The Experts below are selected from a list of 33 Experts worldwide ranked by ideXlab platform
Robert K. Washino - One of the best experts on this subject based on the ideXlab platform.
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Comparison of recapture patterns of marked and released Aedes vexans and Ae. melanimon (Diptera: Culicidae) in the Sacramento Valley of California.
Journal of medical entomology, 1994Co-Authors: Truls Jensen, Robert K. WashinoAbstract:Recapture patterns of Aedes vexans (Meigen) and Aedes melanimon Dyar were compared in a mark-release-recapture study conducted on the Colusa National Wildlife Refuge, Colusa County, California, from 15 August to 2 September 1988. The 2.0% recapture rate for Ae. vexans females was significantly greater than the 0.9% rate for Ae. melanimon females. Daily survivorship of 0.70 for Ae. vexans females was significantly lower than the 0.84 estimate for Ae. melanimon. The two species had different patterns of dispersal. On day 1, when the majority of marked females of both species were recaptured, the mean dispersal distance for Ae. vexans females was significantly greater than that for Ae. melanimon. The cumulative dispersal distance for Ae. vexans females decreased over the study period. In contrast, Ae. melanimon dispersal distances increased gradually over time.
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An assessment of the biological capacity of a Sacramento Valley population of Aedes melanimon to vector arboviruses.
The American journal of tropical medicine and hygiene, 1991Co-Authors: Truls Jensen, Robert K. WashinoAbstract:Abstract Daily survivorship, duration of the gonotrophic cycle, absolute abundance and season-long relative abundance were estimated for Aedes melanimon in the Sacramento Valley of California in 1987 and 1988 using mark-release-recapture (MRR) techniques and by monitoring changes in the abundance and parity rate of the native population. One objective of these studies was to determine the extent to which A. melanimon was biologically capable of serving as a horizontal arbovirus vector. Daily survivorship was estimated to be 0.90 and 0.84 in MRR studies conducted in September 1987 and August 1988, 0.89 based on changes in the parity state and abundance of the native population in August 1988 and 0.82 using summer-long parity data in 1988. Gonotrophic cycle length (GCL) was estimated to be five days in three studies. Aedes melanimon densities were estimated to be approximately 1,000,000 and 15,000 females per hectare in September 1987 and August 1988 respectively. Parous A. melanimon females were collected on each sampling occasion from April to November 1988, suggesting that A. melanimon maintained a continuous presence in the study area throughout the summer. The results of these studies suggest that A. melanimon has the potential to be an efficient horizontal vector of western equine encephalomyelitis (WEE), based on high adult survivorship, short GCL, high abundance and a continuous presence across the summer. This supports the concept of a WEE transmission cycle in the Sacramento Valley involving Ae. melanimon as an important vector. Aedes melanimon also can be an efficient horizontal vector of California encephalitis virus (CE), though the importance of horizontal transmission to the maintenance of CE virus is unclear.
Andrea L. Joyce - One of the best experts on this subject based on the ideXlab platform.
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Wolbachia in mosquitoes from the Central Valley of California, USA
Parasites & Vectors, 2020Co-Authors: Ryan Torres, Eunis Hernandez, Valeria Flores, Jose Luis Ramirez, Andrea L. JoyceAbstract:Background Wolbachia bacteria are widely distributed throughout terrestrial arthropod species. These bacteria can manipulate reproduction and influence the vector competence of their hosts. Recently, Wolbachia have been integrated into vector control programmes for mosquito management. A number of supergroups and strains exist for Wolbachia , and they have yet to be characterized for many mosquito species. In this study, we examined Wolbachia prevalence and their phylogenetic relationship to other Wolbachia , using mosquitoes collected in Merced County in the Central Valley of California. Methods Adult mosquitoes were collected from 85 sites in Merced County, California in 2017 and 2018. Traditional and quantitative PCR were used to investigate the presence or absence and the density of Wolbachia , using Wolbachia -specific 16S rRNA and Wolbachia- surface protein ( wsp ) genes. The supergroup of Wolbachia was determined, and Multilocus Sequence Typing (MLST) by sequencing five housekeeping genes ( cox A, gat B, fts Z, hcp A and fbp A) was also used to determine Wolbachia supergroup as well as strain. Results Over 7100 mosquitoes of 12 species were collected: Aedes melanimon , Ae . nigromaculis , Ae . vexans , Ae . aegypti , Culex pipiens , Cx . stigmatosoma , Cx . tarsalis , Anopheles franciscanus , An . freeborni , An . punctipennis , Culiseta incidens and Cs . inornata . Eight showed evidence of Wolbachia . To our knowledge, this study is the first to report detection of Wolbachia in five of these species ( Ae . melanimon , Cx . stigmatosoma , Cx . tarsalis , Cs . incidens and Cs . inornata ). Culex pipiens and Cx . stigmatosoma had a high frequency and density of Wolbachia infection, which grouped into supergroup B; Cs . inornata clustered with supergroup A. MLST comparisons identified Cx . pipiens and Cx . stigmatosoma as w Pip strain type 9 supergroup B. Six species had moderate to low (< 14%) frequencies of Wolbachia . Four species were negative, Ae . nigromaculis , An . franciscanus , An . freeborni and Ae . aegypti . Conclusions New records of Wolbachia detection were found in mosquitoes from Merced County, California. Culex stigmatosoma and Cs . inornata were new records for Wolbachia supergroup B and A, respectively. Other species with Wolbachia occurred with low frequency and low density. Detection of Wolbachia in mosquitoes can be used to inform potential vector control applications. Future study of Wolbachia within Cx . stigmatosoma and Cs . inornata in California and through the range of these species could further explore Wolbachia infection in these two species.
