Nipah virus kills 9 in Kerala: All you need to know about the rare and deadly NiV carried by fruit bats

After over a decade, the rare Nipah virus has struck India, and this time in Kerala's Kozhikode district, by claiming nine lives. The virus, known to have nearly 70 percent mortality rate has drawn a sharp reaction from both from the state as well as the Union Ministry of Health, with health minister JP Nadda directing the Director of National Centre for Disease Control (NCDC) to visit Kerala's Kozhikode district to assist the state government in the wake of death.

To help you prepare better in implementing safeguards against the infection, the following is all we know about the disease so far:

What is Nipah virus (NiV)?

According to World Health Organisation, Nipah virus (NiV) infection is a newly emerging zoonosis (a disease which can be transmitted to humans from animals) that causes severe disease in both animals and humans. The natural host of the virus are fruit bats of the Pteropodidae Family, Pteropus genus (fruit-eating species, popularly known as flying foxes).

Who are in danger?

NiV affects humans as well as pigs and other domestic animals.

What are the symptoms of NiV infection?

According to the WHO, the symptoms of NiV infection in humans has a range of clinical presentations, from asymptomatic infection to acute respiratory syndrome and fatal encephalitis.

When was Nipah virus first identified?

NiV was first identified during an outbreak of disease that took place in Kampung Sungai Nipah, Malaysia in 1998. According to WHO, pigs were intermediate hosts, however, no intermediate hosts were found in subsequent NiV outbreaks.

 Nipah virus kills 9 in Kerala: All you need to know about the rare and deadly NiV carried by fruit bats

Geographical spread of Nipah virus. Image courtesy: WHO

According to a 2013 ICMR-sponsored research paper, "the outbreak started in the pig farmers near Ipoh in the Kinta District of Perak, some 200 kilometres north of Kuala Lumpur and spread to three other major pig-rearing areas (the largest in Southeast Asia) in Negeri Sembilan and Sungei Buloh in Selangor. The disease was named after Kampung Sungai Nipah (Nipah River Village), where the first viral isolate was obtained and therefore named as NiV".

Total 265 cases were reported of which 105 died. Around 1.1 million pigs had to be destroyed to control the outbreak, the report adds.

How does NiV transmit?

According to the report, in Malaysia and Singapore, NiV transmitted to humans through infected pigs. However, during the NIV outbreaks in India and Bangladesh, the disease transmitted "directly from bats to human followed by a human to human" and "the drinking of raw date palm sap contaminated with fruit bat urine or saliva containing NiV is the only known cause of outbreak" of the disease in Bangladesh outbreaks."

When was the first NiV outbreak observed in India?

The first NiV outbreak in India was observed in 2001 in Siliguri, West Bengal. Though the agent for the outbreak was not known, analysis of the limited sequence data suggested that the NiV strains associated with the outbreak were more closely related to NiV isolated in Bangladesh than to NiV isolated in Malaysia. According to some, Siliguri's proximity to Bangladesh, which had been seeing recurrent cases of NiV infection from 2001 through 2013 could have been behind it.

A second infection had reportedly emerged in Nadia district, again close to the border with Bangladesh in 2007.

The outbreak of NiV in Kerala is the latest and third such incident, according to reports.

Is there a vaccine for NiV infection?

No. According to WHO, there is no vaccine for either humans or animals. The only treatment available for NiV infection is intensive supportive care.

What precautions to take?

Contact with bats saliva or urine either via a contaminated item (like palm sap or fruit dropped from a tree) or via animals contaminated by the virus (such as pigs or other livestock animals) or humans already infected with NiV are considered to be the prime reason for NiV infection. If NiV is endemic to your area, it's best to avoid areas that bats inhabitate.

Updated Date: May 21, 2018 13:50:11 IST