#Nipah virus infection - #India (#WHO D.O.N., Jan. 30 '26)

 

Situation at a glance

On 26 January 2026, the National IHR Focal Point for India notified WHO of two laboratory‑confirmed cases of Nipah virus (NiV) infection in West Bengal State. 

Both are healthcare workers at the same private hospital in Barasat (North 24 Parganas district). 

NiV infection was confirmed at the National Institute of Virology in Pune on 13 January. 

One case remains on mechanical ventilation as of 21 January, the other case experienced severe neurological illness but has since improved. 

Authorities have identified and tested over 190 contacts, who all tested negative for NiV with support from a mobile BSL‑3 laboratory deployed by the National Institute of Virology, Pune. 

No further cases have been detected to date. 

This event represents the third NiV infection outbreak reported in West Bengal (previous outbreaks reported in Siliguri in 2001 and Nadia in 2007). 

Enhanced surveillance and infection prevention and control (IPC) measures are in place while investigations into the source of exposure are ongoing. 

NiV infection is a serious but rare zoonotic disease transmitted to humans through infected animals (such as bats), or food contaminated with saliva, urine, and excreta of infected animals. 

It can also be transmitted directly from person to person through close contact with an infected person. 

There are currently no licensed medicines or vaccines for NiV infection, however early supportive care can improve survival. 

WHO assesses the risk posed by Nipah to be moderate at the sub-national level, and low at the national, the regional and global levels.

Description of the situation

On 26 January 2026, the India IHR NFP notified WHO of two confirmed NiV infection cases that occurred in West Bengal State. 

Preliminary laboratory testing suggested NiV infection, and confirmation was received from the National Institute of Virology, Pune on 13 January 2026.

The cases were confirmed through Reverse Transcription Polymerase Chain Reaction (RT-PCR) and Enzyme-Linked Immunosorbent Assay (ELISA) testing.

The first case is a female nurse and the second case is a male nurse. 

Both cases were between 20 – 30 years old, from Barasat, North 24 Parganas district. 

Both cases developed symptoms typical of severe NiV infection in late December 2025 and were admitted to hospital in early January 2026. 

As of 21 January 2026, the second case showed clinical improvement, while the first case remained under critical care.

Following the two confirmed cases, Indian health authorities identified and tested over 190 contact persons, including health and care workers and community contacts. All samples from contact persons tested negative for NiV.

The Indian National Centre for Disease Control, announced on 27 January that no further confirmed cases have been detected in West Bengal from December 2025 to date.

Epidemiology

NiV infection is a zoonotic disease transmitted to humans through infected animals (such as bats), or food contaminated with saliva, urine, and excreta of infected animals. It can also be transmitted directly from person to person through close contact with an infected person. Fruit bats or flying foxes (Pteropus species) are the natural hosts for the virus.

The incubation period ranges from 3 to 14 days. In some rare cases incubation of up to 45 days has been reported. Laboratory diagnosis of a patient with a clinical history of NiV infection can be made during the acute and convalescent phases of the disease by using a combination of tests. The main tests used are RT-PCR from bodily fluids and antibody detection via ELISA.

Human infections range from asymptomatic infection to acute respiratory infection (mild, severe), and fatal encephalitis (brain swelling).

Infected people initially develop symptoms including fever, headaches, myalgia (muscle pain), vomiting and sore throat. This can be followed by dizziness, drowsiness, altered consciousness, and neurological signs that indicate acute encephalitis. Some people can also experience atypical pneumonia and severe respiratory problems, including acute respiratory distress. Encephalitis and seizures occur in severe cases, progressing to coma within 24 to 48 hours.

Further information about NiV infection can be found here.

The case fatality ratio (CFR) in outbreaks across Bangladesh, India, Malaysia, and Singapore range from 40% to 75%, depending on local capabilities for early detection and clinical management. There are currently no licensed medicines or vaccines specific for NiV infection. Intensive supportive care is recommended to treat severe respiratory and neurologic complications. Henipavirus nipahense (Nipah virus) is considered a priority pathogen for the acceleration of medical countermeasures (MCMs) to respond to epidemics and pandemics as part of the WHO R&D Blueprint for Epidemics. 

Public health response

Several public health measures have been implemented by local authorities, including:

-- The Government of India, in close coordination with the Government of West Bengal, initiated prompt and comprehensive public health measures in accordance with established protocols.

-- Investigations were conducted in collaboration with other sectors through a One Health coordinated approach.

-- Contact tracing has been carried out around the identified cases, with continuous follow-up.

-- Surveillance efforts have been strengthened and enhanced to ensure early case detection.

