Containing a virus
How serious are the lion deaths in Gujarat?
A canine distemper virus (CDV) has led to many deaths in the Gir sanctuary. In September alone, 21 lions died. Every year, it is normal for 80-90 lions to die in Gujarat, according to wildlife experts. There is no number yet on how many have died this year, so we don’t know if there has been a spike.
Wildlife experts say that more than the numbers, it is the fear that mutation in a virus could have caused deaths that is perturbing. Scientists at the National Institute of Virology, Pune have confirmed the CDV virus in only five of the dead lions. But many more may have taken sick. Experts say that the virus may have jumped from dogs to lions.
What is Canine Distemper?
This is a viral disease that is frequent in dogs, foxes, wolves, big cats and even primates. It is caused by a single-stranded RNA virus of the family Paramyxoviridae (the family of viruses causing measles, mumps and bronchiolitis in humans). It infects the spinal cord and brain and also the respiratory and gastrointestinal tracts. The virus is believed to have a 50% fatality rate in dogs.
In 1994, the CDV was responsible for an epidemic in the Serengeti region of Africa, where 1,000 lions died in three weeks. Its prevalence in India has not been studied and only a few reports are available regarding its detection in wild carnivores.
How can the outbreak be checked?
The lion population should be immediately vaccinated with the available vaccine for CDV. At present, most of the available vaccines are made of CDV American genotypes 1 & 2. These have been used in a number of countries and found to be effective.
As the CDV is transmitted by airborne route as well as infected body secretions, healthy lions from the Gir forest ought to be shifted to an alternative suitable location. Moreover, as many of the Gir lions live outside protected areas and are in contact with domestic dwellings, their susceptibility to new pathogens has risen, according to scientists.
In 2013, the Supreme Court had called for shifting of some lions from Gujarat to Madhya Pradesh to “to save [them] from extinction, due to catastrophes like epidemic”. However, this is yet to happen.
Wildlife experts say vaccination is a bad idea as it could introduce new complications to the immune systems of the wild lions and make them vulnerable to unknown viruses.