A deadly viral outbreak among lions in Gujarat’s Gir forest has prompted wildlife scientists to blame what some say is a “collective national failure” to provide the big cats a second home even after a Supreme Court directive.

At least 11 lions among 23 found dead in the Gir forest over the past month have died from canine distemper virus (CDV) and protozoal infections, Gujarat state officials said on Wednesday.

The condition of three among 36 other lions under observation is critical, they said.

Gujarat’s forest and environment minister Ganpat Vasava said CDV had been found in samples of four lions by the Pune-based National Institute of Virology.

Protozoal infections were found in samples from the other seven lions. Infections with CDV lower immunity, making lions susceptible to protozoal infections.

The confirmation of a viral outbreak and infections comes weeks after forest officials attributed the deaths to infighting among the lions.

State officials said they had ordered 300 shots of a vaccine from the US to protect the lions. The vaccines will be administered, if needed, to the 36 lions now under observation, Rajeev Kumar Gupta, a state forest official, said.

A 2015 census had determined that Gir was home to 523 lions: 109 males, 201 females, 73 sub-adults and 140 cubs.

Conservation biologists point out that the canine distemper virus had caused the deaths of over 1,000 lions in the Serengeti National Park in Tanzania in 1994 — nearly one-third of the park’s lion population.

They say viral outbreaks had been a key concern driving the long-standing demand to relocate some Gir lions to another site.

Wildlife scientists, concerned that all of the Asiatic lions are clustered in a single forest, have for more than

two decades argued for relocating some lions to the Kuno national park in Madhya Pradesh.

The Madhya Pradesh forest department had between 2000 and 2005 cleared several villages in the Kuno forest area, rehabilitating residents to make space for the introduction of lions from Gir.

But Gujarat has refused to release its lions.

The Supreme Court had in April 2013, responding to a petition by an environmental group, directed the Union environment and forests ministry to take “urgent steps” to bring some lions from Gir into Kuno.

The court had observed that the ministry’s decision to introduce lions in Kuno was of “utmost importance” to preserve the Asiatic lion. It had also directed that the order should be carried out “in letter and spirit” within six months.

“But nothing has happened — Gujarat has still not released its lions, this is our collective national failure,” Ravi Chellam, a Bangalore-based conservation biologist who has studied Gir lions since the late 1980s, told The Telegraph. “We should all be held guilty of contempt of court.”

The Supreme Court on Wednesday asked the Centre to probe the deaths of the 23 lions.

A bench, hearing a matter related to an unrelated proposal to reintroduce cheetahs into India from Namibia, heard about the implications of a viral outbreak.

“If there is any kind of virus infection, all lions could be wiped out from the area,” Ritwick Dutta, environmental lawyer, told the bench.