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Entomologic and virologic investigation of Chikungunya, Singapore.

ABSTRACT: Local transmission of chikungunya, a debilitating mosquito-borne viral disease, was first reported in Singapore in January 2008. After 3 months of absence, locally acquired Chikungunya cases resurfaced in May 2008, causing an outbreak that resulted in a total of 231 cases by September 2008. The circulating viruses were related to East, Central, and South African genotypes that emerged in the Indian Ocean region in 2005. The first local outbreak was due to a wild-type virus (alanine at codon 226 of the envelope 1 gene) and occurred in an area where Aedes aegypti mosquitoes were the primary vector. Strains isolated during subsequent outbreaks showed alanine to valine substitution (A226V) and largely spread in areas predominated by Ae. albopictus mosquitoes. These findings led to a revision of the current vector control strategy in Singapore. This report highlights the use of entomologic and virologic data to assist in the control of chikungunya in disease-endemic areas.

SUBMITTER: Ng LC

PROVIDER: S-EPMC2815960 | biostudies-literature | 2009 Aug

REPOSITORIES: biostudies-literature

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Entomologic and virologic investigation of Chikungunya, Singapore.

Ng Lee-Ching LC Tan Li-Kiang LK Tan Cheong-Huat CH Tan Sharon S Y SS Hapuarachchi Hapuarachchige C HC Pok Kwoon-Yong KY Lai Yee-Ling YL Lam-Phua Sai-Gek SG Bucht Göran G Lin Raymond T P RT Leo Yee-Sin YS Tan Boon-Hian BH Han Hwi-Kwang HK Ooi Peng-Lim S PL James Lyn L Khoo Seow-Poh SP

Emerging infectious diseases 20090801 8

Local transmission of chikungunya, a debilitating mosquito-borne viral disease, was first reported in Singapore in January 2008. After 3 months of absence, locally acquired Chikungunya cases resurfaced in May 2008, causing an outbreak that resulted in a total of 231 cases by September 2008. The circulating viruses were related to East, Central, and South African genotypes that emerged in the Indian Ocean region in 2005. The first local outbreak was due to a wild-type virus (alanine at codon 226 ...[more]

PMID: 19751586

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Entomologic and virologic investigation of Chikungunya, Singapore.

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Entomologic and virologic investigation of Chikungunya, Singapore.

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