A recent 6-year study by EcoHealth Alliance has found that the Nipah virus is not bound to its ‘belt’ and can happen at any time of the year. So it’s important to pay closer attention to areas where Nipah outbreaks may have not been previously reported.
There’s some terrible, terrible news about Nipah virus. Yes, the same virus that terrorised Kerala and left 17 dead in 2018. It also inspired a movie in 2011 called Contagion and another one in 2019 simply called Virus. Now, to the news.
A non-profit organisation EcoHealth Alliance has released findings of their six-year-long study. Researchers studied how the Nipah outbreaks happened and what could be done to prevent them. The findings are disconcerting, especially at a time when the world is trying to contain the coronavirus. Minks and Coronavirus: These furry mammals are the latest COVID casualty.
What is the Nipah virus?
Nipah is a virus that is transmitted from animals, mostly fruit bats and pigs, to humans. It can cause respiratory illnesses or encephalitis (inflammation of the brain) in infected people.
A couple of reasons make the Nipah virus an international concern. The virus’ vectors — bats — are widely distributed in Asia, interacting closely with humans and livestock. ‘Do NOT wear N95’: CDC just schooled us on how to wear a mask.
The virus can jump directly to humans from bats or domestic animals. It can also spread from person to person.
Spillover of the Nipah virus has occurred in highly populous and internationally-connected places.
Highly dangerous, Nipah virus can kill 75% of those infected. Presently, there is no treatment or vaccine for Nipah virus infection. The only resort is supportive care.
It’s easy to see why the virus is on the WHO R&D Blueprint list, which is a top priority list for vaccine development.
What the study says
Nipah virus cases were thought to be confined to a ‘Nipah belt’ (western Bangladesh) during a certain time of the year (November to April).
The study, which researched eight bat colonies from 2006 to 2012, were able to debunk these beliefs. They found out that Nipah cases were not bound by geography or by time. They could happen throughout the country at any time of the year. Yikes!
Of the eight colonies the researchers studied, Nipah antibodies were present in each location. In one colony, bats suffered outbreaks approximately every two years when bats lose their herd immunity.
The data collected by the researchers indicate that these routine outbreaks in bat populations cause the sporadic nature of Nipah outbreaks in South Asia.
The study notes that the bats carry the Nipah virus across Bangladesh, not just in the belt, and can shed it at any time of the year.
What does this mean?
The findings say that there could be a risk of the virus spilling over to the human population. The global medical community may even be missing cases of smaller outbreaks.
“The problem is, we don’t have a good handle on where else in the world spillover may be happening, which means we’re likely missing outbreaks. Risk is not so much limited by geography as it is by human behavior. This is a virus that spreads from person to person and is lethal in three-quarters of those it infects, which is why we have to pay close attention to it and do what we can to prevent outbreaks,” said Dr Epstein.
The strains of Nipah virus responsible for outbreaks in humans reflect the strains carried by local bats. Different areas of the country had different strains of the virus.
This genetic difference in the NiV may impact the severity of the disease and the chances of it transmitting to humans.
What’s the way forward?
The Nipah virus doesn’t spread as easily as COVID-19 but has a higher fatality rate. So the study suggests looking outside the Nipah belt where cases have not been previously reported. This could ensure that the small outbreaks do not lead to bigger ones.
The findings of the study have been published in the journal Proceedings of the National Academy of Sciences of the United States of America.