Survey for bat lyssaviruses, Thailand

Area of Science:

• Virology
• Zoonotic Diseases
• Bat Ecology

Background:

• Lyssaviruses are a significant public health concern, primarily known for causing rabies.
• Bat populations are known reservoirs for various lyssaviruses, necessitating surveillance in endemic regions.
• Understanding lyssavirus diversity in bats is crucial for assessing zoonotic risk.

Purpose of the Study:

• To conduct surveillance for lyssaviruses in bat populations across 8 provinces in Thailand.
• To identify the presence of neutralizing antibodies against known lyssaviruses in collected bat sera.
• To investigate potential novel lyssavirus genotypes circulating in Thai bats.

Main Methods:

• Serum samples were collected from 932 bats of 11 species captured in Thailand between 2002 and 2003.
• Virus neutralization assays were performed on 394 suitable serum samples to detect lyssavirus antibodies.
• Antibody presence was tested against rabies virus and other specific lyssaviruses (Aravan, Khujand, Irkut, Australian bat lyssavirus).

Main Results:

• No bat serum samples exhibited neutralizing antibodies against rabies virus.
• Sixteen serum samples showed detectable neutralizing antibodies against Aravan virus, Khujand virus, Irkut virus, or Australian bat lyssavirus.
• These positive results were primarily associated with fruit bats, specifically Pteropus lylei (15 samples) and Eonycteris spelaea (1 sample).

Conclusions:

• The findings indicate the presence of lyssaviruses, distinct from classical rabies virus, in Thai bat populations.
• The identified antibodies suggest circulation of viruses related to novel lyssavirus genotypes.
• Continued surveillance is warranted to fully characterize these putative lyssavirus genotypes and their zoonotic potential.