-- Health education and awareness campaigns, including community engagement and advocacy, are ongoing.

-- Clinicians have been sensitized and alerted to NiV. Infection prevention and control has been strengthened at health-care settings.

- Prompt sample collection, transportation, and testing were conducted at the reference laboratory teams.

The support provided by WHO includes:

-- Providing event communication support at national and international levels, including the submission of an official IHR notification.

-- Monitoring of the evolving outbreak situation, especially during the ongoing Nipah season, including support for assessment of epidemiological patterns, risk factors, and geographic spread.

WHO risk assessment

Nipah virus (Henipavirus nipahense) is a rare zoonotic pathogen with a high CFR (40-75%) and no licensed vaccine or treatment. 

Its reservoirs are fruit bats or flying foxes (bats in the Pteropus genus), which are distributed in the coastal regions and on several islands in the Indian ocean, India, south-east Asia and Oceania. 

The virus can be transmitted to humans from wild and domestic animals, however, as the disease can be transmitted by domesticated animals, secondary human-to-human transmissions are also possible. 

Cases of Nipah virus infection were first reported in 1998 and since then have been reported in Bangladesh, India, Malaysia, Philippines and Singapore. 

The virus is present in India, with seasonal outbreaks linked to bat activities and cultural practices such as the consumption of raw date palm sap. Seasonal outbreaks occur between December and May, coinciding with the harvesting of date palm sap.

This event represents the 13th Nipah outbreak documented in India and the third reported in West Bengal. 

Since 2001, India has reported 12 Nipah outbreaks prior to this event: 10 in the state of Kerala and two in the state of West Bengal. 

In West Bengal, previous outbreaks occurred in 2001 (Siliguri) and 2007 (Nadia district). 

Based on the current available information, WHO assesses the overall public health risk posed by NiV at the sub-national level to be moderate, taking into consideration no availability of specific drugs or vaccines for NiV infection and the difficulty of early diagnosis. 

Although sensitive and specific laboratory methods exist, the symptoms during the first phase are not specific and could potentially delay a timely diagnosis, outbreak detection and response. 

In addition, fruit bats (Pteropus spp.) are the natural reservoir of NiV, and they are present in India and repeated spillover of the virus from its reservoir to the human population has been demonstrated.

Human-to-human transmission has been documented in previous outbreaks, mostly reported in health-care settings and among family and caregivers of sick people through close contact with bodily fluids. 

Implementation of adequate infection prevention and control measures in health care facilities is critical to mitigate health care associated infection.

The yearly number of NiV infection cases reported in India has remained relatively low since 2001, except for 2001, when 66 cases were reported and 2018 when 18 cases were reported. 

Over the past 5 years, a dozen confirmed cases were reported in India, all in Kerala State. 

Strong public health measures are implemented in India to detect and control outbreaks, including established NiV surveillance, and the availability of Rapid Response Teams (RRT) at both the Central and State levels, along with the capacity to rapidly test samples.

For neighbouring countries, WHO assesses the public health risk posed by NiV at the regional level to be low. There have been no reports of cross‑border transmission, and the current outbreak remains geographically limited. 

Nevertheless, the risk of disease occurrence persists due to the shared ecological corridor of fruit bats and the history of human cases previously reported in the region. India has demonstrated strong capacity and experience in managing past NiV outbreaks.

WHO assesses the public health risk posed by NiV at the global level to be low, as there has been no confirmed spread of cases outside India.

WHO advice

In the absence of a licensed vaccine or specific therapeutic treatment for Nipah virus disease, reducing or preventing infection in people relies on raising awareness of the risk factors. 

This includes providing guidance on and reinforcing risk communication messages about the measures that people can take to reduce exposure to the Nipah virus. This is also important in the context of mass gatherings, where attendees come from different countries and may be unfamiliar with disease and its mode of transmission, as well as actions they can take to protect themselves. and case management should focus on delivering timely supportive care, supported by an effective laboratory system and adequate infection prevention and control measures in health facilities. Intensive supportive care is recommended for treatment of severe respiratory and neurologic complications. 

Public health educational messages should focus on:

-- Reducing the risk of bat-to-human transmission

- Efforts to prevent transmission should first focus on decreasing bat access to date palm sap and other fresh food products. Freshly collected date palm juice should be boiled, and fruits should be thoroughly washed and peeled before consumption. Fruits with signs of bat bites should be discarded. Areas where bats are known to roost should be avoided.

-- Reducing the risk of human-to-human transmission.

- Close unprotected physical contact with NiV-infected people should be avoided. Regular hand washing should be carried out after caring for or visiting sick people along other preventive measures.

