Mobility and non-household environments: Understanding dengue transmission patterns in urban contexts

Area of Science:

• Epidemiology
• Urban Planning
• Vector-borne Diseases

Background:

• Households (HH) are traditionally considered primary sites for dengue and arbovirus transmission.
• Emerging evidence indicates significant roles for non-household (NH) environments like workplaces and markets.
• Agent-based models suggest over half of arbovirus infections originate in NH settings.

Purpose of the Study:

• To investigate how urban spatial configurations of NH sites influence dengue transmission.
• To assess the impact of human and vector mobility between HH and NH environments.
• To understand the relationship between spatial distribution of NH sites and infection dynamics.

Main Methods:

• Expansion of an agent-based model (ABM) calibrated with field data from Kenya.
• Simulation of human and vector movement under varying spatial configurations of NH buildings (scattered, centered, clustered).
• Assessment of travel patterns, including the number of people moving and distances traveled between HH and NH.

Main Results:

• The volume of human movement between HH and NH environments was the most significant factor increasing dengue case numbers.
• Scattered configurations of NH sites resulted in higher case numbers compared to centered or clustered arrangements.
• Travel distance from HH to NH had minimal impact on overall dengue burden but affected infection clustering.

Conclusions:

• Non-household environments are critical hubs for arbovirus transmission, facilitating spread between HH and NH settings.
• Human mobility patterns are a primary driver of dengue dynamics in urban areas.
• Urban planning and understanding human movement are essential for effective dengue control strategies.