The Zoological Survey of India (ZSI) has identified 23 species of blood-sucking flies belonging to the Culicoides genus in the Andaman and Nicobar Islands, with 13 of them being reported for the first time in India.

Known locally as “Bhusi flies,” these tiny insects, though similar in appearance to flies, are more closely related to mosquitoes in their feeding habits. They primarily feed on the blood of livestock such as sheep, goats, cattle, and wild animals like deer.

Of particular concern are the five species known to transmit the Blue Tongue Disease virus, a condition that can be fatal to livestock, potentially causing significant economic losses to the animal husbandry sector.

Dr Dhriti Banerjee, ZSI Director, said, “The presence of multiple Culicoides species, particularly those responsible for Blue Tongue virus transmission, necessitates regular surveillance and appropriate control measures in the Andaman and Nicobar Islands. This is especially crucial given the region’s importance as a major tourist destination.”

The study, conducted in 2022 and 2023, revealed that 17 of the 23 species identified are known to bite humans, though researchers reassure that no transmissions in human beings have been reported so far.

Dr Atanu Naskar, Officer-in-Charge of ZSI’s Diptera section, said a systematic survey of the entire archipelago is required to understand the role of these insects in disease transmission.

Senior Research Fellow Kaustav Mukherjee, one of the researchers involved in the study, said, “We expect to discover more Culicoides species as we continue our survey. Additionally, we are conducting population and genetic studies of these flies.”

Blue Tongue Disease, transmitted by these flies, manifests through symptoms such as blue discoloration of the tongue, fever, facial swelling, and excessive salivation, potentially leading to death in affected animals.