Climate change and Aedes albopictus risks in China: current impact and future projection

Area of Science:

• Environmental Science
• Epidemiology
• Climate Science

Background:

• General Circulation Models (GCMs) are typically used to predict future dengue risk based on climate change, but their validation and uncertainty assessment are challenging.
• Observed climate changes may diverge significantly from GCM predictions, necessitating alternative approaches for risk assessment.

Purpose of the Study:

• To utilize observed climate trends for predicting the future distribution of Aedes albopictus (the primary vector for dengue) in China.
• To assess the impact of observed climate changes on dengue risk and the associated at-risk population.

Main Methods:

• Collected Aedes albopictus surveillance data and observed climate records from 80 meteorological stations (1970-2021).
• Analyzed climate trends and predicted future climate for 2050 and 2080.
• Developed a classification tree model to predict Aedes albopictus distribution based on climatic variables and projected future distributions.

Main Results:

• Winter-early spring temperatures and summer precipitation were key predictors of Aedes albopictus prevalence.
• Observed temperature increases in China from 1970-2021 were substantial, particularly in February-April.
• Projected future dengue risk areas in 2050 and 2080 are expected to cover nearly all of China, expanding the risk period and increasing the at-risk population to 1.2 billion.

Conclusions:

• Observed climate change in China may exceed GCM predictions.
• Continued climate trends are likely to lead to a significant expansion of dengue risk across China, affecting a larger population.