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Kimberly M. Cheng - One of the best experts on this subject based on the ideXlab platform.
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Exposure of California Quail to Organophosphorus Insecticides in Apple Orchards in the Okanagan Valley, British Columbia
Ecotoxicology, 2001Co-Authors: Laurie Wilson, Pamela A. Martin, John E. Elliott, Pierre Mineau, Kimberly M. ChengAbstract:We studied the exposure and effect of the organophosphate insecticides azinphos-methyl and diazinon on adult California Quail ( Callipepla californica ) in an apple orchard in the Okanagan Valley, British Columbia. Cholinesterase activity was measured in plasma samples ( n =65) collected from 54 individuals either prior to spraying, immediately (
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exposure of California Quail to organophosphorus insecticides in apple orchards in the okanagan valley british columbia
Ecotoxicology, 2001Co-Authors: Laurie K Wilson, Pamela A. Martin, John E. Elliott, Pierre Mineau, Kimberly M. ChengAbstract:We studied the exposure and effect of the organophosphate insecticides azinphos-methyl and diazinon on adult California Quail (Callipepla californica) in an apple orchard in the Okanagan Valley, British Columbia. Cholinesterase activity was measured in plasma samples (n=65) collected from 54 individuals either prior to spraying, immediately (<24 hours) or 10 days after three spray events. Mean plasma cholinesterase levels declined significantly (P<0.05, n=12) to 61% of pre-spray mean activity (controls) immediately following the first spray event, but by ten days had recovered to 86% of mean control activity. Subsequent spray events caused no significant declines in mean plasma cholinesterase activity. Four of the 26 Quail sampled within 24 h of a spray event exhibited plasma-ChE inhibition exceeding 50% inhibition. Radio-tagged Quail (n=25) were monitored throughout the breeding season to determine use of orchards and detect changes in use patterns resulting from the spraying of insecticides. Use of orchards by Quail varied over the summer, with the highest use occurring in May, declining to very low use by July. Quail exhibited a diurnal pattern, roosting in sparsely forested uplands at night, travelling to orchard areas to feed early each morning and returning to roosts at dusk. Orchard use by Quail differed during spray events compared to non-spray times. During the three hour period immediately after spraying (0530–0800), 14–20% of observed Quail were in the orchard, after which use declined to <4%, and returned to 12% by the next day. During non-spray times, 3–13% of radio-tagged the Quail were observed in orchard habitat, with the heaviest use (13%) occurring later in the day (0830–1700 h). Seven radio-tagged Quail were predated during the study period. However, no deaths could be attributed to insecticide poisoning as carcasses were not in suitable condition for testing. It was concluded that adult Quail using orchard habitat early in the summer may be acutely poisoned by anti-cholinesterase insecticides, but the risk of exposure declined over the summer.
William K. Reisen - One of the best experts on this subject based on the ideXlab platform.
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Surveys for Antibodies Against Mosquitoborne Encephalitis Viruses in California Birds, 1996-2013.
Vector-borne and Zoonotic Diseases, 2016Co-Authors: William K. Reisen, Sarah S. WheelerAbstract:Abstract From 1996 through 2013, 54,546 individual birds comprising 152 species and 7 orders were banded, bled, and released at four study areas within California, from which 28,388 additional serum samples were collected at one or more recapture encounters. Of these, 142, 99, and 1929 birds from 41 species were positive for neutralizing antibodies against western equine encephalomyelitis virus (WEEV), St. Louis encephalitis virus (SLEV), or West Nile virus (WNV) at initial capture or recapture, respectively. Overall, 83% of the positive serum samples were collected from five species: House Finch, House Sparrow, Mourning Dove, California Quail, and Western Scrub-Jay. Temporal data supported concurrent arbovirus surveillance and documented the disappearance of birds positive for WEEV in 2008 and SLEV in 2003 and the appearance of birds positive for WNV after its invasion in 2003. Results of these serosurveys agreed well with the host selection patterns of the Culex vectors as described from bloodmeal seque...
