Dynamics of flavivirus infection in mosquitoes

Mosquito-borne flaviviruses are emerging as the cause of some of the most serious and widespread arthropod-borne viral diseases in the world. Flavivirus outbreaks are influenced by intrinsic (e.g., viral strain, vector competence, host susceptibility) and extrinsic (e.g., temperature, rainfall, human land use) factors that affect mosquito biology in complex ways. The concept of vectorial capacity organizes and integrates these factors, enabling a clearer understanding of their complex interrelationships, how they affect transmission of vector-borne disease, and how they impact human health. This review focuses on the components of vectorial capacity, providing an update on our current understanding of how selected aspects of mosquito biology, such as longevity, feeding behavior, oviposition habits, and nutrition of adult and immature stages, impact flavivirus transmission cycles and human disease. The influence of extrinsic factors, such as temperature, rainfall, seasonal and multiyear weather patterns, and human behavior that affects mosquito biology, and therefore flavivirus transmission, is explored. Mechanisms of flaviviral perpetuation over adverse seasons and years are addressed. This review also discusses vector competence, recent advances in mosquito genetics, and vector control as they relate to flavivirus transmission and human health. © 2003 Elsevier Inc. All rights reserved.