The World Health Organisation (WHO) has said the risk of the deadly Nipah virus spreading was low after three cases of infection were recently confirmed in India and Bangladesh. Nipah, which spreads from animals to humans, has no vaccine and a fatality rate ranging from 40 to 75 per cent, according to the UN health body.

“In the past few weeks, three cases of Nipah — two in India and one in Bangladesh — made headlines and caused concern about a wider outbreak,” WHO chief Tedros Adhanom Ghebreyesus told a press conference in Geneva on Wednesday.

WHO assessed the risk of spread of the Nipah virus regionally and globally and found it low, he added. Two cases of Nipah were confirmed last month in India’s West Bengal state, while one patient died in Bangladesh last week after contracting the virus.

“The two outbreaks were not related, although both occurred along the India-Bangladesh border, and share some of the same ecological and cultural conditions, as well as populations of the species of fruit bat that are known to be the natural reservoir of Nipah virus,” Tedros said.

Read More: WHO says one person dead from Nipah virus in Bangladesh

Nipah is a rare viral infection ‍that spreads largely from infected animals, mainly fruit bats, to humans. It can be asymptomatic, but it is often very dangerous, with a case fatality rate of 40% to 75%, depending on the ‌local healthcare system’s capacity for detection and ‍management, the WHO has said.

Symptoms include intense fever, vomiting and a respiratory infection, but severe cases can involve seizures and brain inflammation that results in a coma.

However, while it can also spread from person to person, ⁠it does not do this easily, and outbreaks ​are usually small and fairly contained, according to experts and the European Centre for Disease Prevention and Control. Candidate vaccines are under development, although none have been approved yet.

Nipah was first identified in 1998 after it spread among pig farmers in Malaysia. In India, the first Nipah outbreak was reported in West Bengal in 2001.

In 2018, at least 17 people died from Nipah in Kerala, and in 2023, two people died from the virus in the same southern Indian state.