The following is an excerpt from Medscape.
About 95% of Americans ages 16 and older have coronavirus antibodies, according to CDC data from testing blood donor samples.
The percentage includes antibodies formed from both vaccinations and Covid-19 infections, with nearly 70% of people ages 16 and up having received at least one vaccine dose, the data shows.
As public health experts have tracked the effects of antibodies on coronavirus reinfection, they've noted a difference between people who have antibodies from vaccines and those who have them from being infected before.
Antibodies from vaccination tend to decline about 4 to 6 months after a shot, CNBC reported.
The data about antibodies from an earlier infection is uncertain, with protection lasting from a few months to more than a year after infection.
Even then, about one-third of people who contract Covid-19 may not develop antibodies at all, according to a CDC study published in September 2021.
The current 7-day average of new Covid-19 cases is hovering around 30,000, according to the latest data from Johns Hopkins University. (Continued)
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