Nipah Virus alert sounded in Kerala: What is it and what are its symptoms?


The health department of the southern Indian state of Kerala sounded an alert in the Kozhikode district on Monday after two “unnatural deaths” at a private hospital were suspected to be caused by Nipah Virus (NiV), reported Indian media.

State health minister Veena George called a high-level meeting to assess the situation. Relatives of one of the deceased have been admitted to a hospital’s intensive care unit.

What is Nipah Virus?

According to the World Health Organization (WHO), the Nipah Virus infection is a zoonotic illness, which means that it is transmitted from animals to humans. The infection can also spread through contaminated food or directly from an infected person to another person.

The virus has caused only a few known outbreaks in Asia but it infects a range of animals including pigs and bats.

The first Nipah virus outbreak was reported in Malaysia in 1999 when the virus infected pig farmers. No such outbreak has been reported in the country since then. However, the virus was detected in Bangladesh in 2001 and has been identified in eastern India too.

How does it spread?

Fruit bats, who belong to the Pteropodidae family, are the natural host of the Nipah virus. However, during the 1999 Malaysian outbreak, the virus was detected in other domestic animals such as horses, sheep, cats, goats, and pigs. At the time, most human infections occurred due to direct contact with infected pigs or their contaminated tissues.

The virus is highly contagious in pigs and can be transmitted from them to humans. It can also spread from human to human through unprotected direct physical contact with an infected person or with infected animals or their body fluids such as blood, urine or saliva.


Nipah virus infection in humans can be asymptomatic or cause seizures, respiratory infections, and fatal encephalitis. People who contract the virus initially experience fever, myalgia, headaches, sore throat, and vomiting. These can be followed by other symptoms such as altered consciousness, drowsiness, dizziness, and neurological signs indicating encephalitis.

In some patients, the infection can result in atypical pneumonia and severe respiratory problems like respiratory distress. Encephalitis and seizures have been seen in severe cases where they can progress to coma within 24 to 48 hours.

The incubation period of the virus is from 4 to 14 days but has also been as long as 45 days in a case.

The fatality rate of Nipah virus infection ranges between 40% and 75%. It can vary depending on the surveillance and health system in the affected area during an outbreak.

No vaccine or drugs have been developed yet to treat Nipah virus infection.


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