CDC and India Monitor Nipah Outbreak as Asia Tightens Travel Checks

India's Health Ministry said on Jan. 27, 2025 that it had contained a Nipah virus outbreak after confirming two cases detected since December in West Bengal and that 196 identified contacts had tested negative, officials said.

The World Health Organization estimates Nipah fatality rates between 40% and 75%, and health experts warned that international travel could increase spread risk after more than 2,000,000 people traveled from India to the U.S. in 2023, WHO figures and officials show.

A spokesperson for the U.S. Centers for Disease Control and Prevention said the agency is "monitoring the situation and stands ready to assist as needed," while Singapore and Hong Kong instituted temperature checks and mandatory health declarations and the U.K. issued a travel advisory, officials confirmed.

India has confirmed two Nipah cases, both involving nurses, and authorities expanded monitoring to 196 people — an increase of 86 from the previous day — centered at a hospital about 15 miles outside Kolkata, officials said.

No Nipah cases have been detected in the U.S., and officials said symptoms typically appear four to 21 days after exposure, there is no approved treatment and multiple vaccines are being tested, so enhanced surveillance and testing will continue.