Dengue haemoragic fever (DHF) is an infectious disease with high morbidity and mortality rate. The main transmission vector DHF in urban areas is Aedes aegypti. Hanoi is a big city with many favorable factors for Ae. aegypti development, therefore it is at high risk of mosquito-borne diseases. The results of distribution surveys in 2011 in areas at risk of DHF in Hanoi showed that the DI index was 0.15 (0-0.26)
AHI 12.12 (0-19.33)
HI 12.50 (040). B116.13 (5 - 84), BI 20 (in 7 districts). The main sources of Aedes larval were water tanks 500 L (43.62 percent), aquariums (33.47 percent), buckets, barrels, pots or discarded containers, etc. The mosquito indicators when having patients reported were DI 0.1 (0 - 0.25)
AHI8.32 (0-17.50)
HI 13.42 (0 - 30). However, B123.04 (7.5 - 155) did not increase as compared to that in the regular monitoring period.