People who've had other coronaviruses may have a 'head start' against COVID-19
The July 15 study yielded a second, more surprising finding as well: Among 37 healthy people who had never gotten COVID-19, more than half had memory T cells that could recognize the new coronavirus.
"This might potentially explain why some people seem to fend off the virus and may be less susceptible to becoming severely ill with COVID-19," Dr. Francis Collins, director of the National Institutes of Health, wrote in a blog post about the findings.
The researchers also examined 23 people who had survived SARS, which is a coronavirus, too. The results showed that those survivors still had SARS-specific memory T cells 17 years after getting sick, and also that those same T cells could recognize the new coronavirus.
The Nature study in German patients found similar results: In a cohort of 68 healthy people who'd never had COVID-19, more than one-third had T cells that reacted to the virus.
The findings suggest that our immune system could lean on its past experiences fighting other coronaviruses to better battle the new one.
White blood cells from 20% to 50% of unexposed people significantly react to the new coronavirus, Sette and Crotty wrote in a follow-up analysis published last month, adding, "pre-existing immune reactivity exists to some degree in the general population."
I have also read that some experts say handling livestock, and poultry manure is a best health practice also "It's good for you!!"...turns out grandpa, and dad were right again. ;-)