The Gir National Park in the western Indian state of Gujarat is the last remaining natural habitat of Asiatic lions, whose numbers have risen from 627 to 891 in five years, according to a 2025 census, reflecting conservation success even as new risks emerge.

The recent string of deaths may be linked to babesiosis, a tick-borne parasitic disease, said Arjun Modhwadia, the state's forest and environment minister, citing preliminary findings and cautioning that laboratory confirmation is awaited.

"The exact cause will be confirmed after analysis, but initial indications point towards babesiosis," he told reporters in Gandhinagar city.

Most of the deaths were reported in areas outside the protected wildlife sanctuary, signalling a possible infectious outbreak spreading among lions that increasingly roam beyond forest boundaries.

Samples from the cubs have been sent to a research centre, while specialist teams have been deployed to assist in surveillance and containment.

Authorities have also stepped up preventive measures, the minister said, including isolating lions within a 10-kilometre (six-mile) radius of affected zones and launching large-scale "deticking" drives.

Babesiosis, commonly transmitted through tick bites, attacks red blood cells and can cause weakness, fever and death, with cubs particularly vulnerable due to lower immunity.

In 2018, a disease outbreak in Gir killed 11 lions. It was later attributed to a combination of canine distemper virus (CDV) and babesiosis.

Recently, a tigress and its four cubs died in quick succession in Madhya Pradesh state's Kanha reserve, with local media reports saying the cause may have been CDV.

CDV is highly contagious and passes from dogs through respiratory droplets, saliva and close contact.