resistance phenotype requires treatment with JH or JH analogs (JHAs) during early metamorphosis. A proposed basis for all the phenotypic characters centers on MET action as a transcriptional regulator of ecdysone secondary-response target genes during metamorphosis. Disruption of MET function either by mutation or by JHA presence during early metamorphosis results in transcriptional misregulation of different target genes, resulting in the pathology seen in either instance. The variety of amino acid changes in MET that resulted in resistance may portend a rapid rise in resistance in response to increased use of JH insecticides in field insect populations.
Collapse
Affiliation(s)
- Thomas G Wilson
- Department of Entomology, Ohio State University, Columbus, OH 43210, USA.
| | | | | | | |
Collapse
|
26
|
Aronov PA, Dettmer K, Christiansen JA, Cornel AJ, Hammock BD. Development of a HPLC/tandem-MS method for the analysis of the larvicides methoprene, hydroprene, and kinoprene at trace levels using Diels-Alder derivatization. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2005; 53:3306-12. [PMID: 15853364 PMCID: PMC1479544 DOI: 10.1021/jf0485842] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The invasion and subsequent spread of the mosquito-borne West Nile virus in the United States has resulted in increased use of methoprene. With the increased need for sensitive detection and monitoring of methoprene in the environment, an analytical LC/ESI-MS/MS method has been developed for the analysis of methoprene and two analogues, kinoprene and hydroprene, in water. To improve the ionization efficiency of the nonpolar analytes, a derivatization step with the Cookson-type reagent 4-phenyl-1,2,4-triazoline-3,5-dione (PTAD) was used. Derivatization improved the limit of detection 100-fold. For tandem MS analyses, limits of detection in environmental water samples (S/N = 3) are about 6 pg/mL for methoprene and 20 pg/mL for kinoprene and hydroprene, resulting in limits of quantification (S/N = 10) of 20 pg/mL for methoprene and 60 pg/mL for hydroprene and kinoprene extracted from 10 mL of water. This method was applied to measure methoprene concentrations in water samples from a treated site.
Collapse
Affiliation(s)
- Pavel A Aronov
- Department of Entomology, University of California at Davis, California 95616, USA
| | | | | | | | | |
Collapse
|
27
|
Beckage NE, Marion KM, Walton WE, Wirth MC, Tan FF. Comparative larvicidal toxicities of three ecdysone agonists on the mosquitoes Aedes aegypti, Culex quinquefasciatus, and Anopheles gambiae. ARCHIVES OF INSECT BIOCHEMISTRY AND PHYSIOLOGY 2004; 57:111-122. [PMID: 15484259 DOI: 10.1002/arch.20021] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Ecdysone agonists are hormonally active insect growth regulators that disrupt development of pest insects and have potential for development as insecticides. Their effects have been particularly well-studied in Lepidoptera and Coleoptera, but significantly less is known about their effects on dipterans, particularly aquatic species. The potency of three ecdysone agonists on larvae of 3 mosquito species, Aedes aegypti, Anopheles gambiae, and Culex quinquefasciatus, was examined. Anopheles gambiae was the most susceptible species and Ae. aegypti was the most resistant species to the effects of the three compounds tested. Potency, in descending order, was RH-2485 > RH-5992 > RH-5849. Dose-response relationships were determined for the three agonists; RH-2485 was found to be the most effective endocrine disruptor against all three species. The observed biological effects of these compounds were similar to those reported for other insects, and mosquitoes initiated molting and apolysis but did not complete a molt. In some cases, mosquito larvae synthesized a new cuticle that appeared to be normally sclerotized but the larvae failed to ecdyse and shed the exuvium. These compounds may prove to be valuable insect growth regulators for control of mosquitoes to decrease the frequency of pathogen transmission to humans. Prospects for using these compounds to control mosquitoes in the field are discussed, along with possible impacts on non-target arthropods in mosquito habitats.
Collapse
Affiliation(s)
- Nancy E Beckage
- Department of Entomology, University of California, Riverside, CA 92521, USA.
| | | | | | | | | |
Collapse
|
28
|
Kristensen M, Jespersen JB. Larvicide resistance in Musca domestica (Diptera: Muscidae) populations in Denmark and establishment of resistant laboratory strains. JOURNAL OF ECONOMIC ENTOMOLOGY 2003; 96:1300-1306. [PMID: 14503604 DOI: 10.1603/0022-0493-96.4.1300] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
We determined the toxicity of the two IGRs, diflubenzuron and cyromazine, in this survey of resistance in Danish field populations of Musca domestica (L.). We observed resistance toward diflubenzuron and for the first time in Denmark and we found field populations with some resistance to cyromazine. Eleven of the twenty-one field populations had larvae surviving a diagnostic dose of 1.6 times of susceptible LC95 of diflubenzuron and two of these populations had larvae surviving 6.1 times of LC95. Eight of the twenty-one field populations had larvae surviving 2.2 times of susceptible LC95 of cyromazine and one population had larvae surviving 4.4 times of LC95. A fivefold cyromazine resistant strain was established after selection with cyromazine. It was 3-, 5-, and 90-fold resistant to diflubenzuron, triflumuron, and methoprene, respectively. Two diflubenzuron resistant strains (120- and 86-fold, respectively) were established. They showed a high level of resistance to triflumuron (1000- and 200-fold, respectively), and moderate resistance to methoprene (73- and 50-fold, respectively). Both were susceptible to cyromazine. This study shows that by applying the recommendations of previous resistance risk assessments, severe control failures and detrimental development of a high level of resistance have been avoided. The development of resistance has not been completely avoided, but has not developed to a level of biological or economic importance.
Collapse
Affiliation(s)
- Michael Kristensen
- Danish Pest Infestation Laboratory, Skovbrynet 14, DK-2800 Kgs, Lyngby, Denmark.
| | | |
Collapse
|