What's the concern about the new COVID-19 variants? Are they more contagious?
Answer From Daniel C. DeSimone, M.D.
Viruses constantly change through mutation. When a virus has one or more new mutations it’s called a variant of the original virus. Currently, the Centers for Disease Control and Prevention (CDC) has identified one variant of the virus (SARS-CoV-2) that causes coronavirus disease 2019 (COVID-19) as a variant of concern:
- Omicron. This variant spreads more easily than the original virus that causes COVID-19 and the delta variant. However, omicron appears to cause less severe disease. People who are fully vaccinated can get breakthrough infections and spread the virus to others. But the COVID-19 vaccines are effective at preventing severe illness. This variant also reduces the effectiveness of some monoclonal antibody treatments. Omicron has a few major offshoots (sublineages), including BA.5 and BA.2.12.1. BA.5 made up about 88% of COVID-19 infections that had genetic sequencing in the U.S. in August, 2022, according to the CDC.
In April, the CDC downgraded the delta variant from a variant of concern to a variant being monitored. This means that the delta variant isn’t currently considered a major public health threat in the U.S.
To strengthen protection against COVID-19 and circulating variants, the CDC recommends staying up to date with your COVID-19 vaccines and any additional primary shots and boosters for which you are eligible.
Daniel C. DeSimone, M.D.
Aug. 27, 2022
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