An-Najah News - As COVID-19 has hitchhiked around the globe, causing lockdowns, pneumonia and fear, scientists have been racing to determine where the SARS-CoV-2 coronavirus has come from.

A study raises some interesting possibilities regarding the origin of the new coronavirus. One of the scenarios suggests the virus may have been circulating harmlessly in human populations for quite a while before it became the pandemic that's now stopped the world in its tracks.

"It is possible that a progenitor of SARS-CoV-2 jumped into humans, acquiring through adaptation during undetected human-to-human transmission," the team from the US, UK and Australia writes in the study.

"Although no animal coronavirus has been identified that is sufficiently similar to have served as the direct progenitor of SARS-CoV-2, the diversity of coronaviruses in bats and other species is massively undersampled," the researchers write.

The second hypothesis is that the natural selection happened in humans - after the virus was transmitted from an animal host.

"The second scenario is that the new coronavirus crossed from animals into humans before it became capable of causing human disease," director of the National Institute of Health, Francis Collins explains on the NIH blog.

"Then, as a result of gradual evolutionary changes over years or perhaps decades, the virus eventually gained the ability to spread from human-to-human and cause serious, often life-threatening disease."

In the meantime, wash your hands, stay home, and help with the effort if you can.