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United States Articles found through PubMed 2000-2012

Description

West Nile Virus (WNV) is a mosquito-borne virus that can infect humans. Originally known in East Africa, WNV has now spread throughout the world. The first case of WNV in the western hemisphere was identified in New York in 1999, and within 5 years the disease had spread throughout the United States and into Canada, Latin America, and the Caribbean. While most of WNV infections cause no symptoms, the remaining cases show flu-like symptoms, and can lead to neurological disease or death.

latest article added on November 2013

ArticleFirst AuthorPublished
ASSOCIATIONS BETWEEN TWO MOSQUITO POPULATIONS AND WEST NILE VIRUS IN HARRIS COUNTY, TEXAS, 2003–06 1 DENNETT, JAMES A.2007

ASSOCIATIONS BETWEEN TWO MOSQUITO POPULATIONS AND WEST NILE VIRUS IN HARRIS COUNTY, TEXAS, 2003–06 1

Keywords

West Nile virus, Culex quinquefasciatus, Aedes albopictus, gravid trap, minimum infection rate, Cyanocitta cristata, blue jay, blood meal analysis, WNV

Abstract

Associations between Culex quinquefasciatus, Aedes albopictus and West Nile virus (WNV) activity, temperature, and rainfall in Harris County, Texas 2003–06 are discussed. Human cases were highly correlated to Cx. quinquefasciatus (r = 0.87) and Ae. albopictus (r = 0.78) pools, blue jays (r = 0.83), and Ae. albopictus collected (r = 0.71), but not Cx. quinquefasciatus collected (r = 0.45). Human cases were associated with temperature (r = 0.71), not rainfall (r = 0.29), whereas temperature correlated with Ae. albopictus and Cx. quinquefasciatus collections (r = 0.88 and 0.70, respectively) and Cx. quinquefasciatus pools (r = 0.75), but not Ae. albopictus pools (r = 0.55). Both species (collections and pools) and blue jays were weakly correlated (r ≤ 0.41) with rainfall, but blue jays were better correlated with Cx. quinquefasciatus pools (r = 0.87), compared with Ae. albopictus pools (r = 0.67), Ae. albopictus collections (r = 0.69), and Cx. quinquefasciatus collections (r = 0.46). Peak minimum infection rate for Cx. quinquefasciatus (4.55), and Ae. albopictus (4.41) was in August with highest human cases (17.87), blue jays (55.58), and temperature (29.01°C). Between both species, blood meal analysis indicated 68.18% of Cx. quinquefasciatus mammalian hosts were dog, while 22.72% were human, whereas Ae. albopictus had higher human (44.44%) but fewer dog hosts (22.22%). Ten bird species were identified as hosts for Cx. quinquefasciatus, with northern cardinal and blue jay representing 26.66% and 20.00%, respectively. No bird feeding activity was observed in Ae. albopictus. The earliest and latest human blood meal occurred in May (Ae. albopictus) and November (Cx. quinquefasciatus); 66.66% of human host identifications between both species occurred in October–November, after the seasonal human case peak. Based upon our data, WNV activity in both mosquito species warrants further investigation of their individual roles in WNV ecology within this region.

Authors

Tesh, Robert B., Siirin, Marina, Randle, Yvonne, Guzman, Hilda, Wuithiranyagool, Taweesak, Bueno, Rudy, PARSONS, RAY E., DENNETT, JAMES A., BALA, ADILELKHIDIR, SARGENT, CHRISTOPHER B., HASSAN, HASSAN K., REYNA-NAVA, MARTIN and UNNASCH, THOMAS R.