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Wolbachia in mosquitoes from the Central Valley of California, USA
Parasites & vectors, 2020Co-Authors: Ryan Torres, Eunis Hernandez, Valeria Flores, Jose Luis Ramirez, Andrea L. JoyceAbstract:Author(s): Torres, Ryan; Hernandez, Eunis; Flores, Valeria; Ramirez, Jose Luis; Joyce, Andrea L | Abstract: BackgroundWolbachia bacteria are widely distributed throughout terrestrial arthropod species. These bacteria can manipulate reproduction and influence the vector competence of their hosts. Recently, Wolbachia have been integrated into vector control programmes for mosquito management. A number of supergroups and strains exist for Wolbachia, and they have yet to be characterized for many mosquito species. In this study, we examined Wolbachia prevalence and their phylogenetic relationship to other Wolbachia, using mosquitoes collected in Merced County in the Central Valley of California.MethodsAdult mosquitoes were collected from 85 sites in Merced County, California in 2017 and 2018. Traditional and quantitative PCR were used to investigate the presence or absence and the density of Wolbachia, using Wolbachia-specific 16S rRNA and Wolbachia-surface protein (wsp) genes. The supergroup of Wolbachia was determined, and Multilocus Sequence Typing (MLST) by sequencing five housekeeping genes (coxA, gatB, ftsZ, hcpA and fbpA) was also used to determine Wolbachia supergroup as well as strain.ResultsOver 7100 mosquitoes of 12 species were collected: Aedes melanimon, Ae. nigromaculis, Ae. vexans, Ae. aegypti, Culex pipiens, Cx. stigmatosoma, Cx. tarsalis, Anopheles franciscanus, An. freeborni, An. punctipennis, Culiseta incidens and Cs. inornata. Eight showed evidence of Wolbachia. To our knowledge, this study is the first to report detection of Wolbachia in five of these species (Ae. melanimon, Cx. stigmatosoma, Cx. tarsalis, Cs. incidens and Cs. inornata). Culex pipiens and Cx. stigmatosoma had a high frequency and density of Wolbachia infection, which grouped into supergroup B; Cs. inornata clustered with supergroup A. MLST comparisons identified Cx. pipiens and Cx. stigmatosoma as wPip strain type 9 supergroup B. Six species had moderate to low (l 14%) frequencies of Wolbachia. Four species were negative, Ae. nigromaculis, An. franciscanus, An. freeborni and Ae. aegypti.ConclusionsNew records of Wolbachia detection were found in mosquitoes from Merced County, California. Culex stigmatosoma and Cs. inornata were new records for Wolbachia supergroup B and A, respectively. Other species with Wolbachia occurred with low frequency and low density. Detection of Wolbachia in mosquitoes can be used to inform potential vector control applications. Future study of Wolbachia within Cx. stigmatosoma and Cs. inornata in California and through the range of these species could further explore Wolbachia infection in these two species.
Truls Jensen - One of the best experts on this subject based on the ideXlab platform.
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Comparison of recapture patterns of marked and released Aedes vexans and Ae. melanimon (Diptera: Culicidae) in the Sacramento Valley of California.
Journal of medical entomology, 1994Co-Authors: Truls Jensen, Robert K. WashinoAbstract:Recapture patterns of Aedes vexans (Meigen) and Aedes melanimon Dyar were compared in a mark-release-recapture study conducted on the Colusa National Wildlife Refuge, Colusa County, California, from 15 August to 2 September 1988. The 2.0% recapture rate for Ae. vexans females was significantly greater than the 0.9% rate for Ae. melanimon females. Daily survivorship of 0.70 for Ae. vexans females was significantly lower than the 0.84 estimate for Ae. melanimon. The two species had different patterns of dispersal. On day 1, when the majority of marked females of both species were recaptured, the mean dispersal distance for Ae. vexans females was significantly greater than that for Ae. melanimon. The cumulative dispersal distance for Ae. vexans females decreased over the study period. In contrast, Ae. melanimon dispersal distances increased gradually over time.
