Weather patterns help predict dengue fever outbreaks

High temperatures, humidity and low wind speed are associated with high occurrence of dengue fever according to a study published in the open access journal BMC Public Health.

Dengue fever is a viral disease transmitted by mosquitoes in tropical and subtropical regions of the world. It is one of the most significant insect-borne diseases found in humans, with 2.5 billion people living in high-risk areas globally. In recent years, the number of cases occurring has increased dramatically.

Being able to predict the trend of dengue fever facilitates early public heath responses to minimize morbidity and mortality, according to the report Oct. 26 in ScienceDaily.

A research team led by Qiyong Liu of the State Key Laboratory for Infectious Disease Prevention and Control, and China CDC, and Linwei Tian of the Stanley Ho Centre for Emerging Infectious Diseases, School of Public Health and Primary Care, Chinese University of Hong Kong, correlated weather conditions, including minimum and maximum temperature, wind velocity, humidity and rainfall with the number of cases of dengue fever in the city of Guangzhou, capital city of Guangdong province, China, from 2001 until 2006.

The authors suggest that the effects of humidity and temperature are likely to be related to mosquito survival; low humidity and cooler temperatures decrease mosquito survival. Wind speed affects mosquito flying, so high wind velocities lead to lower density of mosquitoes.

But the authors point out "the transmission of dengue fever is more complex, and is influenced by community intervention measures, human behavioral influences on mosquito population and human-mosquito interaction," and conclude, "future studies require studying mosquito populations."