Nipah virus was first identified in Malaysia in 1998. Cases such as the recent death of a boy in Kerala, India have raised concerns that it could mutate and increase its efficiency of transmission, leading to widespread circulation.
That scenario is frightening as the virus currently has a case fatality rate of over 50% and there is no vaccine or tried-and-tested treatment.
But before we can invest resources into vaccine development against Nipah we need to assess whether it is a realistic pandemic threat. And even if it is, there are other viruses out there, so we must understand where it should rank on the list of priorities…
A long-term study in Bangladesh, where regular Nipah virus outbreaks occur among its people, suggests that bat population density, virus prevalence and people drinking raw date palm sap are the main factors explaining the pattern of transmission. The bats contaminate the sap while it is being tapped from the date palm tree, and it is then consumed locally.
That is an important finding. As we have seen with SARS-CoV-2, better transmitting viruses evolve while the virus is circulating among its human, not animal, hosts. So, keeping the number of infections in people to a minimum not only minimizes the death rate from Nipah itself but also reduces the chance of virus adaptation. Stop the transmission and you stop the pandemic threat.
In the cases of human infection, so far, there has been limited spread to only close contacts of the primary infected individual, such as family members or, if the person is hospitalized, hospital staff… (Select link below to read whole article)