225 people died in 20 years across the country
A group of researchers has warned that the Nipah virus (NiV) could cause another epidemic in Bangladesh, India, and other countries of Asia.
"The virus is more contagious than previously thought," said a study published in The Proceedings of the National Academy of Sciences (PANS) in the United States.
There is fear now that the Nipah virus could become more transmissible to settlements in any region, it said.
The results of a six-year study conducted by the EcoHealth Alliance, a nonprofit organization working at the intersection of animal, environmental, and human health on a global scale, were released on November 3.
The research report was edited by Dr Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases in the United States and a renowned infectious disease specialist.
Nipah virus was first identified in 1999 after an outbreak in pigs that went on to infect nearly 300 people who were in contact with the pigs.
The researchers revealed that the Nipah virus is not as confined to what is traditionally known as the Nipah belt along the Bangladesh-India border as previously thought.
Human outbreaks occur almost annually in Bangladesh from November to April, according to the researchers.
In annual outbreaks throughout Bangladesh, Nipah virus kills around 70% of the people it infects. Those who survive the acute encephalitis make a full recovery, but around 20% are left with residual neurological consequences such as persistent convulsions and personality changes.
Nipah is a distant relative of measles but has no vaccine and no effective medical countermeasures. It can cause brain swelling and commas. Outbreaks are often linked to consumption of raw date palm sap and through contact with intermediate hosts such as domesticated animals or bats.
“Nipah circulates regularly in large fruit-eating bats throughout many parts of Asia, but human outbreaks can only occur when there is a route of transmission from bats to humans,” Dr. Jonathan Epstein, lead author and EcoHealth Alliance Vice President for Science and Outreach.
The virus can cause fever, headache, muscle aches, nausea, and even lung infections.
‘225 deaths in 20 years’
Bangladesh has reported 225 deaths out of 319 positive cases in 20 years (2001-2020), according to The Institute of Epidemiology, Disease Control and Research (IEDCR).
Among the six Nipah virus infections, four deaths were reported in 2020.
According to the World Health Organization (WHO), in Bangladeshi and Indian outbreaks, consumption of fruits or fruit products (e.g. raw date palm juice) contaminated with urine or saliva from infected fruit bats was the most likely source of infection. Fruit bats of the family Pteropodidae – particularly species belonging to the Pteropus genus – are the natural hosts for the Nipah virus. There is no apparent disease in fruit bats.
For long, scientists have had the idea that the disease occurs in areas where juice is collected from date palms. But now infection has been found in places where there are no date palms. Even people who did not drink the juice have been infected, said Jonathan Epstein.
"The virus is repeatedly knocking on the door," he says.
“It’s repeatedly going from bats to humans. But we are afraid that it may contain genetic strains or variants that can be easily spread from person to person. It could lead to a major epidemic,” he warned.
Although the outbreak is still sporadic, the researchers called on the world to be vigilant.