Year Published

2007

Publication

Journal of the American Mosquito Control Association

Locations
DOI

10.2987/8756-971X(2007)23[264:ABTMPA]2.0.CO;2

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/17939505

A MULTIPLE CAGE–HOLDING, WIND-SENSITIVE VANE DESIGN FOR USE IN GROUND ADULTICIDING EFFICACY TESTING IN HARRIS COUNTY, TEXASVESSEY, NATHAN Y.2007

A MULTIPLE CAGE–HOLDING, WIND-SENSITIVE VANE DESIGN FOR USE IN GROUND ADULTICIDING EFFICACY TESTING IN HARRIS COUNTY, TEXAS

Keywords

Wind-sensitive vane apparatus, treatment cages, ground ultra-low volume testing, WNV

Abstract

A wind-sensitive vane apparatus was designed and implemented specifically to accommodate the attachment of otherwise unidirectional insecticide treatment cages used in ground ultra-low volume mosquito adulticide field tests. This cage support system is useful in keeping the potential West Nile virus and St. Louis encephalitis vector Culex quinquefasciatus caged mosquitoes oriented into the wind during field efficacy tests. Testing capacity for resistance surveillance was tripled during the 2005 season, and more reliable results were achieved as a consequence.

Authors

Bueno, Rudy, VESSEY, NATHAN Y., STARK, PAMELA M. and FLATT, KYLE L.

Year Published

2007

Publication

Journal of the American Mosquito Control Association

Locations
DOI

10.2987/8756-971X(2007)23[237:AMCWVD]2.0.CO;2

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/17847862

Does Feeding on Infected Mosquitoes (Diptera: Culicidae) Enhance the Role of Song Sparrows in the Transmission of Arboviruses in California?Reisen, William K.2007

Does Feeding on Infected Mosquitoes (Diptera: Culicidae) Enhance the Role of Song Sparrows in the Transmission of Arboviruses in California?

Keywords

mosquito, song sparrow, West Nile virus, western equine encephalomyelitis virus, oral infection, WNV

Abstract

Song sparrows, Melopiza melodia, inoculated subcutaneously with either western equine encephalomyelitis virus (family Togaviridae, genus Alphavirus, WEEV) or West Nile virus (family Flaviviridae, genus Flavivirus, WNV) developed elevated viremias, and they were considered to be competent experimental hosts for both viruses. However, birds that ingested from three to 20 mosquitoes containing comparable amounts of either WEEV or WNV failed to become infected, indicating limited oral susceptibility. Comparatively few field-collected birds had antibodies against either WEEV or WNV, indicating that this species was infrequently bitten by infectious mosquitoes in nature and probably was of limited importance in viral amplification.

Authors

Reisen, William K. and Fang, Ying

Year Published

2007

Publication

Journal of Medical Entomology

Locations
DOI

10.1603/0022-2585(2007)44[316:DFOIMD]2.0.CO;2

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/17427703

Behavioral Risks for West Nile Virus Disease, Northern Colorado, 2003Gujral, Indira B.2007

Behavioral Risks for West Nile Virus Disease, Northern Colorado, 2003

Keywords

WNV

Abstract

In 2003, residents in 2 adjacent cities in northern Colorado (Loveland and Fort Collins) had severe outbreaks of human West Nile virus (WNV) disease. Unexpectedly, age-adjusted neuroinvasive disease rates were higher in Loveland (38.6 vs. 15.9 per 100,000), which had a more extensive mosquito control program and fewer mosquitoes. A survey was conducted to assess differences in personal protection and risk practices by each city's residents. During May and June 2004, a random-digit dial telephone survey was conducted among adults to assess personal protection behavioral practices used to prevent WNV infection during the 2003 outbreak. After we adjusted for identified risk factors, Loveland residents were 39% more likely to report seldom or never using N,N-diethyl-m-toluamide (DEET), and ≈30% were more likely to report being outdoors during prime mosquito-biting hours than Fort Collins residents. Personal protective practices may directly influence rates of WNV infection and remain important even when comprehensive community mosquito control measures are implemented.

