Among the thousands of samples of the long strand of RNA that makes up the coronavirus, 11 mutations have become fairly common. But as far as we know, it’s the same virus infecting people all over the world, meaning that only one “strain” of the virus exists, said Peter Thielen, a molecular biologist with the Johns Hopkins Applied Physics Laboratory.
Only one of those common mutations affects the “spike protein,” which enables the virus to infect cells in the throat and lungs. Efforts to produce antibodies that block the spike protein are central to many efforts to develop a vaccine. Since the spike protein has changed little so far, some scientists believe that’s a sign that it can’t alter itself very much and remain infectious.
There’s still a lot about the virus we don’t know. We don’t even know if people are immune to the virus if they’ve caught it already, nor how long that immunity could last, though work is well underway to understand these things.
Mr. Thielen says it is still unclear how those mutations in the genome will ultimately affect countermeasures like a vaccine.
“We just have to keep looking,” he said.