Serological investigations of flavivirus prevalence in Khammouane Province, Lao People's Democratic Republic, 2007-2008.

Alexandra Hiscox (1, 2) , Christian H Winter (3) , Phengta Vongphrachanh (3) , Thongchanh Sisouk (3) , Virasack Somoulay (3) , Samlane Phompida (4) , Surinder Kaul (5) , Pany Sananikhom (5) , Thi Yen Nguyen (6) , Richard E Paul (7) , Juliet E Bryant (3, 7) , Paul Brey (1)

1 Institut Pasteur du Laos
2 LSHTM - London School of Hygiene and Tropical Medicine
3 National Center for Laboratory and Epidemiology
4 Center for Malaria, Parasitology, and Entomology
5 Nam Theun 2 Power Company
6 NIHE - Institut National d'Hygiène et d'Épidémiologie de Hanoi
7 IP - Institut Pasteur [Paris]

A large-scale cross-sectional seroprevalence study of dengue (DEN) and Japanese encephalitis (JE) was conducted in Khammouane province, Lao PDR, as part of the initial baseline health impact assessment of the Nam Theun 2 hydroelectric dam construction project. Health surveys were performed between May 2007 and February 2008 with serum samples collected from healthy individuals involved in the resettlement program of 16 villages (total surveyed population 4,369). Hemagglutination inhibition assay using flavivirus antigens (DENV1, DENV3, and JEV) performed on 1,708 plasma specimens revealed 30.4% (519) cross-reactive positives, and 10% (172) and 1.3% (22) positives to JEV or DENV, respectively. Entomological surveys conducted during the rainy season of 2008 indicated the presence of competent flavivirus vectors (Culex vishnui group and Aedes albopictus), although Aedes aegypti was not found. Continued surveillance and investigation is warranted to assess the clinical disease burden of flaviviruses in this area that is undergoing rapid ecological and demographic change.

Domains: Invertebrate Zoology

Alexandra Hiscox, Christian H Winter, Phengta Vongphrachanh, Thongchanh Sisouk, Virasack Somoulay, et al.. Serological investigations of flavivirus prevalence in Khammouane Province, Lao People's Democratic Republic, 2007-2008.. American Journal of Tropical Medicine and Hygiene, 2010, 83 (5), pp.1166-9. ⟨10.4269/ajtmh.2010.09-0480⟩. ⟨pasteur-00830969⟩