Authors

Gujral, Indira B., Zielinski-Gutierrez, Emily C., LeBailly, Adrienne and Nasci, Roger

Year Published

2007

Publication

Emerging Infectious Diseases

Locations
DOI

10.3201/eid1303.060941

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/17552095

Crow Deaths Caused by West Nile Virus during WinterDawson, Jennifer R.2007

Crow Deaths Caused by West Nile Virus during Winter

Keywords

WNV

Abstract

In New York, an epizootic of American crow (Corvus brachyrhynchos) deaths from West Nile virus (WNV) infection occurred during winter 2004–2005, a cold season when mosquitoes are not active. Detection of WNV in feces collected at the roost suggests lateral transmission through contact or fecal contamination.

Authors

Eidson, Millicent, Ebel, Gregory D., Kramer, Laura D., Dawson, Jennifer R., Stone, Ward B., Young, David S., Galinski, David S., Pensabene, Jason P. and Franke, Mary A.

Year Published

2007

Publication

Emerging Infectious Diseases

Locations
DOI

10.3201/eid1312.070413

Host-Feeding Patterns of Culex Mosquitoes in Relation to Trap Habitat Patrican, Lisa A.2007

Host-Feeding Patterns of Culex Mosquitoes in Relation to Trap Habitat

Keywords

WNV

Abstract

Mosquito feeding patterns identify vertebrate species potentially involved in the amplification of West Nile virus. In New York, northern cardinals (Cardinalis cardinalis) were the predominant hosts in most habitats. Crow (Corvus sp.) blood meals were most frequently identified from sewage treatment plant and storm water catch basin habitats.

Authors

UNNASCH, THOMAS R., Patrican, Lisa A., Hackett, Laura E., McGowan, Jay W. and Lee, Joon-Hak

Year Published

2007

Publication

Emerging Infectious Diseases

Locations
DOI

10.3201/eid1312.070275

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/18258048

Characterization of a small plaque variant of West Nile virus isolated in New York in 2000Jia, Yongqing2007

Characterization of a small plaque variant of West Nile virus isolated in New York in 2000

Keywords

West Nile virus; Small plaque variant; Wild-type; Temperature sensitivity; Culex pipiens; Vector competence, WNV

Abstract

A small-plaque variant (SP) of West Nile virus (WNV) was isolated in Vero cell culture from kidney tissue of an American crow collected in New York in 2000. The in vitro growth of the SP and parental (WT) strains was characterized in mammalian (Vero), avian (DF-1 and PDE), and mosquito (C6/36) cells. The SP variant replicated less efficiently than did the WT in Vero cells. In avian cells, SP growth was severely restricted at high temperatures, suggesting that the variant is temperature sensitive. In mosquito cells, growth of SP and WT was similar, but in vivo in Culex pipiens (L.) there were substantial differences. Relative to WT, SP exhibited reduced replication following intrathoracic inoculation and lower infection, dissemination, and transmission rates following oral infection. Analysis of the full length sequence of the SP variant identified sequence differences which led to only two amino acid substitutions relative to WT, prM P54S and NS2A V61A.

Authors

Kramer, Laura D., KAUFFMAN, ELIZABETH B., Franke, Mary A., Jia, Yongqing, Moudy, Robin M., Dupuis, Alan P., Ngo, Kiet A., Maffei, Joseph G. and Jerzak, Greta V.S.

Year Published

2007

Publication

Virology

Locations
DOI

10.1016/j.virol.2007.06.008

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/17617432

Environmental and ecological determinants of West Nile virus occurrence in horses in North Dakota, 2002MONGOH, M. NDIVA2007

Environmental and ecological determinants of West Nile virus occurrence in horses in North Dakota, 2002

Keywords

WNV

Abstract

West Nile virus (WNV) outbreak in North Dakota in 2002 included over 569 horse cases, clustered mainly in the eastern and northeastern parts of the state. The pattern of occurrence observed suggested existence of specific environmental and ecological factors that increased the risk for infection and illness in those locations. We developed a predictive model with factors that explained the pattern of WNV occurrence observed. Results indicated that surface elevation, temperature, precipitation, reported WNV-positive birds, reported WNV-positive humans, and reported WNV-positive mosquitoes were important predictors of occurrence in horses. However, case distance from water bodies was not significant in the model. Future predictive models of WNV occurrence in horses should take into account these factors in order to improve accuracy and reliability. Research into other potential determinants such as horse management factors are required to determine more differential risk factors associated with WNV occurrence in horses.

