What Is Nipah Virus and Should Pakistan Be Concerned?

News Desk

Islamabad: Reports of two new cases of the deadly Nipah virus in India have put health authorities across Asia on alert, prompting enhanced airport screening and surveillance measures to prevent cross-border spread. 

In Pakistan, the government has also issued a health advisory amid concerns about the possible entry of the virus.

The renewed focus has raised public questions about Nipah: what it is, how it spreads, and how serious the threat really is.

A Rare but Highly Fatal Virus

Nipah is a rare viral infection that primarily spreads from animals to humans, with fruit bats identified as its natural host. While some infections can be asymptomatic, the disease is often severe. 

The World Health Organisation (WHO) estimates its fatality rate to range between 40 and 75 percent, depending on how quickly cases are detected and treated.

Human-to-human transmission is possible but limited, and outbreaks tend to remain small and localized. 

According to the European Centre for Disease Prevention and Control, the virus does not spread easily between people. Several vaccine candidates are under development, but none has yet received regulatory approval.

Where Has Nipah Appeared Before?

The virus was first identified in Malaysia in 1999. Since then, small outbreaks have occurred almost every year, particularly in Bangladesh, with India also reporting sporadic cases.

The Coalition for Epidemic Preparedness Innovations (CEPI), which tracks emerging infectious threats, estimates that around 750 cases of Nipah have been recorded globally as of December, with 415 deaths. 

The virus’s spread and impact were documented in a 2023 Reuters investigative series titled Bat Lands.

How Does the Virus Spread?

Early outbreaks in Malaysia were largely linked to direct contact with infected pigs. More recent cases, however, have been traced to exposure to fruit bats, especially through contaminated food.

The WHO says the consumption of fruit or fruit products — notably raw date palm juice — contaminated with bat saliva or urine is the most common source of infection. 

Human-to-human transmission has also been documented, mainly among close contacts such as family members and caregivers.

Recognising the Symptoms

Initial symptoms of Nipah infection are non-specific and include fever, headache, and muscle pain, making early diagnosis difficult. As the disease progresses, patients may develop neurological complications such as acute encephalitis, an inflammation of the brain.

In severe cases, respiratory distress, seizures, and rapid progression to coma can occur within days. While many patients who survive make a full recovery, some experience long-term neurological problems.

How Big Is the Risk?

Health experts say that despite its high fatality rate, Nipah has not shown signs of becoming highly transmissible among humans or spreading widely across regions. Scientists also note that airport screening may have limited effectiveness due to the virus’s long incubation period.

Nonetheless, the WHO considers Nipah a major public health concern, particularly in countries where outbreaks recur. Beyond human health, the virus can also trigger economic consequences, including the mass culling of livestock such as pigs.

What’s in the Pipeline?

There are currently no approved vaccines or specific treatments for Nipah virus infection. However, several vaccine candidates are under development.

One of the most advanced is being developed by Oxford University researchers using the same platform as one of the Covid-19 vaccines. 

The candidate entered phase II clinical trials in Bangladesh in December, in collaboration with the International Centre for Diarrhoeal Disease Research, Bangladesh, and with funding from CEPI.

For now, public health experts stress that early detection, surveillance, and public awareness remain the most effective tools against the virus.