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Comparative Thermostability of West Nile, St. Louis Encephalitis, and Western Equine Encephalomyelitis Viruses during Heat Inactivation for Serologic Diagnostics
The American Journal of Tropical Medicine and Hygiene, 2009Co-Authors: Ying Fang, Aaron C. Brault, William K. ReisenAbstract:During the monitoring of arbovirus seroprevalence in wild birds collected in California, we inadvertently made two isolates of western equine encephalomyelitis virus (WEEV) from California Quail sera being tested by plaque reduction neutralization assay for antibodies against St Louis encephalitis (SLEV) and West Nile (WNV) viruses despite heating the sera at 56°C for 30 minutes. These data prompted us to examine the thermostability of these viruses during heat treatment. The flaviviruses, SLEV and WNV, at titers up to 10 6 plaque-forming units (PFU), were readily inactivated by the standard protocol of heating at 56°C for 30 minutes. In contrast, solutions containing 10 5 and 10 6 PFU of WEEV required 2 hours for complete inactivation. Occasional presence of live virus within sera could lead to false negatives using standard plaque reduction neutralization test protocols. The plaque reduction neutralization test (PRNT) is the "gold standard" for serologic diagnostics and relies on anti- bodies within serum samples to specifically neutralize target viruses. However, complement and adventitious viruses within sera can confound PRNTs and lead to false negatives. For this reason, protocols recommend that sera be heated to 56°C for 30 minutes to inactivate complement and remove confound- ing viruses, 1 especially when more than one virus may be cir- culating within the target population. We have been monitoring the prevalence of antibodies against western equine encephalomyelitis virus (WEEV; Togaviridae, Alphavirus ), St. Louis encephalitis virus (SLEV; Flavivi- ridae, Flavivirus ), and West Nile virus (WNV; Flaviviridae , Flavivirus ) in California birds for the past 10 years. In our standard protocol, sera initially are screened against WEEV or flavivirus antigen using an enzyme immunoassay (EIA).
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Repeated West Nile Virus Epidemic Transmission in Kern County, California, 2004–2007
Journal of Medical Entomology, 2009Co-Authors: William K. Reisen, Richard Takahashi, Vincent M Martinez, Brian D. Carroll, Sandra García, Ying Fang, Rob QuiringAbstract:ABSTRACT West Nile virus (WNV) has remained epidemic in Kern County, CA, since its introduction in 2004 through 2007 when the human case annual incidence increased from 6–8 to 17 per 100,000, respectively. The 2007 increase in human infection was associated with contradicting surveillance indicators, including severe drought, warm spring but cool summer temperature anomalies, decreased rural and urban mosquito abundance but increased early season infection in urban Culex quinquefasciatus Say, moderate avian “herd immunity,” and declines in the catch of competent (western scrub-jay and house finch) and noncompetent (California Quail and mourning dove) avian species. The decline in these noncompetent avian hosts may have increased contact with competent avian hosts and perhaps humans. The marked increase in home foreclosures and associated neglected swimming pools increased urban mosquito production sites, most likely contributing to the urban mosquito population and the WNV outbreak within Bakersfield. Coa...
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Role of California (Callipepla californica) and Gambel's (Callipepla gambelii) Quail in the ecology of mosquito-borne encephalitis viruses in California, USA.
Vector-Borne and Zoonotic Diseases, 2006Co-Authors: William K. Reisen, Vincent M Martinez, Sarah S. Wheeler, Sandra García, Ying Fang, Siranoosh Ashtari, Brian D. CarrollAbstract:Gambel's and California Quail were infected repeatedly whenever western equine encephalomyelitis virus (WEEV), St. Louis encephalitis virus (SLEV), and (WNV) West Nile virus were active during summer in California. The timing of virus appearance and Quail infection coincided well with the appearance of chicks in nature, leading us to hypothesize that large coveys containing these non-immune birds could be important in focal virus amplification in rural settings. However, experimental infection studies with chicks, juveniles, and adults of both Quail species using sympatric strains of WEEV, SLEV, and WNV indicated that only immature birds were competent hosts for WEEV, producing viremias sufficiently elevated to efficiently infect Culex tarsalis mosquitoes. Quail were less competent hosts for WNV and were incompetent for SLEV. Large populations of Quail that frequently are infected with SLEV or WNV, but produce low to moderate viremias, may serve as dead end hosts for these viruses. Due to their abundance ...
