Dengue vector mosquitoes at a tourist attraction, Ko Samui, in 1995

Usavadee Thavara*
Apiwat Tawatsin*
Prakong Phan-Urai*
Wichai Ngamsak*
Chitti Chansang*
Liu Mingtuan**
Li Zhijun**

Affiliations :
*Division of Medical Entomology, Department of Medical Sciences, Ministry of Public Health
**Guangxi Health and Anti-Epidemic Center, Nanning, Guangxi, People's Republic of China

Source:
Southeast Asian Journal of Tropical Medicine and Public Health 1996; 27(1): 160-163 1996; 27(1): 111-118

Language :
English

Abstract:
      On Ko Samui, Thailand there were two epidemics of dengue hemorrhagic fever (DHF) in 1966 and 1967, followed by endemics up to 1994. Aedes aegypti   and Aedes albopictus   were the vectors. From January to July 1995, 51 cases of DHF were reported, out of these were many foreigners who still suffer from dengue fever and return home with negative impression. We carried out an entomological survey around the island and collected the mosquitos to detect dengue virus by digoxigenin-cDNA probe. The data revealed that Aedes aegypti   and Aedes albopictus   still were abundant and some were infected with dengue virus. Visual larval survey indices (HI, CI and BI) were 90.4, 61.3 and 301.3 respectively. Biting rate (BR) of Aedes mosquitos   was high, the average indoor and outdoor BR were 9.7 and 100.8 mosquitos/man-hour. From 13 pools of mosquitos, 8 strains of dengue virus were detected (61.5%). The results may encourage the local authorities to improve vector surveillance and control before the famous island becomes an unpleasant island.