Seasonal fluctuation and dengue virus circulation in Southern Vietnam from 2011 to 2020

Abstract

This study aims to describe seasonal fluctuation and dengue virus circulation in Southern Vietnam from 2011 to 2020. This was a retrospective descriptive study which used data from surveillance in 20 provinces or cities in the southern region in the period from 2011 to 2020, focusing on the seasonal
variation of the Aedes population. The results showed that in the last 10 years, the Aedes population tended to increase in the rainy season (from May to November) and decrease in the dry season (from December to April). Breteau Index (BI) maintained above 20 during this period of time. Aedes aegypti vector was dominant over Aedes albopictus with the
record of 100% of the monitoring points. While Aedes albopictus was recorded only in some localities with sporadic density data (DI). This index of Aedes albopictus fluctuated from 0.03 to 0.17 per house. The house index of Aedes albopictus (HI) fluctuated from 3.3% to 13.3%. Circulation of four types of Dengue virus and Zika virus among mosquitoes was reported. Regular surveillance of dengue vectors plays an important role in planning and forecasting related diseases.