November 7, 2016
This post originally appeared on NPR – Goats and Soda.
One mutation. A simple tweak in the Ebola gene — a C got turned into a T. That’s all it took to make Ebola more infectious during the West Africa epidemic, scientists report Thursday.
Two studies, published in the journal Cell, found that a single mutation arose early in the epidemic. It allows Ebola to infect human cells more easily than the original version of the virus — way more easily.
“The largest difference we saw was about a fourfold increase in the number of cells infected,” says Jeremy Luban, a virologist at the University of Massachusetts Medical School, who led one of the studies. “When you’re talking about a virus that could kill you, this is a pretty scary number.”
When Ebola appeared in West Africa late in 2013, it spread faster and further than any previous Ebola outbreak. One reason was because it hit densely populated cities. And countries in West Africa didn’t have the tools to stop the epidemic.
But early on, computational biologists at Harvard University also noticed the virus was changing. Its genes were mutating.
That’s not surprising, Luban says, on its own. It’s what viruses do, especially when they first start spreading in people.
But the mutations raised a big concern: “Is this virus somehow becoming more transmissible, more dangerous or more deadly?” Luban says.
The computational biologists were stumped. They could see the mutations, but they didn’t know what they did.