Five cases of Nipah virus have been confirmed in the eastern Indian state of West Bengal, including infected doctors and nurses, and India is moving quickly to contain the Nipah virus outbreak.
According to local media reports, nearly 100 people have been asked to quarantine at home, and infected patients are being treated in hospitals in and around the capital Kolkata, with one patient in critical condition.
Nipah virus is a deadly virus with no vaccine or cure and is considered a high-risk pathogen by the World Health Organization. Experts say human infections are rare and usually occur when the virus is spread from bats, often through contaminated fruit.
Here’s everything you need to know about the virus:
Nipah virus (NiV) infection: what are the symptoms?
Nipah virus (NiV) infection often begins with nonspecific symptoms, making early detection difficult.
The incubation period is generally considered to be four to 21 days, according to the Centers for Disease Control and Prevention (CDC), although during previous outbreaks, there have been reports of longer delays between exposure to the virus and illness in rare cases.
Patients often develop a sudden, flu-like illness characterized by fever, headache, muscle aches, and fatigue. In some cases, respiratory symptoms such as cough, shortness of breath, or pneumonia may also occur, although the timing and severity of these symptoms can vary widely.
The most serious and well-established complication of Nipah infection is inflammation of the brain, called encephalitis. Neurologic symptoms, including confusion, altered consciousness, seizures, or coma, usually appear days to weeks after the initial episode.
Some patients may also develop meningitis.
document. An officer directs traffic while another officer directs traffic in fog in the Shillong area of southern Johor state on May 10, 1999. – Malaysia expanded its pig cull to Johor and the eastern state of Kelantan after test results showed 40 pigs tested positive for the deadly Nipah virus (AFP via Getty Images)
How deadly is Nipah virus?
Nipah virus is associated with high mortality rates, with reported mortality rates ranging from 40% to 75%, depending on the outbreak and the strain involved.
Survivors may experience long-term neurological effects, such as persistent seizures or personality changes, according to the latest update from the UK Health Safety Authority.
In rare cases, encephalitis has been reported to recur months or even years after the initial infection, possibly due to relapse or reactivation of the virus.
How is Nipah virus spread?
According to the World Health Organization, Nipah virus is a zoonotic pathogen that can be transmitted from animals to humans and between humans.
The main natural carriers are fruit bats (Pterosaur species); humans may become infected through direct contact with infected bats or other animals, or by eating food contaminated with bat saliva, urine, or feces.
Human-to-human transmission has also been reported, particularly through close contact with the body fluids of an infected person.
document. Health workers wearing protective gear move a man showing symptoms of Nipah virus to an isolation ward at a government hospital in Kozhikode, in the southern Indian state of Kerala, on September 16, 2023 (AFP via Getty Images)
Where was Nipah virus first discovered?
Nipah virus (NiV) was first discovered in 1999 following an outbreak of encephalitis and respiratory disease among pig farmers and others in close contact with infected pigs in Malaysia and Singapore. This incident led to the recognition that NiV is a serious zoonotic pathogen capable of being transmitted from animals to humans.
Since then, there have been multiple outbreaks in South Asia. Cases have been reported in parts of northeastern India and several districts in Bangladesh, where outbreaks have occurred almost every year since 2001.
In southern India, the first Nipah outbreak was reported in the state of Kerala in 2018, followed by sporadic cases in subsequent years.
In addition to South Asia, infections have also been reported in the Philippines, and investigations suggest they are caused by Nipah virus or a closely related Nipah virus strain.
document. A health worker wearing protective gear handles biohazard waste from a Nipah Virus Isolation Center at a government hospital in Kozhikode, in the southern Indian state of Kerala, on September 16, 2023 (AFP via Getty Images)
Scientific research has identified fruit bats as the natural host of the virus. Nipah virus was isolated from bat urine in Malaysia, and antibodies have been detected in at least 23 species of bats in Asia and parts of Africa, including Ghana and Madagascar.
Despite the wide animal host range, confirmed human outbreaks so far have been limited to South and Southeast Asia, often in rural or semi-rural areas where contact between humans, bats and livestock is more likely, WHO said.
“Human-to-human transmission of Nipah virus has also been reported among family members and caregivers of infected patients,” the World Health Organization said.
Is there any treatment?
There are currently no proven targeted treatments for Nipah virus (NiV) infection, and there are no approved vaccines to prevent the virus.
Patient care remains primarily supportive, with a focus on management of symptoms and complications as they arise.
The World Health Organization classifies the virus as a priority pathogen in its research and development blueprint, which identifies pandemic threats that require urgent research.
Reduce the risk of Nipah infection:
Global health agencies advise that with no vaccine available, preventing Nipah virus infection relies on awareness and simple protective measures. Public health advice focuses on reducing contact with the virus, whether from bats, animals or infected people.
To prevent bat-to-human transmission: Bats are the primary transmitters of Nipah virus. World Health Organization guidelines recommend that people avoid consuming raw date juice or fruit that may be contaminated by bats.
Boiling fresh date juice and washing or peeling the fruit thoroughly can reduce the risk. Health agencies advise that any fruit showing signs of bat bites should be discarded.
To prevent animal-to-human transmission: Personnel handling sick animals, their tissues, or during slaughter should wear gloves and protective clothing. Contact with infected pigs should be minimized and pig farms in fruit bat areas should take steps to protect feed and pens from bats.
To prevent human-to-human transmission: Avoid close, unprotected contact with people infected with Nipah virus. Regular hand washing after caring for or visiting someone who is sick is critical to stopping the spread of the virus.
Nipah virus in popular culture:
2011 movies infectAccording to the website of global health nonprofit Path, it depicts a virus that is spreading rapidly around the world and is partly inspired by real-life pathogens such as Nipah virus, a bat-borne virus first discovered in Malaysia in 1999.
Nipah virus causes severe respiratory illness and brain inflammation (encephalitis) and can be transmitted from animals to humans, contaminated food, or infected people.
Its high death rate, potential for outbreaks, and lack of a vaccine made it a model for how zoonotic viruses can trigger pandemics, and filmmakers used it to shape real-life global crises infect, The path is noted.