Several Asian countries strengthened health screening and surveillance measures for travelers arriving from West Bengal, India, after two laboratory-confirmed Nipah virus infections were reported in January 2026.
Thailand introduced enhanced screening at international airports for passengers arriving from West Bengal, while authorities in the region increased surveillance and preparedness measures because of the virus’s potential for person-to-person transmission.
The West Bengal event involved two healthcare workers from the same private hospital in Barasat, North 24 Parganas. Indian authorities identified and tested 196 contacts linked to the cases, with all contacts testing negative at the time of the January public-health assessment.
One of the two healthcare workers later died on February 12, 2026, according to a WHO South-East Asia technical update.
What Is Nipah Virus?
Nipah virus (NiV) is a zoonotic virus that can spread from infected animals to humans and can also be transmitted between people through close contact.
Fruit bats are the natural reservoir of Nipah virus. Human infection can occur through contact with infected animals, food contaminated by infected animals, or close contact with an infected person. WHO also identifies contaminated fruit and fruit products, including raw date palm juice, as potential sources of infection.
Nipah infection can range from mild or asymptomatic illness to severe respiratory disease and encephalitis, an inflammation of the brain. Severe neurological complications can include seizures, coma and death.
There are currently no licensed vaccines or specific medicines for Nipah virus infection. Treatment relies on supportive medical care, particularly for patients who develop serious respiratory or neurological complications.
What Happened in West Bengal?
India notified WHO in January 2026 about two laboratory-confirmed Nipah virus infections in West Bengal.
Both patients were healthcare workers at the same private hospital in Barasat in North 24 Parganas district. The infections were confirmed by the National Institute of Virology in Pune.
Indian health authorities immediately began contact tracing, testing, enhanced surveillance and infection-prevention measures.
A total of 196 contacts were identified, traced, monitored and tested. India’s Ministry of Health and Family Welfare reported on January 27 that all identified contacts were asymptomatic and had tested negative for Nipah virus, with no additional confirmed cases detected at that time.
The West Bengal event was the state’s third reported Nipah outbreak, following outbreaks in Siliguri in 2001 and Nadia in 2007.
Why Did Other Asian Countries Increase Screening?
Nipah virus can spread through close contact, particularly among household members, caregivers and healthcare workers. Previous outbreaks have demonstrated the importance of early detection, isolation, contact tracing and infection-prevention measures.
Thailand responded by strengthening health screening at international entry points for passengers arriving from West Bengal.
Thailand’s Department of Disease Control reported that screening measures began at Suvarnabhumi and Don Mueang airports on January 25, 2026. Phuket International Airport also strengthened preparedness and screening procedures for passengers arriving from the affected area.
These measures were intended as precautionary public-health measures to identify possible symptomatic travelers and reduce the risk of international spread.
What Are the Symptoms of Nipah Virus Infection?
Nipah virus infection can initially resemble other viral illnesses.
Possible symptoms include:
- Fever
- Headache
- Muscle pain
- Vomiting
- Sore throat
- Drowsiness
- Respiratory symptoms
- Confusion
- Seizures
- Encephalitis
Severe disease can progress rapidly to neurological complications, including coma. WHO notes that early symptoms are not specific, which can make early diagnosis difficult.
Anyone experiencing concerning symptoms after a potential exposure should seek medical advice and inform healthcare professionals about their recent travel and exposure history.
Is There a Nipah Virus Vaccine?
There is currently no licensed vaccine specifically available to prevent Nipah virus infection.
There are also no licensed specific antiviral medicines for Nipah infection. Medical management focuses on supportive care and treatment of complications. Nipah remains a priority pathogen for research into vaccines, treatments and other medical countermeasures.
How Does Nipah Virus Spread?
Nipah virus can reach humans through several routes.
Animal-to-human transmission
Fruit bats are the natural reservoir of the virus. Infection can occur when people come into contact with infected animals or consume food contaminated by infected animals.
Foodborne transmission
Contaminated fruit or fruit products can transmit the virus. WHO specifically identifies raw date palm juice contaminated by infected bats as one potential route.
Person-to-person transmission
Human-to-human transmission has occurred during previous outbreaks, particularly among household caregivers and healthcare workers who had close contact with infected patients or bodily fluids.
What Should Travelers Know?
Travelers should follow the instructions issued by health authorities in the countries they are visiting or departing from.
Travelers arriving from areas affected by a Nipah virus event may encounter additional health screening, health declarations, temperature or symptom checks, or requests for information about recent travel and exposure.
People who develop symptoms after potential exposure should seek medical attention and clearly explain their travel and exposure history.
Travelers should also avoid unnecessary contact with potentially infected animals and follow official food-safety and public-health advice.
Nipah Virus and Nepal
Nepal shares a long land border with India, making infectious-disease surveillance at border crossings particularly important when significant outbreaks occur in neighbouring Indian states.