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An assessment of the biological capacity of a Sacramento Valley population of Aedes melanimon to vector arboviruses.
The American journal of tropical medicine and hygiene, 1991Co-Authors: Truls Jensen, Robert K. WashinoAbstract:Abstract Daily survivorship, duration of the gonotrophic cycle, absolute abundance and season-long relative abundance were estimated for Aedes melanimon in the Sacramento Valley of California in 1987 and 1988 using mark-release-recapture (MRR) techniques and by monitoring changes in the abundance and parity rate of the native population. One objective of these studies was to determine the extent to which A. melanimon was biologically capable of serving as a horizontal arbovirus vector. Daily survivorship was estimated to be 0.90 and 0.84 in MRR studies conducted in September 1987 and August 1988, 0.89 based on changes in the parity state and abundance of the native population in August 1988 and 0.82 using summer-long parity data in 1988. Gonotrophic cycle length (GCL) was estimated to be five days in three studies. Aedes melanimon densities were estimated to be approximately 1,000,000 and 15,000 females per hectare in September 1987 and August 1988 respectively. Parous A. melanimon females were collected on each sampling occasion from April to November 1988, suggesting that A. melanimon maintained a continuous presence in the study area throughout the summer. The results of these studies suggest that A. melanimon has the potential to be an efficient horizontal vector of western equine encephalomyelitis (WEE), based on high adult survivorship, short GCL, high abundance and a continuous presence across the summer. This supports the concept of a WEE transmission cycle in the Sacramento Valley involving Ae. melanimon as an important vector. Aedes melanimon also can be an efficient horizontal vector of California encephalitis virus (CE), though the importance of horizontal transmission to the maintenance of CE virus is unclear.
William C. Reeves - One of the best experts on this subject based on the ideXlab platform.
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Mouse and baby chicken virulence of enzootic strains of western equine encephalomyelitis virus from California.
The American journal of tropical medicine and hygiene, 1997Co-Authors: James L. Hardy, S. B. Presser, Robert E. Chiles, William C. ReevesAbstract:Abstract Eight enzootic strains of western equine encephalomyelitis (WEE) virus isolated from Culex tarsalis or Aedes melanimon collected in several geographic areas of California were evaluated for their virulence in suckling mice, adult mice, and one-day-old baby chickens. The epidemic Fleming strain and the cloned B628(Cl 15) variant were used as virulent and avirulent control viruses, respectively, in adult mice. Enzootic strains of WEE virus were grouped into three phenotypes on the basis of their neurovirulent and neuroinvasive properties in adult mice. Three strains possessed high neurovirulence and were neuroinvasive; three strains had intermediate neurovirulence and lacked neuroinvasiveness; and two strains had low to nil neurovirulence and were non-neuroinvasive. In fact, five of the eight enzootic strains lacked neuroinvasiveness. Interestingly, highly virulent enzootic strains of WEE virus were isolated from Cx. tarsalis collected in the Sacramento Valley during 1994 and 1995 in the absence of identified human disease. The Fleming strain, the B628(Cl 15) variant, and four enzootic strains from the Sacramento Valley were virulent for baby chickens following subcutaneous inoculation. Thus, inoculation into baby chicks cannot discriminate between WEE viruses that are virulent and avirulent for adult mice.
Ryan Torres - One of the best experts on this subject based on the ideXlab platform.