Authors

MONGOH, M. NDIVA, KHAITSA, M. L. and DYER, N. W.

Year Published

2007

Publication

Epidemiology and Infection

Locations
DOI

10.1017/S0950268806006662

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/16753077

Climatic and landscape correlates for potential West Nile virus mosquito vectors in the Seattle regionPecoraro, Heidi L.2007

Climatic and landscape correlates for potential West Nile virus mosquito vectors in the Seattle region

Keywords

WNV

Abstract

Climatic and landscape patterns have been associated with both relative mosquito abundance and transmission of mosquito-borne illnesses in many parts of the world, especially warm and tropical climes. To determine if temperature, precipitation, or degree of urbanization were similarly important in the number of potential mosquito vectors for West Nile virus in the moderately temperate climate of western Washington, mosquitoes were collected using CDC carbon-dioxide/light traps set throughout the Seattle region during the summers of 2003 and 2004. The type and abundance of recovered species were compared to ecological correlates. Temperature and mosquito abundance were positively correlated, while precipitation was not strongly correlated with numbers of mosquitoes. Potential WNV mosquito vectors were most abundant in urban and suburban sites, including sites near communal roosts of American crows (Corvus brachyrhynchos). Exurban sites had the greatest vector species diversity, and Culex pipiens was the most abundant species throughout the region.

Authors

Pecoraro, Heidi L., Day, Heather L., Reineke, Robert, Stevens, Nathan, Withey, John C., Marzluff, John M. and Meschke, J. Scott

Year Published

2007

Publication

Journal of Vector Ecology

Locations
DOI

10.3376/1081-1710(2007)32[22:CALCFP]2.0.CO;2

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/17633422

Land Cover Variation and West Nile Virus Prevalence: Patterns, Processes, and Implications for Disease ControlEzenwa, Vanessa O.2007

Land Cover Variation and West Nile Virus Prevalence: Patterns, Processes, and Implications for Disease Control

Keywords

WNV

Abstract

Identifying links between environmental variables and infectious disease risk is essential to understanding how human-induced environmental changes will effect the dynamics of human and wildlife diseases. Although land cover change has often been tied to spatial variation in disease occurrence, the underlying factors driving the correlations are often unknown, limiting the applicability of these results for disease prevention and control. In this study, we described associations between land cover composition and West Nile virus (WNV) infection prevalence, and investigated three potential processes accounting for observed patterns: (1) variation in vector density; (2) variation in amplification host abundance; and (3) variation in host community composition. Interestingly, we found that WNV infection rates among Culex mosquitoes declined with increasing wetland cover, but wetland area was not significantly associated with either vector density or amplification host abundance. By contrast, wetland area was strongly correlated with host community composition, and model comparisons suggested that this factor accounted, at least partially, for the observed effect of wetland area on WNV infection risk. Our results suggest that preserving large wetland areas, and by extension, intact wetland bird communities, may represent a valuable ecosystem-based approach for controlling WNV outbreaks.

Authors

Godsey, Marvin S., Ezenwa, Vanessa O., Milheim, Lesley E., Coffey, Michelle F., King, Raymond J. and Guptill, Stephen C.

Year Published

2007

Publication

Vector-Borne and Zoonotic Diseases

Locations
DOI

10.1089/vbz.2006.0584

Additional Information:

http://www.ncbi.nlm.nih.gov/pubmed/17627435

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