The relationship between some weather factors and dengue fever in Hanoi in 2009 - 2019

Hanoi is one of the areas where dengue fever (DF) is complicated. To understand the effect of weather factors on DF burden at this local, we explored the relationship between weather components (humidity, rainfall, temperature and sunshine) and the number of dengue cases. Monthly data from 2009 to 2019 were analyzed by time-series regression using negative binomial models with the average over lag periods of 0 – 4 months. The results showed that dengue cases and the temperature had a positive relationship with an increase of 1oC in the number of dengue fever increased by 31.3% (95%CI: 8.9 - 58.1, p < 0.01). The relationship between dengue cases and sunshine hours was inverse, with 1 hour of sunshine increasing the number of dengue fever decreasing -0.9% (95%CI: (-1.4)-(-0.4)), p < 0.01). The relationship between dengue cases and humidity or rainfall was positive. However, there was no statistical significance. This finding confirms that the weather factors influenced the occurrence of DF in Hanoi. Therefore, weather factors need to be considered in controlling DF disease in the context of climate change currently in Vietnam.