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Wolbachia in mosquitoes from the Central Valley of California, USA
Parasites & Vectors, 2020Co-Authors: Ryan Torres, Eunis Hernandez, Valeria Flores, Jose Luis Ramirez, Andrea L. JoyceAbstract:Background Wolbachia bacteria are widely distributed throughout terrestrial arthropod species. These bacteria can manipulate reproduction and influence the vector competence of their hosts. Recently, Wolbachia have been integrated into vector control programmes for mosquito management. A number of supergroups and strains exist for Wolbachia , and they have yet to be characterized for many mosquito species. In this study, we examined Wolbachia prevalence and their phylogenetic relationship to other Wolbachia , using mosquitoes collected in Merced County in the Central Valley of California. Methods Adult mosquitoes were collected from 85 sites in Merced County, California in 2017 and 2018. Traditional and quantitative PCR were used to investigate the presence or absence and the density of Wolbachia , using Wolbachia -specific 16S rRNA and Wolbachia- surface protein ( wsp ) genes. The supergroup of Wolbachia was determined, and Multilocus Sequence Typing (MLST) by sequencing five housekeeping genes ( cox A, gat B, fts Z, hcp A and fbp A) was also used to determine Wolbachia supergroup as well as strain. Results Over 7100 mosquitoes of 12 species were collected: Aedes melanimon , Ae . nigromaculis , Ae . vexans , Ae . aegypti , Culex pipiens , Cx . stigmatosoma , Cx . tarsalis , Anopheles franciscanus , An . freeborni , An . punctipennis , Culiseta incidens and Cs . inornata . Eight showed evidence of Wolbachia . To our knowledge, this study is the first to report detection of Wolbachia in five of these species ( Ae . melanimon , Cx . stigmatosoma , Cx . tarsalis , Cs . incidens and Cs . inornata ). Culex pipiens and Cx . stigmatosoma had a high frequency and density of Wolbachia infection, which grouped into supergroup B; Cs . inornata clustered with supergroup A. MLST comparisons identified Cx . pipiens and Cx . stigmatosoma as w Pip strain type 9 supergroup B. Six species had moderate to low (< 14%) frequencies of Wolbachia . Four species were negative, Ae . nigromaculis , An . franciscanus , An . freeborni and Ae . aegypti . Conclusions New records of Wolbachia detection were found in mosquitoes from Merced County, California. Culex stigmatosoma and Cs . inornata were new records for Wolbachia supergroup B and A, respectively. Other species with Wolbachia occurred with low frequency and low density. Detection of Wolbachia in mosquitoes can be used to inform potential vector control applications. Future study of Wolbachia within Cx . stigmatosoma and Cs . inornata in California and through the range of these species could further explore Wolbachia infection in these two species.
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Wolbachia in mosquitoes from the Central Valley of California, USA
Parasites & vectors, 2020Co-Authors: Ryan Torres, Eunis Hernandez, Valeria Flores, Jose Luis Ramirez, Andrea L. JoyceAbstract:Author(s): Torres, Ryan; Hernandez, Eunis; Flores, Valeria; Ramirez, Jose Luis; Joyce, Andrea L | Abstract: BackgroundWolbachia bacteria are widely distributed throughout terrestrial arthropod species. These bacteria can manipulate reproduction and influence the vector competence of their hosts. Recently, Wolbachia have been integrated into vector control programmes for mosquito management. A number of supergroups and strains exist for Wolbachia, and they have yet to be characterized for many mosquito species. In this study, we examined Wolbachia prevalence and their phylogenetic relationship to other Wolbachia, using mosquitoes collected in Merced County in the Central Valley of California.MethodsAdult mosquitoes were collected from 85 sites in Merced County, California in 2017 and 2018. Traditional and quantitative PCR were used to investigate the presence or absence and the density of Wolbachia, using Wolbachia-specific 16S rRNA and Wolbachia-surface protein (wsp) genes. The supergroup of Wolbachia was determined, and Multilocus Sequence Typing (MLST) by sequencing five housekeeping genes (coxA, gatB, ftsZ, hcpA and fbpA) was also used to determine Wolbachia supergroup as well as strain.ResultsOver 7100 mosquitoes of 12 species were collected: Aedes melanimon, Ae. nigromaculis, Ae. vexans, Ae. aegypti, Culex pipiens, Cx. stigmatosoma, Cx. tarsalis, Anopheles franciscanus, An. freeborni, An. punctipennis, Culiseta incidens and Cs. inornata. Eight showed evidence of Wolbachia. To our knowledge, this study is the first to report detection of Wolbachia in five of these species (Ae. melanimon, Cx. stigmatosoma, Cx. tarsalis, Cs. incidens and Cs. inornata). Culex pipiens and Cx. stigmatosoma had a high frequency and density of Wolbachia infection, which grouped into supergroup B; Cs. inornata clustered with supergroup A. MLST comparisons identified Cx. pipiens and Cx. stigmatosoma as wPip strain type 9 supergroup B. Six species had moderate to low (l 14%) frequencies of Wolbachia. Four species were negative, Ae. nigromaculis, An. franciscanus, An. freeborni and Ae. aegypti.ConclusionsNew records of Wolbachia detection were found in mosquitoes from Merced County, California. Culex stigmatosoma and Cs. inornata were new records for Wolbachia supergroup B and A, respectively. Other species with Wolbachia occurred with low frequency and low density. Detection of Wolbachia in mosquitoes can be used to inform potential vector control applications. Future study of Wolbachia within Cx. stigmatosoma and Cs. inornata in California and through the range of these species could further explore Wolbachia infection in these two species.