For travelers entering Nepal from affected areas, the most important advice is to follow any health screening, surveillance or travel requirements issued by Nepalese authorities.
Travelers should rely on official public-health guidance rather than social-media claims or unverified reports.
Nipah Virus Outbreaks in India
Nipah virus has caused repeated outbreaks in India, particularly in Kerala and West Bengal.
West Bengal previously recorded outbreaks in Siliguri in 2001 and Nadia in 2007. Kerala has experienced recurrent outbreaks, including major events since 2018.
In June 2026, WHO reported a separate laboratory-confirmed Nipah infection in Kozhikode district, Kerala. As of June 18, 104 contacts had been identified and monitored, with no secondary cases reported at that point.
This later Kerala case should be distinguished from the January West Bengal event.
The First Known Nipah Outbreak
The first recognised Nipah virus outbreak occurred in Malaysia in 1998–1999 and was associated with pig farming.
The outbreak resulted in 265 human cases and 105 deaths in Malaysia, while approximately 1.1 million pigs were culled as part of efforts to control the disease. The outbreak also affected Singapore.
Fruit bats were subsequently identified as the natural reservoir of Nipah virus.
How Can Nipah Virus Risk Be Reduced?
Public-health authorities focus on several measures to reduce transmission:
- Early identification of suspected cases.
- Isolation of infected or suspected patients.
- Contact tracing and monitoring.
- Appropriate infection-prevention measures in healthcare settings.
- Avoiding contact with potentially infected animals.
- Avoiding food that may have been contaminated by infected animals.
- Following official health and travel guidance.
- Seeking medical attention after potential exposure and developing compatible symptoms.
What Is the Current Risk?
The risk posed by Nipah virus depends on the specific outbreak, transmission patterns and public-health response.
For the January 2026 West Bengal event, WHO assessed the risk as moderate at the sub-national level and low at regional and global levels at the time of its assessment. No international spread was identified from that event.
The later Kerala event reported in June 2026 was also geographically limited at the time of WHO’s assessment, with no secondary transmission identified as of June 18.
The Bottom Line
Nipah virus is a serious but relatively rare zoonotic infection that can cause severe neurological and respiratory disease.
The 2026 West Bengal event prompted increased surveillance and travel-health measures, including enhanced screening in Thailand. India’s response included contact tracing and testing, while WHO assessed the international risk from the West Bengal event as low at the time of its January assessment.
Travelers should rely on current guidance from health authorities, follow screening requirements and seek medical advice if they develop symptoms after a potential exposure.
This article provides general information and is not a substitute for medical advice. Health and travel requirements can change as outbreak investigations develop.
Frequently Asked Questions About Nipah Virus
What is the Nipah virus?
Nipah virus is a zoonotic virus that can spread from infected animals to humans and between people through close contact. Fruit bats are the natural reservoir, and infection can cause severe respiratory illness and encephalitis.
Is there a Nipah virus outbreak in India?
India reported two laboratory-confirmed Nipah virus infections in West Bengal in January 2026. A separate laboratory-confirmed case was reported in Kerala in June 2026. These were separate events.
How does Nipah virus spread?
Nipah virus can spread through contact with infected animals, contaminated food or fruit products, and close contact with infected people. Human-to-human transmission has particularly been documented among healthcare workers and caregivers.
What are the symptoms of Nipah virus?
Symptoms can include fever, headache, muscle pain, vomiting, sore throat, drowsiness, respiratory symptoms and neurological problems. Severe infection can progress to encephalitis, seizures, coma and death.
Is there a vaccine for Nipah virus?
There is currently no licensed Nipah virus vaccine and no licensed medicine specifically targeting the infection. Treatment focuses on supportive medical care and management of complications.
Did the 2026 West Bengal Nipah cases spread internationally?
WHO did not report international spread from the January 2026 West Bengal event. Thailand nevertheless introduced enhanced screening measures for passengers arriving from West Bengal as a precautionary public-health measure.
How many contacts were tested after the West Bengal cases?
India reported that 196 contacts linked to the two confirmed West Bengal cases were identified, traced, monitored and tested. All were reported as asymptomatic and negative at the time of the January 27 update.
Should travelers be worried about Nipah virus?
Travelers should follow current advice from official health authorities. The risk varies depending on the outbreak and location. WHO assessed the international risk from the January 2026 West Bengal event as low, while recommending continued surveillance and preparedness.
Can Nipah virus spread from person to person?
Yes. Person-to-person transmission has occurred, particularly through close contact with infected people and their bodily fluids. Healthcare workers and caregivers can face increased exposure risk without appropriate infection-prevention measures.
Where was Nipah virus first identified?
The first recognised Nipah virus outbreak occurred in Malaysia in 1998–1999. It caused 265 human cases and 105 deaths in Malaysia, with approximately 1.1 million pigs culled during the response.