8 years after deadly CDV outbreak, Gujarat’s lion vaccine is still work in progress

Ahmedabad: After the recent deaths of 10 cubs and three adult lions raised fears of the possible return of the canine distemper virus (CDV) to Gujarat, questions are emerging on the still undelivered indigenous CDV vaccine promised in 2018. The state had vowed to develop the vaccine after the devastating 2018 outbreak, which killed more than two dozen lions, with CDV and babesiosis infections identified as the primary causes. The outbreak forced the forest department to import emergency vaccine doses from the United States and vaccinate captive lions while scientists searched for a long-term solution. In the aftermath of the outbreak, the Gujarat Biotechnology Research Centre (GBRC) was tasked with developing an indigenous vaccine tailored to the CDV strain affecting Gir lions. A senior forest department officer said it was revealed that the virus circulating among the lions in the state differed by about 6% from the strains used in available vaccines, prompting the need for a locally developed formulation. A former principal chief conservator of forests, requesting anonymity, said that in 2020, state officials announced that the vaccine was under development and had reached the trial stage. He said it was indicated that the indigenous formulation could potentially be administered as a single shot, unlike imported vaccines, which required multiple doses. Two years later, in March 2022, the Gujarat govt informed the state assembly that GBRC had completed formulation development and that clinical trials were underway. The officer said that in May 2022, further progress was reported. State science and technology officials said vaccine trials on laboratory animals had been completed successfully, and permissions were being sought to test on larger felines, possibly leopards, before eventual use on lions. Officials also revealed that an Ahmedabad-based biotechnology company had been associated with vaccine development and that the Covid-19 pandemic had slowed some aspects of the programme. “Since then, there has been no communication on the vaccine either from the forest department or the GBRC,” the officer said. The last officially available progress reports from the GBRC indicate that work on the vaccine continued through 2023-24. Annual reports for the year 2023-24 mention ‘Development of inactivated canine distemper virus vaccine of the strain isolated from Asiatic lions of Gujarat, India’ funded by the Centre’s department of science and technology. The fund granted was Rs 54.3 lakh, and the project duration was two years. The report stated that “...the GBRC performs diagnosis of CDV by RT-PCR with samples from suspected cases and dead lions. In the year 2023-24, 26 samples were screened, of which four were found positive for CDV.” Wildlife experts point out that nearly eight years after the outbreak that triggered the project, Gujarat still does not have an approved indigenous CDV vaccine for its lion population. Unconfirmed reports on the recent lion deaths suggest a possible combination of CDV and babesiosis infection, recalling the pattern seen in 2018. Forest department officials have sent samples for testing and are awaiting final confirmation from laboratories. Jaipal Singh, the principal chief conservator of forests (wildlife), and forest and environment minister Arjun Modhvadia were not available for comment.