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avian host and mosquito diptera culicidae vector competence determine the efficiency of west nile and st louis encephalitis virus transmission
Journal of Medical Entomology, 2005Co-Authors: William K. Reisen, Ying Fang, Vincent M MartinezAbstract:Abstract The ability of the invading NY99 strain of West Nile virus (WNV) to elicit an elevated viremia response in California passerine birds was critical for the effective infection of Culex mosquitoes. Of the bird species tested, Western scrub jays, Aphelocoma coerulescens, produced the highest viremia response, followed by house finches, Carpodacus mexicanus, and house sparrows, Passer domesticus. Most likely, few mourning, Zenaidura macroura, or common ground, Columbina passerine, doves and no California Quail, Callipepla californica, or chickens would infect blood-feeding Culex mosquitoes. All Western scrub jays and most house finches succumbed to infection. All avian hosts produced a lower viremia response and survived after infection with an endemic strain of St. Louis encephalitis virus. Culex species varied in their susceptibility to infection with both viruses, with Culex stigmatosoma Dyar generally most susceptible, followed by Culex tarsalis Coquillett, and then Culex p. quinquefasciatus Say....
Vincent M Martinez - One of the best experts on this subject based on the ideXlab platform.
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Repeated West Nile Virus Epidemic Transmission in Kern County, California, 2004–2007
Journal of Medical Entomology, 2009Co-Authors: William K. Reisen, Richard Takahashi, Vincent M Martinez, Brian D. Carroll, Sandra García, Ying Fang, Rob QuiringAbstract:ABSTRACT West Nile virus (WNV) has remained epidemic in Kern County, CA, since its introduction in 2004 through 2007 when the human case annual incidence increased from 6–8 to 17 per 100,000, respectively. The 2007 increase in human infection was associated with contradicting surveillance indicators, including severe drought, warm spring but cool summer temperature anomalies, decreased rural and urban mosquito abundance but increased early season infection in urban Culex quinquefasciatus Say, moderate avian “herd immunity,” and declines in the catch of competent (western scrub-jay and house finch) and noncompetent (California Quail and mourning dove) avian species. The decline in these noncompetent avian hosts may have increased contact with competent avian hosts and perhaps humans. The marked increase in home foreclosures and associated neglected swimming pools increased urban mosquito production sites, most likely contributing to the urban mosquito population and the WNV outbreak within Bakersfield. Coa...
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Role of California (Callipepla californica) and Gambel's (Callipepla gambelii) Quail in the ecology of mosquito-borne encephalitis viruses in California, USA.
Vector-Borne and Zoonotic Diseases, 2006Co-Authors: William K. Reisen, Vincent M Martinez, Sarah S. Wheeler, Sandra García, Ying Fang, Siranoosh Ashtari, Brian D. CarrollAbstract:Gambel's and California Quail were infected repeatedly whenever western equine encephalomyelitis virus (WEEV), St. Louis encephalitis virus (SLEV), and (WNV) West Nile virus were active during summer in California. The timing of virus appearance and Quail infection coincided well with the appearance of chicks in nature, leading us to hypothesize that large coveys containing these non-immune birds could be important in focal virus amplification in rural settings. However, experimental infection studies with chicks, juveniles, and adults of both Quail species using sympatric strains of WEEV, SLEV, and WNV indicated that only immature birds were competent hosts for WEEV, producing viremias sufficiently elevated to efficiently infect Culex tarsalis mosquitoes. Quail were less competent hosts for WNV and were incompetent for SLEV. Large populations of Quail that frequently are infected with SLEV or WNV, but produce low to moderate viremias, may serve as dead end hosts for these viruses. Due to their abundance ...
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avian host and mosquito diptera culicidae vector competence determine the efficiency of west nile and st louis encephalitis virus transmission
Journal of Medical Entomology, 2005Co-Authors: William K. Reisen, Ying Fang, Vincent M MartinezAbstract:Abstract The ability of the invading NY99 strain of West Nile virus (WNV) to elicit an elevated viremia response in California passerine birds was critical for the effective infection of Culex mosquitoes. Of the bird species tested, Western scrub jays, Aphelocoma coerulescens, produced the highest viremia response, followed by house finches, Carpodacus mexicanus, and house sparrows, Passer domesticus. Most likely, few mourning, Zenaidura macroura, or common ground, Columbina passerine, doves and no California Quail, Callipepla californica, or chickens would infect blood-feeding Culex mosquitoes. All Western scrub jays and most house finches succumbed to infection. All avian hosts produced a lower viremia response and survived after infection with an endemic strain of St. Louis encephalitis virus. Culex species varied in their susceptibility to infection with both viruses, with Culex stigmatosoma Dyar generally most susceptible, followed by Culex tarsalis Coquillett, and then Culex p. quinquefasciatus Say....
