Arboviruses and lemurs in Madagascar: a preliminary note

Area of Science:

• Veterinary epidemiology
• Arbovirology
• Primate immunology

Background:

• Arboviruses pose a significant public health threat globally.
• Understanding wildlife reservoirs is crucial for predicting and preventing zoonotic spillover events.
• Madagascar's unique biodiversity, including its lemur populations, warrants investigation for arbovirus circulation.

Purpose of the Study:

• To investigate the epidemiological role of lemurs in arbovirus transmission in Madagascar.
• To determine the prevalence and distribution of arbovirus exposure in different lemur species and geographic locations.
• To assess the potential for lemurs to act as reservoirs or bridge hosts for arboviruses affecting humans.

Main Methods:

• Serological testing using hemagglutination inhibition (HAI) assays to detect antibodies against alphaviruses and flaviviruses.
• Analysis of mosquito fauna to identify species with lemur-biting preferences (lemurophilic).
• Correlation of serological data with lemur species and geographic origin.

Main Results:

• Lemur exposure to alphaviruses and flaviviruses varied significantly across Madagascar, ranging from 0% to 32% positive HAI tests.
• Specific lemur species and locations exhibited differential susceptibility and exposure levels.
• Evidence suggests shared arbovirus infections, particularly West Nile virus, between certain lemur species and humans, highlighting lemurs' potential epidemiological significance.

Conclusions:

• Lemurs play a demonstrable role in the circulation of arboviruses in Madagascar.
• The findings underscore the importance of considering lemurs in arbovirus surveillance and control strategies in the region.
• Further research is needed to evaluate lemur susceptibility to viruses like yellow fever, which is not yet endemic but poses a future risk.