Nipah virus (NiV) infection is a newly emerging zoonosis that causes severe disease in both animals and humans. The natural host of the virus are fruit bats of the Pteropodidae family, Pteropus genus.

The three deaths that occurred over the past fortnight, were from the same family, including two siblings in their early twenties. The man who is undergoing treatment for 'Nipah' is the father of the two brothers who died.

A bat was found in the well of their house which has now been closed, the minister said.

A nursing assistant, Lini, who had treated three infected people, died on Monday morning.

However, it is yet to be confirmed if she had contracted the virus, which spreads through bats.

Five more people have died due to high fever and similar symptoms of the virus in Kozhikode and in neighbouring Malappuram district.

However, it is yet to be confirmed if their deaths were caused by the virus, health department sources said.

Shylaja and Labour minister, T P Ramakrishnan, who hails from Kozhikode, held discussions with officials and assured that the government had taken all necessary steps to prevent the spread of the virus, which has affected the state for the first time.

A high level team from the National Centre for Disease Control (NCDC) has already arrived in Kozhikode district to take stock of the situation.

The state has been put on high alert and two control rooms have also been opened in Kozhikode. The minister said there was no need to panic as the virus spreads only through direct contact with the infected person.

NiV was first identified during an outbreak of disease that took place in Kampung Sungai Nipah in Malaysia during 1998.

Then, pigs were the intermediate hosts. However, in subsequent NiV outbreaks, there were no intermediate hosts.

In Bangladesh in 2004, humans became infected with NiV as a result of consuming date palm sap that had been contaminated by infected fruit bats.