Autor(es): LaBeaud A Desiree, Banda Tamara, Brichard Julie, Muchiri Eric M, Mungai Peter L, Mutuku Francis M, Borland Erin, Gildengorin Ginny, Pfeil Sarah, Teng Crystal Y, Long Kristin, Heise Mark, Powers Ann M, Kitron Uriel, King Charles H

Resumo: Chikungunya virus (CHIKV) - o'nyong nyong virus (ONNV) are mosquito-borne alphaviruses endemic in East Africa that cause acute febrile illness - arthritis. The objectives of this study were to measure the seroprevalence of CHIKV - ONNV in coastal Kenya - link it to demographics - other risk factors. Demographic - exposure questionnaires were administered to 1,848 participants recruited from two village clusters (Milalani-Nganja - Vuga) in 2009. Sera were tested for alphavirus exposure using st-ardized CHIKV IgG ELISA protocols - confirmed with plaque reduction neutralization tests (PRNT). Logistic regression models were used to determine the variables associated with seropositivity. Weighted K test for global clustering of houses with alphavirus positive participants was performed for distance ranges of 50-1,000 meters, - G* statistic - kernel density mapping were used to identify locations of higher seroprevalence. 486 (26%) participants were seropositive by IgG ELISA. Of 443 PRNT confirmed positives, 25 samples (6%) were CHIKV+, 250 samples (56%) were ONNV+, - 168 samples (38%) had high titers for both. Age was significantly associated with seropositivity (OR 1.01 per year, 95% C.I. 1.00-1.01); however, younger adults were more likely to be seropositive than older adults. Males were less likely to be seropositive (p<0.05; OR 0.79, 95% C.I. 0.64-0.97). Adults who owned a bicycle (p<0.05; OR 1.37, 95% C.I. 1.00-1.85) or motor vehicle (p<0.05; OR 4.64, 95% C.I. 1.19-18.05) were more likely to be seropositive. Spatial analysis demonstrated hotspots of transmission within each village - clustering among local households in Milalani-Nganja, peaking at the 200-500m range. Alphavirus exposure, particularly ONNV exposure, is common in coastal Kenya with ongoing interepidemic transmission of both ONNV - CHIKV. Women - adults were more likely to be seropositive. Household location may be a defining factor for the ecology of alphaviral transmission in this region.

Imprenta: PLoS Neglected Tropical Diseases, v. 9, n. 2, p. e0003436, 2015

Identificador do objeto digital: 10.1371/journal.pntd.0003436

Descritores: Chikungunya virus - Pathogenesis ; Chikungunya virus - Serology ; Chikungunya virus - Viral infections ; Chikungunya virus - Serology ; Chikungunya Virus - Virus ; Chikungunya virus - Transmission ; Chikungunya virus - Chikungunya fever ; Chikungunya virus - Epidemiology ; Chikungunya virus - Immunology ; Chikungunya virus - Public health

Data de publicação: 2015