Covid-19 reinfections are rare, but seem more common for people 65 and older, study finds From CNN’s Jen Christensen Covid-19 reinfections are relatively rare, but it’s more common for people 65 and older to get infected more than once, according to a study published Wednesday in the Lancet medical journal. Scientists from Denmark’s Department of Infectious Disease Epidemiology and Prevention noted that most people who have had Covid-19 seemed to have protection from reinfection for about six months. When they looked at the demographics of who was getting infected again, it was mostly people 65 and older. They looked at the reinfection rates among 4 million people during the second surge of Covid-19 from September through Dec. 31, and compared that to the infection rates during the first surge between March and May. Ultimately, they found that of the 11,068 people who tested positive during the first surge, only 72 tested positive again during the second.