Temperature affects viral kinetics and vectorial capacity of

Area of Science:

• Medical Entomology
• Viral Pathogenesis
• Climate Change Impact

Background:

• Rising global temperatures and extreme weather facilitate the spread of vector-borne diseases.
• Aedes aegypti mosquitoes transmit arboviruses like dengue and Mayaro, posing significant public health risks, particularly in low-income regions.
• The increasing co-circulation and co-infection of these viruses highlight the need to understand vector contributions.

Approach:

• Investigated single and co-infections of Mayaro virus and dengue virus in Aedes aegypti mosquitoes and cell lines.
• Assessed vector competence, infection, dissemination, and transmission at moderate (27°C) and hot (32°C) temperatures.
• Quantified viral interactions and temperature effects on mosquito mortality and viral kinetics.

Key Points:

• Temperature significantly impacts both dengue and Mayaro virus infections, with synergistic effects observed during co-infection.
• Dengue virus exhibited faster replication and higher titers in co-infected mosquitoes across temperatures.
• Higher temperatures exacerbated mosquito mortality and enhanced vector competence and capacity for both viruses, particularly at earlier time points post-infection.

Conclusions:

• Contrasting viral kinetics suggest differing thermal optima, with alphaviruses (Mayaro) potentially favoring cooler temperatures and flaviviruses (dengue) thriving in warmer conditions.
• Co-infection dynamics are temperature-dependent, influencing viral spread and mosquito survival.
• Further research is crucial to elucidate the complex interplay of co-infection and variable temperature regimes on vector-borne disease transmission.