SARS viruses infect 400,000 annually, says study

Just how exactly the Covid-19 virus was transmitted from bats to humans for the first time is still unclear. But what seems clear now is that infectious particles from bats can easily transfer to humans – and they have done so for many years. Now a new study estimates that 400,000 people on average are likely infected with SARS-related coronaviruses every year, in spillovers that never grow into detectable outbreaks. Let’s see how the researchers arrived at this conclusion