Ying Fang - One of the best experts on this subject based on the ideXlab platform.
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Comparative Thermostability of West Nile, St. Louis Encephalitis, and Western Equine Encephalomyelitis Viruses during Heat Inactivation for Serologic Diagnostics
The American Journal of Tropical Medicine and Hygiene, 2009Co-Authors: Ying Fang, Aaron C. Brault, William K. ReisenAbstract:During the monitoring of arbovirus seroprevalence in wild birds collected in California, we inadvertently made two isolates of western equine encephalomyelitis virus (WEEV) from California Quail sera being tested by plaque reduction neutralization assay for antibodies against St Louis encephalitis (SLEV) and West Nile (WNV) viruses despite heating the sera at 56°C for 30 minutes. These data prompted us to examine the thermostability of these viruses during heat treatment. The flaviviruses, SLEV and WNV, at titers up to 10 6 plaque-forming units (PFU), were readily inactivated by the standard protocol of heating at 56°C for 30 minutes. In contrast, solutions containing 10 5 and 10 6 PFU of WEEV required 2 hours for complete inactivation. Occasional presence of live virus within sera could lead to false negatives using standard plaque reduction neutralization test protocols. The plaque reduction neutralization test (PRNT) is the "gold standard" for serologic diagnostics and relies on anti- bodies within serum samples to specifically neutralize target viruses. However, complement and adventitious viruses within sera can confound PRNTs and lead to false negatives. For this reason, protocols recommend that sera be heated to 56°C for 30 minutes to inactivate complement and remove confound- ing viruses, 1 especially when more than one virus may be cir- culating within the target population. We have been monitoring the prevalence of antibodies against western equine encephalomyelitis virus (WEEV; Togaviridae, Alphavirus ), St. Louis encephalitis virus (SLEV; Flavivi- ridae, Flavivirus ), and West Nile virus (WNV; Flaviviridae , Flavivirus ) in California birds for the past 10 years. In our standard protocol, sera initially are screened against WEEV or flavivirus antigen using an enzyme immunoassay (EIA).
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Repeated West Nile Virus Epidemic Transmission in Kern County, California, 2004–2007
Journal of Medical Entomology, 2009Co-Authors: William K. Reisen, Richard Takahashi, Vincent M Martinez, Brian D. Carroll, Sandra García, Ying Fang, Rob QuiringAbstract:ABSTRACT West Nile virus (WNV) has remained epidemic in Kern County, CA, since its introduction in 2004 through 2007 when the human case annual incidence increased from 6–8 to 17 per 100,000, respectively. The 2007 increase in human infection was associated with contradicting surveillance indicators, including severe drought, warm spring but cool summer temperature anomalies, decreased rural and urban mosquito abundance but increased early season infection in urban Culex quinquefasciatus Say, moderate avian “herd immunity,” and declines in the catch of competent (western scrub-jay and house finch) and noncompetent (California Quail and mourning dove) avian species. The decline in these noncompetent avian hosts may have increased contact with competent avian hosts and perhaps humans. The marked increase in home foreclosures and associated neglected swimming pools increased urban mosquito production sites, most likely contributing to the urban mosquito population and the WNV outbreak within Bakersfield. Coa...
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Role of California (Callipepla californica) and Gambel's (Callipepla gambelii) Quail in the ecology of mosquito-borne encephalitis viruses in California, USA.
Vector-Borne and Zoonotic Diseases, 2006Co-Authors: William K. Reisen, Vincent M Martinez, Sarah S. Wheeler, Sandra García, Ying Fang, Siranoosh Ashtari, Brian D. CarrollAbstract:Gambel's and California Quail were infected repeatedly whenever western equine encephalomyelitis virus (WEEV), St. Louis encephalitis virus (SLEV), and (WNV) West Nile virus were active during summer in California. The timing of virus appearance and Quail infection coincided well with the appearance of chicks in nature, leading us to hypothesize that large coveys containing these non-immune birds could be important in focal virus amplification in rural settings. However, experimental infection studies with chicks, juveniles, and adults of both Quail species using sympatric strains of WEEV, SLEV, and WNV indicated that only immature birds were competent hosts for WEEV, producing viremias sufficiently elevated to efficiently infect Culex tarsalis mosquitoes. Quail were less competent hosts for WNV and were incompetent for SLEV. Large populations of Quail that frequently are infected with SLEV or WNV, but produce low to moderate viremias, may serve as dead end hosts for these viruses. Due to their abundance ...
