Delta, Mu, and Others: What to Know About Covid Variants
Daily Trends in COVID-19 Cases in the U.S. Reported to CDC (9-21-21): red line shows 7-day moving average. Click image to enlarge.
According to the CDC, the delta variant now makes up more than 99% of COVID-19 cases across the U.S. Recently, though, the media has been drawing attention to the mu variant. Should we worry?
How serious are variants?
Viruses constantly change. Mutations might make a virus easier to spread or more virulent, change its clinical presentation, or alter its response to tests, vaccines, or treatment. Or there may be no observable change in its characteristics at all. Some variants simply fade away; others stick around, but can’t compete with more dominant variants and never really get a “foothold” in a particular population. At this time—and this is a pretty big caveat—the COVID-19 mu variant seems stuck in this last category, at least in the U.S.
What about mu?
Although the mu variant has been identified in more than 39 countries, including the U.S., there have been only about 2,000 cases here, mostly in California, Florida, Texas, and New York. The World Health Organization (WHO) calls mu a “variant of […]