All American Bulletin

Nipah Virus: Key Facts, Symptoms, and How It Spreads

The World Health Organization confirmed on Thursday that two cases of a rare but deadly virus have been identified in an eastern Indian state.

The virus, known as Nipah, is fatal in more than half of the people it infects. First identified in Malaysia and named after the village where the initial case was discovered, Nipah belongs to the same virus family as measles. However, while measles spreads far more easily, Nipah is significantly more lethal.

How the virus spreads

Nipah is a zoonotic virus, meaning it can pass from animals to humans. According to the U.S. Centers for Disease Control and Prevention, transmission most often occurs through direct contact with infected pigs or fruit bats. People can also become infected by consuming fruit or fruit-based products—such as fresh date palm sap—that have been contaminated by bat saliva or urine.

In some cases, the virus spreads from person to person. This type of transmission typically requires close and prolonged contact with someone who is infected.

Early and advanced symptoms

Symptoms usually appear between four and 14 days after exposure, the WHO says. Cases without symptoms are uncommon.

Early signs are often vague and resemble the flu, including fever, headache, muscle aches, vomiting, and sore throat. In roughly two-thirds of patients, the illness worsens quickly, with some falling into a coma within five to seven days. Respiratory issues, such as coughing and abnormal chest X-rays, may also occur.

Many patients show abnormalities in the fluid surrounding the brain, similar to other viral brain infections. Brain scans often reveal tissue damage, and changes in brain electrical activity can indicate how severe the disease may become.

Why health experts are concerned

The CDC classifies Nipah as a biosafety level 4 virus, placing it in the same category as Ebola due to its extreme danger. It is also considered a potential bioterrorism threat.

Despite the limited number of outbreaks, health officials view Nipah as a serious public health risk because of its high death rate, ability to spread between people, potential to cause outbreaks, and the absence of approved vaccines or targeted treatments.

In severe cases, the virus can damage areas of the brain that control essential functions such as eye movement, heart rate, and blood pressure, sometimes resulting in permanent neurological harm.

Survivors frequently report long-term fatigue and ongoing neurological problems that can last for years.

How doctors confirm infection

Doctors typically diagnose Nipah through laboratory testing, often using blood samples to identify and measure specific viral proteins.

Available medical care options

There is currently no approved vaccine or specific antiviral treatment for Nipah. Medical care focuses on managing symptoms and providing supportive treatment. Patients with serious neurological complications may require ventilator support.

An antiviral drug called ribavirin, commonly used alongside other medications to treat chronic hepatitis C, has shown limited potential benefits, though study results have been inconsistent.

As a result, prevention remains the primary strategy, including limiting contact between humans and infected animals and enforcing strict infection-control measures when caring for patients.

Regions where outbreaks are reported

Outbreaks are reported almost every year in parts of South and Southeast Asia, including Bangladesh, India, Malaysia, the Philippines, and Singapore. Bangladesh has recorded the highest number of cases, largely because fruit bats—the natural carriers of the virus—are native to the region.

How rare the virus is globally

Nipah infections are extremely rare. As of 2024, approximately 754 cases have been documented worldwide, though experts believe the true number may be higher due to underreporting.