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avian host and mosquito diptera culicidae vector competence determine the efficiency of west nile and st louis encephalitis virus transmission
Journal of Medical Entomology, 2005Co-Authors: William K. Reisen, Ying Fang, Vincent M MartinezAbstract:Abstract The ability of the invading NY99 strain of West Nile virus (WNV) to elicit an elevated viremia response in California passerine birds was critical for the effective infection of Culex mosquitoes. Of the bird species tested, Western scrub jays, Aphelocoma coerulescens, produced the highest viremia response, followed by house finches, Carpodacus mexicanus, and house sparrows, Passer domesticus. Most likely, few mourning, Zenaidura macroura, or common ground, Columbina passerine, doves and no California Quail, Callipepla californica, or chickens would infect blood-feeding Culex mosquitoes. All Western scrub jays and most house finches succumbed to infection. All avian hosts produced a lower viremia response and survived after infection with an endemic strain of St. Louis encephalitis virus. Culex species varied in their susceptibility to infection with both viruses, with Culex stigmatosoma Dyar generally most susceptible, followed by Culex tarsalis Coquillett, and then Culex p. quinquefasciatus Say....
John E. Elliott - One of the best experts on this subject based on the ideXlab platform.
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Exposure of California Quail to Organophosphorus Insecticides in Apple Orchards in the Okanagan Valley, British Columbia
Ecotoxicology, 2001Co-Authors: Laurie Wilson, Pamela A. Martin, John E. Elliott, Pierre Mineau, Kimberly M. ChengAbstract:We studied the exposure and effect of the organophosphate insecticides azinphos-methyl and diazinon on adult California Quail ( Callipepla californica ) in an apple orchard in the Okanagan Valley, British Columbia. Cholinesterase activity was measured in plasma samples ( n =65) collected from 54 individuals either prior to spraying, immediately (
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exposure of California Quail to organophosphorus insecticides in apple orchards in the okanagan valley british columbia
Ecotoxicology, 2001Co-Authors: Laurie K Wilson, Pamela A. Martin, John E. Elliott, Pierre Mineau, Kimberly M. ChengAbstract:We studied the exposure and effect of the organophosphate insecticides azinphos-methyl and diazinon on adult California Quail (Callipepla californica) in an apple orchard in the Okanagan Valley, British Columbia. Cholinesterase activity was measured in plasma samples (n=65) collected from 54 individuals either prior to spraying, immediately (<24 hours) or 10 days after three spray events. Mean plasma cholinesterase levels declined significantly (P<0.05, n=12) to 61% of pre-spray mean activity (controls) immediately following the first spray event, but by ten days had recovered to 86% of mean control activity. Subsequent spray events caused no significant declines in mean plasma cholinesterase activity. Four of the 26 Quail sampled within 24 h of a spray event exhibited plasma-ChE inhibition exceeding 50% inhibition. Radio-tagged Quail (n=25) were monitored throughout the breeding season to determine use of orchards and detect changes in use patterns resulting from the spraying of insecticides. Use of orchards by Quail varied over the summer, with the highest use occurring in May, declining to very low use by July. Quail exhibited a diurnal pattern, roosting in sparsely forested uplands at night, travelling to orchard areas to feed early each morning and returning to roosts at dusk. Orchard use by Quail differed during spray events compared to non-spray times. During the three hour period immediately after spraying (0530–0800), 14–20% of observed Quail were in the orchard, after which use declined to <4%, and returned to 12% by the next day. During non-spray times, 3–13% of radio-tagged the Quail were observed in orchard habitat, with the heaviest use (13%) occurring later in the day (0830–1700 h). Seven radio-tagged Quail were predated during the study period. However, no deaths could be attributed to insecticide poisoning as carcasses were not in suitable condition for testing. It was concluded that adult Quail using orchard habitat early in the summer may be acutely poisoned by anti-cholinesterase insecticides, but the risk of exposure declined over the summer.
