Studying the effects of long COVID

Since contracting COVID-19 back in January 2021, Ken Todd has never made a full recovery, making him one of the millions who suffer from "long COVID."

"In everyday conversation people say, 'Hey, how are you?' Or in emails, 'Hi, hope all is well.' And those conversations and those questions are really hard for me to answer."

CBS News' chief medical correspondent Dr. Jonathan LaPook asked, "What do you answer?"