At least four people have died in the state of Kerala, India, after contracting the Nipah Virus over the past fortnight. There have been other suspected but unconfirmed cases of people being hospitalized with symptoms of the infection in the Kozhikode district in Kerala. 

Government authorities are focused on efforts to contain the threat of a possible outbreak of the deadly virus, with potential plans to involve the World Health Organization (WHO).

“We have sent blood and body fluid samples of all suspected cases for confirmation to National Institute of Virology in Pune. So far, we got confirmation that three deaths were because of Nipah,” said Rajeev Sadanandan, health secretary of Kerala. “We are now concentrating on precautions to prevent the spread of the disease since the treatment is limited to supportive care.”

What do we know about the Nipah Virus (NiV)?

NiV is classified as a zoonosis, which means the disease can be transmitted from animals to human beings. According to WHO, fruit bats are regarded the natural host of the virus. 

The virus was first identified in 1999 during an outbreak of encephalitis and respiratory illness in Malaysia and Singapore, primarily affecting pig farmers. More than 300 human cases were recorded with over a 100 deaths. As a result, almost a million pigs were euthanized in efforts to control the outbreak.

How deadly is the virus and what are the symptoms?

After exposure to the virus, the illness may present itself with symptoms such as fever and headache for 3-14 days followed by drowsiness, disorientation, and mental confusion, according to the  Centers for Disease Control and Prevention (CDC). The infected person may fall into a coma within 48 hours after showing severe symptoms such as acute respiratory syndrome.

Intensive supportive care is the primary treatment for human cases. Currently, no vaccination is available (for humans nor animals) to treat NiV, which has a fatality rate of 70 to 75 percent. The virus causes an inflammation of the brain known as encephalitis which can be lethal.

How did NiV begin infecting people in Kerala?

According to health officials from the state, mangoes bitten by fruit bats were found in the house of the three people who died of NiV. The virus was suspected to have spread to a fourth victim — a nurse who worked at the Taluk Hospital in Perambra town, and took care of one of the victims of Nipah fever.

While this is the first case of the virus spreading in Kerala, outbreaks have occurred before in India. Previously, two Nipah outbreaks occurred in the state of West Bengal. The first in Siliguri during 2001, which resulted in 45 deaths and a second in the Nadia district during 2007, which led to five deaths.

According to a WHO report on the geographic distribution of the virus, parts of Asia, Australia, Madagascar, and Ghana may also be at risk of outbreaks.