The Indian Council for Medical Research (ICMR) has confirmed that the Canine Distemper Virus (CDV) was responsible for lion deaths in the Gir forest of Gujarat and recommended that the remaining lions be vaccinated to prevent further outbreaks. This goes against recommendations by wildlife biologists that wild animals shouldn’t be vaccinated.
“The scientists of ICMR-NIV (ICMR-National Institute of Virology) have recommended the existing CDV vaccine which should work as a protective intervention for Gir lions,” said a press statement on Friday from the institute.
Though 21 lions reportedly died between September and October, the Pune-based ICMR-NIV found CDV responsible for the death of 5 Asiatic lions in Gir. The genetic sequence of the virus was compared to available CDV sequences and it was found to be related to the East African strains.
“It would be stupid to vaccinate wild lions because it’s likely to compromise their immunity against future infections. These are wild animals and not ones in a zoo,” Y.S. Jhala, a senior scientist at the Wildlife Institute of India had told The Hindu on Thursday.
An anonymous ICMR official said administering a vaccine at best, could protect unaffected animals.
“We routinely administer vaccines to humans. So I don’t see why wild animals’ immune systems should behave very differently,” the person said in a phone conversation. However, the NIV was yet to determine if the vaccine, currently available to treat CDV, matched the strain of the virus circulating in the lions. This matching determines the efficacy of the vaccine.
CDV causes a highly contagious and life-threatening disease in dogs. It also affects different wild carnivores viz., wolves, foxes, raccoons, red pandas, ferrets, hyenas, tigers, and lions. The prevalence of this virus and its diversity in wildlife of India has not been studied. Only a few reports are available regarding the detection of CDV in captive wild carnivores which included tigers and red pandas. A report in 2016 from Etawah, Uttar Pradesh about CDV infection was confirmed by the Indian Veterinary Research Institute. There dogs were considered to be the primary source of infection and virus transmission, the ICMR added.
In the past, CDV had wiped out 30% of the total population of lions in Serengeti forest areas in East Africa. Considering the threat posed by CDV, ICMR has requested the Government of India to take immediate steps to save the Gir lions, which are heading towards extinction. As a precautionary measure, 300 shots of CDV vaccine have been imported from the U.S.. ICMR has also recommended that the animals should be placed in 2-3 different sanctuaries.