BL Explainer. All you need to know about the Nipah outbreak

What is the Nipah virus?

Nipah is a zoonotic virus, transmitted when a person is in contact with an animal carrying the virus; consumes or handles food contaminated by it; or through close contact with a human carrying the infection. So healthcare workers and care-givers are at risk.

A known natural reservoir for the virus is the bat family — the Pteropus bat species (popular as the fruit bat or flying fox). Epidemiologists clarify, of 1,00,000 bats only four or five could be carrying the Nipah virus. And shedding of the virus in secretions is not uniform — so it takes a lot of things coming together for a virus to jump species.

In the first recognised outbreak in Malaysia (that also affected Singapore), the infection came from direct contact with sick pigs or contaminated tissue. Later infections in Bangladesh and India are said to have been from the consumption of fruits, fruit products (raw date palm juice) contaminated with the urine or saliva from infected fruit bats, according to the World Health Organization.

Why is it in news now?

Two deaths from Nipah have been reported in India, from Kerala. About six people are infected according to reports on Friday.

But India is no stranger to Nipah, with recent outbreaks in 2018 and 2021.

What is the mortality and contagion risk in this virus?

The Nipah virus must be contained, given its high mortality rate. The infection can lead to acute respiratory distress, encephalitis, and/or seizures, and can progress to coma within 24 to 48 hours.

The case fatality rate is estimated at 40- 75 per cent, the WHO said, although this could vary depending on local capabilities for epidemiological surveillance and clinical management.

What are the common treatments for the infection?

Those infected by the Nipah virus are treated with supportive care, as there is no primary treatment or vaccine available for people or animals. Immunological and drug therapies are said to be under development.

But there are simple ways to prevent and contain transmission of infection — including staying away from (and not destroying) bat habitats; not consuming half-bitten fruits and maintaining hygiene standards — including boiling freshly collected date palm juice, washing and peeling these fruits before consumption. Hygienic agricultural practices involving the handling of pigs and goats, for example in farms help keep the virus at bay.

What is the risk of the virus spreading all over India?

Kerala has been internationally recognised for its adept handling and containing of Nipah in 2018. The political establishment at the State and the Centre, and work by the doctors and supportive healthcare ecosystem helped contain the infection within a month since it was first reported, mid-May.

This time too, similar efforts are underway. Doctors and the surveillance infrastructure in the country need to be alert for similar symptoms, say epidemiologists, as surveillance is intensified in neighbouring States. .

What are the Centre and Kerala government doing about it?

The Centre has sent teams to Kerala to take steps required to contain the virus, and samples have been sent to National Institute of Virology (Pune). The Kerala government has set up containment zones in Kozhikode, where the infections were first diagnosed, contact tracing (of people the infected may have been in touch with) has been undertaken and educational institutions have been shut, as a preventive action.

Are the measures taken by the government enough?

Details are awaited from the sample tests, as it would help direct, intensify and streamline public health interventions from State and Centre.