Open AccessProspective field study of transovarial dengue‐virus transmission by two different forms of Aedes aegypti in an urban area of Bangkok, Thailand
Author(s) -
Thongrungkiat Supatra,
Maneekan Pannamas,
Wasinpiyamongkol Ladawan,
Prummongkol Samrerng
Publication year - 2011
Publication title -
journal of vector ecology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.688
H-Index - 51
eISSN - 1948-7134
pISSN - 1081-1710
DOI - 10.1111/j.1948-7134.2011.00151.x
Subject(s) - dengue fever , aedes aegypti , biology , transovarial transmission , dengue virus , virology , veterinary medicine , transmission (telecommunications) , serotype , virus , aedes , aedes albopictus , larva , ecology , medicine , electrical engineering , engineering
A prospective field study was conducted to determine transovarial dengue‐virus transmission in two forms of Aedes aegypti mosquitoes in an urban district of Bangkok, Thailand. Immature Aedes mosquitoes were collected monthly for one year and reared continuously until adulthood in the laboratory. Mosquitoes assayed for dengue virus were processed in pools and their dengue virus infection status was determined by one‐step RT‐PCR and nested‐PCR methods. Of a total 15,457 newly emerged adult Ae. aegypti , 98.2% were dark and 1.8% of the pale form. The results showed that the minimum infection rate (MIR) by transovarial transmission (TOT) of dengue virus during the one‐year study ranged between 0 to 24.4/1,000 mosquitoes. Dengue virus TOT increased gradually during the hot summer months, reaching a peak in April‐June, while dengue cases peaked in September, a rainy month near the end of the rainy season. Therefore, mosquito infections due to TOT were prevalent four months before a high incidence of human infections. TOT dengue virus infections occurred in both forms of Ae. aegypti . All four dengue serotypes were detected, with DEN‐4 predominant, followed by DEN‐3, DEN‐1, and DEN‐2, respectively.