Comments by "Darlene" (@darlene2709) on "CBC News"
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It's not actually a law. "As evidence mounts that the omicron variant is less deadly than prior COVID-19 strains, one oft-cited explanation is that viruses always evolve to become less virulent over time.
The problem, experts say, is that this theory has been soundly debunked. The idea that infections tend to become less lethal over time was first proposed by notable bacteriologist Dr. Theobald Smith in the late 1800s. His theory about pathogen evolution was later dubbed the "law of declining virulence."
But over the past 100 years, virologists have learned that virus evolution is more chaotic. Virus evolution is a game of chance, and less about grand design. In some cases, viruses evolve to become more virulent.
Continued virus survival, spread and virulence are all about the evolutionary pressures of multiple factors, including the number of people available to infect, how long humans live after infection, the immune system response and time between infection and symptom onset.
Unfortunately, that means it's nearly impossible to predict the future of the pandemic, because viruses don't always evolve in a predictable pattern." Reuters
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