-- People experiencing Nipah-like symptoms should be referred to a health facility, as early supportive care is key in the absence of treatment. Contact tracing and monitoring are also key to mitigate human-to-human transmission.

-- Controlling infection in health care settings

- Health and care workers caring for patients with suspected or confirmed infection, or handling specimens from them, should always implement standard precautions for infection prevention and control at all times, for all patients.

- When caring for patients with suspected or confirmed NiV, WHO advises the use of contact and droplet precautions including a well-fitting medical mask, eye protection, a fluid-resistant gown, and examination gloves. Airborne precautions should be implemented during aerosol-generating procedures, including placing the patient in an airborne-infection isolation room and the use of a fit-tested filtering facepiece respirator instead of a medical mask. Suspected or confirmed cases of NiV should be placed in a single-patient room.   For family members and caregivers visiting patients with suspected or confirmed Nipah virus, similar precautions should be applied.   

- Samples taken from people and animals with suspected NiV infection should be handled by trained staff working in suitably equipped laboratories.

Based on the currently available information, WHO does not recommend any travel and/or trade restrictions.

Further information

-- World Health Organization. Nipah virus [Fact sheet]. Geneva: WHO; 2026. Available from: https://www.who.int/news-room/fact-sheets/detail/nipah-virus

-- Ministry of Health and Family Welfare. Only Two Nipah Virus Disease Cases Reported in West Bengal Since Last December: NCDC. 196 Contacts Linked to Nipah Cases Traced and Found Asymptomatic; All Test Negative. https://www.pib.gov.in/PressReleasePage.aspx?PRID=2219219&reg=3&lang=1

-- News On AIR. West Bengal reports two suspected Nipah cases; Centre sends response team. New Delhi: Prasar Bharati; 13 January 2026. Available from: https://www.newsonair.gov.in/west-bengal-reports-two-suspected-nipah-cases-centre-sends-response-team/

-- News On AIR. Centre deploys National Joint Outbreak Response Team in West Bengal after suspected Nipah cases. New Delhi: Prasar Bharati; 12 January 2026. Available from: https://www.newsonair.gov.in/centre-deploys-national-joint-outbreak-response-team-in-west-bengal-after-suspected-nipah-cases/

-- Ministry of Health and Family Welfare (MoHFW). X (formerly Twitter). 11 Jan 2026. Available from: https://x.com/MoHFW_INDIA/status/2010751351232594216

-- World Health Organization, Regional Office for South-East Asia, Epidemiological Bulletin WHO Health Emergencies Programme, 2nd edition (2026), 28 January 2026 Reporting period: 12 to 25 Jan 2026: https://cdn.who.int/media/docs/default-source/searo/whe/wherepib/2026_02_searo_epi_bulletin.pdf

-- World Health Organization (6 August 2025). Disease Outbreak News; Nipah virus infection – India. Available at: https://www.who.int/emergencies/disease-outbreak-news/item/2025-DON577

-- https://www.who.int/news-room/fact-sheets/detail/nipah-virus

-- World Health Organization, Regional Office for South-East Asia. Regional strategy for the prevention and control of Nipah virus infection: 2023–2030. New Delhi: WHO SEARO; 2023. Available from: https://www.who.int/publications/i/item/9789290210849

-- World Health Organization. Technical brief: Enhancing readiness for a Nipah virus event in countries not reporting a Nipah virus event: interim document. Geneva: WHO; 2024 Feb. Available from: https://www.who.int/publications/i/item/9789290211273

-- Kumar SS, Maan S, Kumari M, Gupta P, Bhatia S, Maan NS. Nipah virus disease: epidemiological, clinical, diagnostic and legislative aspects of this unpredictable emerging zoonosis. Animals (Basel). 2023;13(1):159. doi:10.3390/ani13010159. Available from: https://www.mdpi.com/2076-2615/13/1/159

-- Thomas B, Chandran P, Lilabi MP, George B, Sivakumar CP, Jayadev VK, et al. Nipah virus infection in Kozhikode, Kerala, South India, in 2018: epidemiology of an outbreak of an emerging disease. Indian J Community Med. 2019;44(4):383–7. https://pubmed.ncbi.nlm.nih.gov/31802805

-- World Health Organization. Standard precautions for the prevention and control of infections: aide memoire. Geneva: WHO; 2022. Available from: https://www.who.int/publications/i/item/WHO-UHL-IHS-IPC-2022.1

-- Transmission-based precautions for the prevention and control of infections: aide memoire. Geneva: WHO; 2022. Available from: https://www.who.int/publications/i/item/WHO-UHL-IHS-IPC-2022.2

Source: 

Link: https://www.who.int/emergencies/disease-outbreak-news/item/2026-DON593

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#HK, DH follows up on #Nipah virus #infection cluster in #India (Jan. 26 '26)

 

DH follows up on Nipah virus infection cluster in India

In light of reports indicating a cluster of a Nipah virus infection in a certain region of India, the Centre for Health Protection (CHP) of the Department of Health (DH) said today (January 26) that it has proactively sought further information from the World Health Organization (WHO) and Indian health authorities. 

