Researchers from the National Centre for Biological Sciences (NCBS) and the National Institute for Mental Health and Neurosciences (NIMHANS) in Bengaluru have detected the first evidence of rabies virus in Indian bats.
The team of researchers, led by D. Pilot Dovih, a Ph.D student with Ecology and Evolution Department at NCBS, and Reeta S. Mani, Associate Professor, Department of Neurovirology, NIMHANS, isolated rabies neutralising antibodies in samples of fruit bats and insect bats from six villages in Nagaland. The samples were tested at NIMHANS, which is a WHO Collaborating Centre for reference and research on rabies.
While dog bites are the primary cause for death because of rabies in south Asia, incidents of contracting rabies from a bat bite have been reported in Western countries for decades, say the researchers.
“We have isolated antibodies in the blood, indicating that the bat may have been infected with the virus at some point in its life cycle. We could not isolate any virus or virus nucleic acid, which would confirm whether the bat had the virus at the time of death,” said Dr. Mani.
She added that there has been no systematic surveillance for detecting rabies, or any other pathogenic virus, in bats in India. The team carried out awareness programmes in the six villages to educate residents about the pathogens spread by bats, including Ebola and Nipah virus.
Villages in Nagaland were chosen for obtaining samples due to the traditional culture of bat harvesting in some parts of the State. Mr. Dovih said that lack of good hospitals and testing facilities in these villages meant that even when deaths were recorded, the cause of illness was seldom discovered.
“There was a disease outbreak in the late 1970s in a bat harvesting village, but there is no official documentation regarding the cause of the outbreak. Many residents migrated elsewhere during this outbreak,” said Mr. Dovih. Even today, residents from the villages surveyed report that at least two or three people in their late 20s to 30s die every year of unknown reasons.
However, Dr. Mani said it was too soon to sound an alarm bell. “One study should not affect the government’s focus as 99% of rabies cases is caused by dogs. We have a major problem with controlling rabies. We still carry one-third of the world rabies burden. That should be the priority,” she stressed, while pointing out that it is not as common for bats to come in contact with human beings.
