Speaker：Daihai Zhou (The Hong Kong Polytechnic University)

Time：2025-11-14 10:00

Location：Conference Room C610 at Administration Building at Haiyun Campus

Abstract:

The global resurgence of chikungunya virus in 2025, with outbreaks reported in the Indian Ocean, Africa, and the Americas, has raised new public health concern. Brazil remains one of the most heavily affected countries, with more than 180,000 reported cases. This study investigates the epidemic dynamics of CHIKV in comparison with dengue virus (DENV), focusing on Brazil from 2017 to 2025. Using national surveillance data, we analyze spatiotemporal heterogeneity, demographic distributions, and infection attack rates for both arboviruses. We find that chikungunya exhibits greater regional heterogeneity and lower temporal synchrony than dengue, likely due to differences in basic reproduction number (R0) and population immunity. Age-specific case burdens are highest among working-age adults, while infants and the elderly experience greater severity. To reconstruct long-term epidemic trajectories at the regional level, we develop a modified SEIR5S compartmental model.