Genetic Engineering & Biotechnology News
Zoonotic viruses fill us with dread—and rightly so. Such viruses have been known to spread from animals to human hosts, transmitting deadly diseases such as Ebola, rabies, and bird flu. And according to virologists and other scientists with relevant expertise, the SARS-CoV-2 virus, the source of the COVID-19 pandemic, is believed to have originated in bats, though pangolins are suspected intermediaries.
Little wonder, then, that when we think of species-jumping vertebrate-infecting viruses, we usually imagine them jumping toward us. But according to a new study from University College London (UCL) researchers, these viruses are more likely to jump in the other direction—away from us and toward other vertebrate species.
The study appeared in Nature Ecology & Evolution, in an article titled, “The evolutionary drivers and correlates of viral host jumps.”
“[We] harnessed the entirety of publicly available viral genomic data, employing a comprehensive suite of network and phylogenetic analyses to investigate the evolutionary mechanisms underpinning recent viral host jumps,” the article’s authors wrote. “Surprisingly, we find that humans are as much a source as a sink for viral spillover events, insofar as we infer more viral host jumps from humans to other animals than from animals to humans.”
The UCL researchers analyzed the nearly 12 million viral genomes that have been deposited on public databases to date. Leveraging this data, they reconstructed the evolutionary histories and past host jumps of viruses across 32 viral families, and they looked for which parts of the viral genomes acquired mutations during host jumps.