Nipah virus (NiV) is an emerging zoonotic virus that can be transmitted to humans from animals (both wild and domestic).

Fruit bats of the Pteropodidae family are the natural hosts of Nipah virus. NiV infection can be asymptomatic or mild (subclinical), but it also causes acute respiratory illness and fatal encephalitis.

Many paramyxoviruses are host-specific, and several are pathogenic to humans, including NiV, measles virus, mumps virus, Hendra virus (HeV), and several parainfluenza viruses.

Symptoms:

Initial symptoms of NiV infection may include fever, headache, myalgia (muscle pain), nausea, vomiting, sore throat, cough and/or respiratory discomfort. In severe cases, encephalitis and seizures occur and may lead to coma within 24–48 hours.

Most people who survive encephalitis make a full recovery, but neurological dysfunctions remain in around 20% of survivors.

NiV has caused a few known outbreaks in Asia. It emerged in 1998 during an outbreak among pig farmers in the village of Sungai Nipah in Malaysia.

In the southern Indian state of Kerala, the bat-borne Nipah virus has infected six people — two of whom have died — since it emerged in late August.

More than 700 people, including health-care workers, have been tested for infection over the past week. State authorities have closed some schools, offices and public-transport networks.

There are currently no drugs or vaccines specific for Nipah virus infection although WHO has identified Nipah as a priority disease for the WHO Research and Development Blueprint.

Intensive supportive care is recommended to treat severe respiratory and neurologic complications.