Researchers from the Scripps Research Institute have found that B-cells after having a common cold coronavirus react with SARS-CoV-1 and SARS-CoV-2.

The study found that the antibody in question reacts not only to SARS-CoV-2, which causes COVID-19, but also SARS-CoV-1, which causes Severe Acute Respiratory Syndrome (SARS).

Source: Study identifies antibody from common cold infection that reacts to COVID – The Jerusalem Post

Those who previously had a common cold coronavirus may have useful response against SARS-CoV-2. (I prefer to read the original journal article, not the press report or press release, however, Nature Communication was inaccessible this morning.)

Interesting question: If the above is correct, it seems a way of controlling the spread of SARS-CoV-2 would have been to give people a common cold coronavirus in order to develop effective antibodies?