ATLANTA — Social media posts are once again circulating online claiming viruses always weaken as they mutate, suggesting we should expect the same from COVID-19.
But is that's true?
THE QUESTION
Do viruses always weaken as they mutate?
THE SOURCES
- The World Health Organization
- Dr. Ted Ross, Director of the Center for Vaccines and Immunology and Georgia Research Alliance Eminent Scholar and Professor of Infectious Diseases at the University of Georgia
- Dr. Cherie Drenzek, Georgia's state epidemiologist
THE ANSWER
No, viruses do not always weaken with mutations. Sometimes mutations can lead to a strain that's more transmissible or capable of causing more disease.
WHAT WE FOUND
"When a virus enters a human cell they replicate," Dr. Drenzek explained. "And when they do that, they have a tendency over time to make mistakes."
Those mistakes, or mutations, refer to a change in a virus's genetic code. Drenzek said mutations happen frequently and can change the virus in a number of ways.
Most mutations are tiny and insignificant, according to the World Health Organization, and some new combinations don't work causing the virus to weaken and strains to die out.
"In general, viruses tend not to want to kill their host before they transmit to the next person," Ross said. "So there are adaptations that occur to make it more humanized."
But Ross emphasized that does not guarantee the way a virus evolves can be predicted.
At times, mutations can make the virus better at spreading or causing disease.
"The general blanket statement that they always adapt and mutate and therefore if they mutate, they become less pathogenic, is not correct," Ross said.
According to our sources, the claim that viruses always weaken as they mutate is false. Experts like Drenezk said the trajectory is dependent on multiple factors, namely whether genetic changes in the virus end up being big or small.
Drenzek also emphasized that factors like a population's vaccine use can also impact how a virus evolves.
"Even if we cannot predict what variant is next," Drenzek said, "I can predict, our immune systems are really smart and vaccination makes them smarter than ever."