The CHP is also conducting health screenings on inbound travellers from the affected area who exhibit suspected symptoms, with an aim of promptly referring suspected cases to hospitals for investigation. 

Currently, there are no imported or local cases of Nipah virus infection in Hong Kong.

Preliminary information indicated that a hospital in Kolkata, West Bengal, India, has recorded five confirmed cases of Nipah virus infection since mid-January of this year. 

The cluster was mainly due to nosocomial transmission and primarily involved healthcare workers, with no reported deaths or cross-border transmissions to date. 

Approximately 100 close contacts have been quarantined and tested in India. 

The CHP's current risk assessment indicates a low risk of importation of Nipah virus into Hong Kong.

Nipah virus was first identified during outbreaks in Malaysia and Singapore from 1998 to 1999, affecting pig farm workers and individuals with close contact with pigs. 

It can affect various animals, including pigs, horses, goats, sheep, cats and dogs. 

Over the past two decades, multiple outbreaks of human Nipah virus infections were recorded in Bangladesh and India, typically occurring between December and April. 

Transmission primarily occurs through the consumption of raw date palm sap contaminated by fruit bats. India's most recent outbreak occurred in Kerala in mid-2025, involving four cases.

"Nipah virus infection is an emerging zoonotic disease. Fruit bats are the natural host for the virus. The virus is mainly transmitted through direct contact with sick animals via their contaminated respiratory droplets, nasal secretions and tissues. It can also be transmitted via consuming food contaminated with urine, droppings or saliva from infected bats, usually fruits or fruit products (particularly raw date palm sap). Human-to-human transmission is also possible through close contact with contaminated secretions and excretions of infected persons. Such transmission has been reported in patients' household and healthcare settings," the Controller of the CHP, Dr Edwin Tsui, said.

Patients infected with Nipah virus can be asymptomatic. 

Early symptoms include flu-like symptoms, such as fever, headache, vomiting, sore throat and muscle aches. Other symptoms include dizziness, drowsiness and a decrease in consciousness. Severe cases may develop complications such as pneumonia, seizure, encephalitis, coma or even death. The case fatality rate ranges from approximately 40 per cent to 75 per cent. Among the patients who survive acute encephalitis, around 20 per cent of them may have persistent nerve problems. Currently, there is no specific treatment or medication for Nipah virus infection. The mainstay of treatment is limited to supportive care. Symptoms usually start to develop around four to 14 days after exposure, but onset may occur as late as 45 days.

"Hong Kong has the ability to detect infections of unknown causes and emerging infectious diseases at boundary control points and in hospitals. On the immigration level, the DH conducts medical assessments for sick travellers at all boundary control points and refers them to hospitals for medical examinations as needed. The CHP has a robust communicable disease surveillance and notification mechanism that enables medical professionals to report suspected cases. So far, no cases of Nipah virus infection have been recorded. Although there are no direct flights between Kolkata and Hong Kong, the CHP will step up health screenings for passengers arriving from India at the airport as a precautionary measure. Port Health staff have been arranged to carry out temperature screenings for travellers at relevant flight gates, perform medical assessments on symptomatic travellers and refer suspected cases with potential public health implications to hospitals for examination," said Dr Tsui.

Dr Tsui reminded the public to take the following measures to reduce infection risk if travel to Nipah virus-affected areas is unavoidable:

-- Avoid contact with wild animals or sick farm animals, especially bats, farmed pigs, horses, domestic and feral cats.

-- Avoid areas where bats are known to roost.

-- Observe good personal hygiene; wash hands frequently with liquid soap and water, especially after contact with animals or their droppings/secretions, and after taking caring of or visiting sick people.

-- Observe food hygiene by thoroughly washing and peeling fruits before consumption. Fruits with signs of bat bites or found on the ground should not be consumed. Avoid drinking raw date palm sap, toddy or other juice.

 The CHP will monitor the situation and implement appropriate prevention and control measures based on risk assessments to safeguard public health and the well-being of citizens.

 

Ends/Monday, January 26, 2026

Issued at HKT 19:45

Source: 

Link: https://www.info.gov.hk/gia/general/202601/26/P2026012600674.htm?fontSize=1

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