The Experts below are selected from a list of 360 Experts worldwide ranked by ideXlab platform
Chantal B F Vogels - One of the best experts on this subject based on the ideXlab platform.
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effect of Overwintering on survival and vector competence of the west nile virus vector culex pipiens
Parasites & Vectors, 2019Co-Authors: Constantianus J M Koenraadt, Tim W R Mohlmann, Niels O Verhulst, Jeroen Spitzen, Chantal B F VogelsAbstract:West Nile virus (WNV) is a mosquito-borne virus that is mainly transmitted among birds by Culex pipiens mosquitoes. The species Cx. pipiens consists of two biotypes named pipiens and molestus, which together can form hybrids. One of the major distinctions between the biotypes is their Overwintering behaviour. Adults of biotype pipiens diapause during winter, whereas biotype molestus remains actively blood-feeding. Diapausing may affect survival and vector competence of biotype pipiens. The aims of this study were therefore to identify the biotype composition of diapausing Cx. pipiens mosquitoes, to quantify survival throughout the autumn and winter months, and to determine effects of Overwintering on vector competence of emerging Cx. pipiens mosquitoes for WNV. Diapausing mosquitoes were collected at two typical Overwintering locations in the Netherlands. A selection of Cx. pipiens mosquitoes was identified to biotype using real-time PCR. Survival of diapausing Cx. pipiens mosquitoes during autumn and winter was monitored by placing cages with either field-collected or laboratory-reared females in houses and sheds. Vector competence of field-collected (diapausing) and laboratory-reared (non-diapausing) Cx. pipiens mosquitoes was determined to gain insight in the effect of Overwintering on WNV transmission. The majority (92%) of diapausing Cx. pipiens females were identified as biotype pipiens. More than 70% of diapausing Cx. pipiens mosquitoes was able to survive for more than four months in sheds, whereas diapausing in houses resulted in 100% mortality in that same period. In contrast, non-diapausing Cx. pipiens biotype pipiens mosquitoes reared in the laboratory died within a week in both houses and sheds. Vector competence of Cx. pipiens mosquitoes that had diapaused during the autumn and winter months was comparable to non-diapausing laboratory-reared mosquitoes. This study confirms that the majority of Cx. pipiens mosquitoes in their typical Overwintering site belongs to the pipiens biotype. It shows that more than two-third of diapausing Cx. pipiens mosquitoes is able to survive winter under sheltered winter conditions. Finally, vector competence for WNV of mosquitoes that emerge from Overwintering sites is not affected by their relatively old age.
Robert S Lanciotti - One of the best experts on this subject based on the ideXlab platform.
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west nile virus in Overwintering culex mosquitoes new york city 2000
Emerging Infectious Diseases, 2001Co-Authors: Roger S Nasci, Harry M Savage, Dennis J White, James R Miller, Bruce C Cropp, Marvin S Godsey, Amy J Kerst, Paul Bennett, Kristy L Gottfried, Robert S LanciottiAbstract:After the 1999 West Nile (WN) encephalitis outbreak in New York, 2,300 Overwintering adult mosquitoes were tested for WN virus by cell culture and reverse transcriptase-polymerase chain reaction. WN viral RNA and live virus were found in pools of Culex mosquitoes. Persistence in Overwintering Cx. pipiens may be important in the maintenance of WN virus in the northeastern United States.
Roger S Nasci - One of the best experts on this subject based on the ideXlab platform.
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west nile virus in Overwintering culex mosquitoes new york city 2000
Emerging Infectious Diseases, 2001Co-Authors: Roger S Nasci, Harry M Savage, Dennis J White, James R Miller, Bruce C Cropp, Marvin S Godsey, Amy J Kerst, Paul Bennett, Kristy L Gottfried, Robert S LanciottiAbstract:After the 1999 West Nile (WN) encephalitis outbreak in New York, 2,300 Overwintering adult mosquitoes were tested for WN virus by cell culture and reverse transcriptase-polymerase chain reaction. WN viral RNA and live virus were found in pools of Culex mosquitoes. Persistence in Overwintering Cx. pipiens may be important in the maintenance of WN virus in the northeastern United States.
Richard A. Bowen - One of the best experts on this subject based on the ideXlab platform.
