Following two confirmed Nipah virus infections in West Bengal in India at the end of January, several media outlets reported that countries instituted airport screening measures over concerns the outbreak could spread. It has now been confirmed that one of the infected cases died, while the other recovered and was discharged in February. This was followed by another fatal case in Bangladesh in February, although the cases are unrelated.  The risk of Nipah virus infection for people in the UK is extremely low at the moment.

Nipah virus is officially listed as a priority pathogen by the World Health Organization (WHO) and has pandemic potential, so much so that the 2011 film Contagion, which depicts a fast-spreading global virus, was partly inspired by it. So we asked London School of Hygiene & Tropical Medicine expert Ms Sol Kim, who is a PhD student jointly at LSHTM and Nagasaki University studying Nipah virus epidemiology and dynamics, whether we should be worried.

What is the Nipah virus?

Nipah virus is an RNA virus in the Paramyxoviridae family and naturally found in fruit bats (flying foxes), which live across South and Southeast Asia. As a natural host, they can carry the virus without getting sick and pass it to other animals, including humans, through saliva, urine, or faeces.

The virus was first identified in 1998 during an outbreak involving pigs and pig farmers in Malaysia. In 1999, Singapore also had an outbreak linked to imported pigs, though there have been no further outbreaks in either country since.

India and Bangladesh reported outbreaks starting in 2001, with Bangladesh reporting outbreaks almost every year since. In India, outbreaks are less frequent, though the state of Kerala has seen more repeated events since 2018.

How do people get infected with Nipah?

People can catch Nipah by coming into contact with bat bodily fluids or things contaminated by them. The most common is the consumption of raw date palm sap (juice), as the fruit bats can contaminate the sap or the collection containers while feeding or excreting.

If someone drinks sap containing the virus, there’s a chance they may get infected. This is called a ‘spillover event’, meaning that the virus has jumped from one species to another. This can happen in other ways (for example direct contact with bats or other infected animals like pigs) but in past Nipah virus outbreaks, date palm sap has been the most well-known and repeatedly documented route.

Importantly, person-to-person transmission can follow a spillover event, potentially leading to a wider outbreak in humans. However, this usually requires close and prolonged contact with an infected person, especially exposure to infected bodily fluids.

Why is Nipah considered so dangerous?

When infected with Nipah virus, people can develop fever and respiratory symptoms such as cough and difficulty breathing, and in worse cases, brain infection (encephalitis) and neurological symptoms.

The infection carries a high risk of death - known as a case fatality ratio - of 45% to 75% which is very high and dangerous. This is why Nipah is taken very seriously by national public health institutes and the WHO. However, the number of cases is usually very small, and globally it has remained rare. Sadly, for those who are infected there is no licensed specific treatment yet and care is mainly supportive.

Why is Nipah virus considered a priority pathogen for pandemic preparedness by the WHO?

In 2024, the WHO announced its list of priority pathogens for scientific research for epidemic and pandemic preparedness, including the Nipah virus family.

One of the reasons Nipah was included is due to its genetic structure as an RNA virus, which can mutate over time and become more transmissible among people. For now, Nipah does not spread easily between people in everyday settings, and for a large epidemic or pandemic, you would typically need more efficient and consistent person-to-person transmission.

Another reason is ecology: as habitats change, fruit bats are overlapping more with humans. Deforestation, agricultural expansion, and climate pressures can increase chances of bat-human contact. That doesn’t mean 'bats are to blame' as they are part of the ecosystem - the real issue is how human and other animal environments intersect.

Could a Nipah outbreak spark the next pandemic? What would need to happen?

The current epidemiology suggests a low chance of Nipah turning into a global pandemic at this time. These outbreaks in early 2026 are small and were effectively contained. Local health authorities in affected regions have built a lot of experience over the last two decades, and that matters.

It’s hard to predict which pathogen will cause the next pandemic. What we do know is that outbreaks will keep happening, and because our world is so connected through travel and trade, viruses can potentially spread cross-border quickly. The goal of preparedness is to reduce both the chance of spread and the impact when something does happen.

How are scientists doing in developing tests, containment and treatment or vaccines?

The good news is that there has been real progress for Nipah. There are multiple therapeutics and vaccine candidates under development. Recently, one vaccine candidate developed by the University of Oxford moved into a Phase 2 clinical trial in Bangladesh, and the programme has also been discussed in the context of accelerated regulatory pathways.

Is there anything society can do to make sure Nipah never becomes a global pandemic?

“Never” is a hard promise in public health. But we can absolutely reduce risk.

With ongoing advances in vaccines, therapeutics, and diagnostics, Nipah control is becoming more feasible than previously thought. This should remind us exactly what pandemic preparedness is for: investing in tools before the crisis, not during it. This ‘in-between’ period is when countries and agencies need to coordinate on surveillance, lab capacity, infection control, and clinical trial readiness.

If people are concerned about Nipah, what can they do to keep themselves or their loved ones safe?

Finding out health information from trustworthy sources is key – the UK Health Security Agency recently published a really helpful blog on how Nipah spreads and what to do if you are concerned.

In general, if you’re travelling to places where a Nipah outbreak has occurred, the idea is mainly to reduce exposure and follow basic hygiene guidelines; wash your hands, and avoid direct, unprotected contact with someone who is unwell.

If you are interested in learning more about infectious diseases and how they spread, consider signing up to LSHTM’s short courses; Introduction to Infectious Disease Modelling and Its Applications and Infectious Disease 'Omics.

If you’d like to study a full MSc course at LSHTM, join our upcoming Virtual Open Days (3-5 March) where you can attend live webinars and Q&A sessions with our programme directors, current students and student services to find out what makes LSHTM a leader in global health education.