Thank you for visiting nature.com. You are using a browser version with limited support for CSS. To obtain
the best experience, we recommend you use a more up to date browser (or turn off compatibility mode in
Internet Explorer). In the meantime, to ensure continued support, we are displaying the site without styles
Angie Stapp read the letter that her son, Ryder, had sent from San Quentin State Prison several times. “I think it’s just a matter of time before everyone catches it,” he wrote, as COVID-19 ripped through the jail.