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persistent west nile virus infection in the house sparrow passer domesticus
Archives of Virology, 2009Co-Authors: Nicole M Nemeth, Ginger Young, Christina Ndaluka, Helle Bielefeldtohmann, Nicholas Komar, Richard A. BowenAbstract:Long-term persistence of West Nile virus (WNV) infection within vertebrate reservoir hosts is a potential mechanism for Overwintering of this (and other) arbovirus(es) at temperate latitudes. The house sparrow (Passer domesticus), an established amplifying host for WNV and other arboviruses, was used as a model to confirm chronicity of WNV infection in passerine birds and to evaluate the feasibility of two Overwintering mechanisms: blood-borne infection of arthropod vectors (recrudescence) and oral infection of vertebrate reservoir hosts (ingestion of infected tissues through predation). WNV-inoculated sparrows were monitored for persistent infection for up to 2 years. Infectious virus persisted in tissues through 43 days, but not in sera beyond 6 days. Viral RNA persisted in tissues through 65 days. Chronicity of WNV infection in some tissues, but not blood, supports the predation mechanism of WNV Overwintering, but not recrudescence. RNA persistence impacts interpretation and etiologic determination of avian mortality.
K F A Walters - One of the best experts on this subject based on the ideXlab platform.
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low temperature mortality and Overwintering of the western flower thrips frankliniella occidentalis thysanoptera thripidae
Bulletin of Entomological Research, 1997Co-Authors: J R Mcdonald, J S Bale, K F A WaltersAbstract:AbstractThe UK glasshouses in which the western flower Frankliniella thrips occidentalis(Pergande) is prevalent offer protection from adverse winter conditions. As such,F. occidentalis may not have been exposed to selection for cold tolerance that wouldallow successful Overwintering in the field. In this study, the cold tolerance of larvaland adult F. occidentalis has been assessed in the laboratory. Both age groups showpre-freeze mortality in chronic and acute cold exposures though adults are morecold hardy. Larvae and adults are both able to increase their cold tolerance inresponse to a combination of lower temperatures and decreased photoperiod. Fieldexperimentation confirmed tha F.t occidentalis is unlikely to survive for the durationof a harsh UK winter, but a level of cold tolerance that would be adequate forsurvival in mild winters or for short exposures at sub-zero temperatures wasobserved.IntroductionThe western flower thrip Frankliniellas occidentalis (Per-gande) (Thysanoptera wa: Thripidae firss t recorde i)n dBritain in 1986 and sinc hase becom a pese ot majof reconomic importanc ien glasshouses acros ths e UK, causingsignificant damag teo its man y host plant bsy feeding andoviposition, as wel al s bein ag vecto for planr t viruses.Control of F. occidentalis is difficult becaus of widespreae dresistance to major classe of insecticids e (Rob et al.,b 1987;Macdonald, 1993a,b).The global spread of F. occidentalis has been facilitate bdyinternational trad ien planting materia anl d the availabilityof glasshouses that provide suitabl fo popure condition- slation developmen and obviatt the e nee d to tolerat theeexternal environment prevalen in thte area of introduction.Because of this, F. occidentalis may not have been subjectedto selectio fon r th abilite tyo tolerate unfavourable fieldconditions suc ahs thos e encountered during temperatewinters.Frankliniella occidentalis has a typical thrips life cycle withan egg (produce d either sexuall or parthenogenetically) y ,two active larval instars, two relatively passive, non-feeding•Author fo correspondencer .stages (propup ana d pupa) and adult. Adults appea tor bethe dominant Overwintering form, thoug ihs difficult there yin identifyin thg e immatur e stage osf thrips that have beencollected from overwinterin tgo assemblage th speciee s slevel (Chamber s Chamberli etn al., 1992 Ch; oet al., 1995) I.n the USA, F. occidentalis is able to overwinteroutdoors in Texas (Chamber & Sitess, 1989), Georgia,California (Chamberli et al., 1992)n , North Carolin (Choaet al., 1995 an) d even as far north as Pennsylvania (Fellandet al., 1993 b)y exploiting protected microclimate osn eitherplants, in soil or under leaf litter and debris. However, winterconditions in Southern Ontario (Canada and Denmar) k aretoo severe for successful Overwintering by field collecte anddlaboratory cultures of F. occidentalis (Broadbent & Hunt, 1991;Br^>dsgaard, 1993) I.t is possible that the failure to establishpermanent field population at higsh latitude iss becaus e ofinadequate cold tolerance th mildee, wherear wintes rcondition s encountere at lowed latitude allow establish-ment of F. occidentalis year-round (Br^dsgaard, 1993).If establishmen otf a permanent field populatio in the nUK is prevented by winter conditions, occidentalis F. wil bl emaintained through winter primaril in glasshousesy . In thiscase, in winte anr d spring, management strategie can be sdirected specifically against glasshouse ac coloniet as s thatpopulation reservoirs, obviatin the neegd to consider field
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the ecology of insect Overwintering
1993Co-Authors: Simon R Leather, K F A Walters, J S BaleAbstract:Foreword 1. Introduction 2. The Overwintering locale - suitability and selection 3. The stimuli controlling diapause and Overwintering 4. Insect cold-hardiness 5. Costs and benefits of Overwintering 6. Prediction and control Bibliography Index.
