Nipah virus: this is how far we are with vaccine development

The images feel uncomfortably familiar. Thermal scanners are reappearing at airports in Asia. Travelers are being checked for fever. Videos circulating on social media immediately bring back memories of the early days of the coronavirus pandemic. However, the cause is not a new coronavirus variant, but the Nipah virus. This virus is emerging in parts of India and Bangladesh. The virus has an extremely high mortality rate. While the world watches vigilantly, a quiet revolution in biotechnology is taking place in the background. Scientists are not sitting idly by waiting for things to go wrong.

Not a new player

The Nipah virus is not a new player on the world stage. We have known about it since a major outbreak in Malaysia in 1998. What makes this virus so terrifying is the brutal effectiveness with which it strikes. The mortality rates speak for themselves. Between 40 and 75 percent of infected people do not survive the infection. That is many times more deadly than COVID-19.

The symptoms often start deceptively simple. Patients complain of headaches, fever, and breathing problems. However, this can quickly escalate to severe brain inflammation.

No approved vaccine

Until recently, doctors were left empty-handed. There was no approved vaccine available. There was no specific treatment that could stop the virus. The virus lurks in nature in certain bat populations. These flying dogs carry the virus without becoming ill themselves. Through their feces or saliva, they contaminate fruit or date palm juice. Animals that eat this, such as pigs, then form an intermediate link to humans. This chain of infection makes the virus unpredictable.

Oxford takes the lead

In 2026, we are in a very different position than we were a few years ago. Science has made enormous strides. A crucial milestone was reached at the end of 2025. In December, the University of Oxford launched the world's first Phase II clinical trial of a Nipah vaccine.

The trial is taking place in Bangladesh, precisely in the area where the virus regularly strikes. Researchers are testing the vaccine, called ChAdOx1 NipahB, on 306 healthy participants. The focus is on safety and the response of the immune system.

It is a world-class collaboration. Oxford is working with local partners and receiving support from the Coalition for Epidemic Preparedness Innovations (CEPI). Previous tests in Oxford, known as Phase I studies, have already been successfully completed. The results showed that the vaccine is safe for humans. We are now waiting for the final data from Bangladesh. If this trial is successful, we will have a working weapon against this deadly enemy for the first time.

Why this is (probably) not going to be a pandemic

The fear of a new global lockdown is understandable. However, from a scientific point of view, this fear is less justified in the case of Nipah. The spread of this virus is fundamentally different from that of influenza or coronavirus. The Nipah virus is not extremely contagious through the air over long distances. The primary route of transmission is through direct contact with infected animals or their bodily fluids. Drinking contaminated, raw date palm juice is also a known source of infection in South Asia.

Human-to-human transmission does occur, but this usually only happens through very close contact, such as family members caring for a sick person or healthcare workers without protection. The RIVM emphasizes that the virus spreads less quickly than COVID-19. As a result, outbreaks often remain localized. Nevertheless, the World Health Organization (WHO) has placed the virus high on its list of priorities. A mutation could increase its transmissibility. That risk, combined with its high mortality rate, compels us to remain vigilant.