The Nipah virus, first identified in a Malaysian village, is a highly fatal infectious disease primarily transmitted by fruit bats, though pigs and other animals can also act as hosts. Recent cases in northeastern India and Bangladesh in early 2026 have reignited concerns about its potential for wider spread, prompting Thailand, Malaysia, and Singapore to strengthen border controls.
According to Tedros Adhanom Ghebreyesus, the two recent clusters in India and Bangladesh are unrelated, and after tracing over 230 contacts, no additional cases have been detected. The WHO currently assesses the risk of regional or global spread as “low.”
In India, a nurse in West Bengal who contracted the virus in December 2025 recently died from cardiac arrest, highlighting the virus’s severity. Nipah infection can cause fever, chills, sore throat, vomiting, and in severe cases, neurological complications such as encephalitis, seizures, or comas, as well as acute respiratory failure. Fatality rates range between 40 and 75 percent, with around 20 percent of survivors experiencing lasting neurological effects.
While human-to-human transmission is rare and generally requires close and prolonged contact with bodily fluids or respiratory secretions, outbreaks have historically affected healthcare workers and others in close contact with patients. Past outbreaks have occurred in Malaysia, India, Bangladesh, Singapore, and the Philippines, with the most notable early outbreak among Malaysian pig farmers in 1998.
The virus has a long incubation period, typically three to 14 days, but can extend up to 45 days. Despite its high mortality, its limited transmissibility means each infected person usually spreads the virus to fewer than one other individual. The WHO categorizes Nipah as a high-risk pathogen due to its severe outcomes and potential for localized outbreaks.
