German researchers believe having prior “common cold” coronaviruses may prepare some to handle Covid-19 better

https://medicalxpress.com/news/2020-07-prior-exposure-common-cold-viruses.html

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Universitätsmedizin Berlin and the Max Planck Institute for Molecular Genetics (MPIMG) show that some healthy individuals possess immune cells capable of recognizing the novel coronavirus, SARS-CoV-2. The reason for this might be found in prior infections with 'common cold' coronaviruses. Whether or not this cross-reactivity has a protective effect on the clinical course in individuals infected with SARS-CoV-2 will now be addressed by the 'Charité Corona Cross' study.
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In Germany, coronaviruses are responsible for up to 30 percent of all seasonal colds, says Prof. Dr. Andreas Thiel

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