Brain-swelling, respiratory failure: 5 reasons scientists are terrified of the new Nipah virus outbreak
By Ascah Mwango, January 31, 2026A fresh outbreak of the Nipah virus in India has pushed health authorities in Asia to act fast. The virus is not new, but according to the World Health Organisation, its effects are severe and unpredictable, and that is why scientists are watching it closely.
Here are five reasons why experts are concerned:
1. It can cause deadly brain swelling
One of the most frightening effects of Nipah is encephalitis, which is a dangerous swelling of the brain.
At the beginning, a patient may look like they have a normal fever. But in some cases, the infection quickly moves to the brain and confuses, severe headaches, seizures, loss of consciousness, and coma.
Once the brain is affected, the condition can worsen very fast. Doctors often have little time to stop the damage.
2. It can lead to respiratory failure
Nipah not only attack the brain. It also attacks the lungs and breathing system.
Some patients develop serious breathing problems such as shortness of breath, chest tightness, pneumonia-like symptoms, and low oxygen levels.
In severe cases, the lungs fail, and the patient needs oxygen support or a ventilator. This is one reason Nipah is terrifying: it can shut down the body in more than one way.
3. There is no approved cure or vaccine
This is a major reason scientists fear Nipah outbreaks.
At the moment, no approved medicine kills the Nipah virus in the body. There is also no widely available vaccine for the public.
What hospitals can do is supportive care, like controlling fever and pain, giving fluids, helping the patient breathe, and treating complications.
Supportive care can save lives, but it does not guarantee recovery, especially in severe cases.
4. The death rate is extremely high
Nipah is known for its high fatality rate. In past outbreaks, the percentage of people who died has been very high compared to many other viral diseases.
Health experts estimate that the fatality rate can range between 40% and 75%, depending on the outbreak, the health system response, and how early patients get care.
That means even a small outbreak can become a national emergency.
5. It can spread from animals to humans, and also between people
Nipah is a zoonotic virus. This means it can spread from animals to humans.
The virus is linked to fruit bats, and people can get infected through food contaminated by bats, contact with infected animals like pigs, and handling sick animals or animal waste.
The bigger worry is that Nipah can also spread from person to person, especially through close contact with an infected person’s body fluids.
This is why hospitals and caregivers are at risk during outbreaks. If the virus spreads inside a family or health facility, the outbreak can expand quickly.
Scientists fear that if Nipah ever changes and becomes easier to spread between people, controlling it would become much harder.
However, it is worth noting that Nipah does not spread as easily as some common viruses. That is one reason experts often say the global risk is low for now.
The World Health Organisation said on Friday that the chances of the Nipah virus spreading remain low, noting that none of the more than 190 people who came into contact with the two infected patients in India have tested positive or shown any symptoms.
Several Asian destinations, including Hong Kong, Malaysia, Singapore, Thailand and Vietnam, have stepped up airport screening measures this week after India confirmed the infections, as authorities move to prevent any possible cross-border spread.
“The risk on a national, regional and global level is considered low,” Anais Legand, an official with WHO’s Health Emergencies Programme, said, adding that neither of the patients travelled while they were showing symptoms.
Both patients are currently hospitalised and are alive, she said, with one of them showing signs of improvement.