Globe-Trotting Aedes aegypti and Aedes albopictus: Risk Factors for Arbovirus Pandemics

Abstract

Introduction: Two species of Aedes (Ae.) mosquitoes (Ae. aegypti and Ae. albopictus) are primary vectors for emerging arboviruses that are a significant threat to public health and economic burden worldwide. Distribution of these vectors and the associated arboviruses, such as dengue virus, chikungunya virus, yellow fever virus, and Zika virus, was for a long time restricted by geographical, ecological, and biological factors. Presently, arbovirus emergence and dispersion are more rapid and geographically widespread, largely due to expansion of the range for these two mosquitoes that have exploited the global transportation network, land perturbation, and failure to contain the mosquito population coupled with enhanced vector competence. Ae. aegypti and Ae. albopictus may also sustain transmission between humans without having to depend on their natural reservoir forest cycles due to arthropod adaptation to urbanization. Currently, there is no single strategy that is adequate to control these vectors, especially when managing arbovirus outbreaks. Objective: This review aimed at presenting the characteristics and abilities of Ae. aegypti and Ae. albopictus, which can drive a global public health risk, and suggests strategies for prevention and control. Methods: This review presents the geographic range, reproduction and ecology, vector competence, genetic evolution, and biological and chemical control of these two mosquito species and how they have changed and developed over time combined with factors that may drive pandemics and mitigation measures. Conclusion: We suggest that more efforts should be geared toward the development of a concerted multidisciplinary approach.

Keywords: arboviruses; mosquitoes; pandemic risk; vector control.

FIG. 1.

Global distribution of Ae. aegypti using climatic and surveillance data collected up to 2015. Color images are available online.

FIG. 2.

Global distribution of Ae. albopictus using climatic and surveillance data collected up to 2015. Color images are available online.

FIG. 3.

Ae. aegypti (left) and Ae. albopictus (right) adult mosquitoes. Morphologically, both are dark in color with white strips on their backs and legs. However, Ae. albopictus is smaller, with a single, longitudinal, silvery dorsal stripe, while Ae. aegypti has a silvery, lyre-shaped dorsal pattern on its scutum (photo, Anders Lindström).

FIG. 4.

A schematic outline of tasks and individual components to be considered for risk analysis and risk mitigation.

FIG. 5.

Insights for tackling epidemics. The information in the rectangular boxes indicates how different components involved in tackling arboviruses epidemics linked to Ae. aegypti and Ae. albopictus relate with each other for better preparedness and strength to fight epidemics. The plus sign designates joint efforts, whereas the arrows indicate the key activities that will help to link research outputs to early warning and response capacity outcomes and disease control.