Common Colds and COVID-19

Common colds train the immune system to recognize COVID-19

By Rachael Rettner - Senior Writer 3 hours ago

This existing immune system "memory" may explain why some people have milder COVID-19 infections.

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Previous infections with common cold viruses can train the immune system to recognize SARS-CoV-2, the virus that causes COVID-19, according to a new study.

The study, published Aug. 4 in the journal Science, found that immune cells known as T cells that recognize common cold coronaviruses also recognize specific sites on SARS-CoV-2 — including parts of the infamous "spike" protein it uses to bind to and invade human cells.

This existing immune system "memory" may explain why some people have milder COVID-19 infections compared with others; however, the authors stress that this hypothesis is "highly speculative" and requires more research to confirm. That's because it's unknown exactly how big a role T cells play in fighting COVID-19 — T cells are just one part of a complex menagerie of molecules and cells that makes up our immune system.