COVID-19 reinfection more common in people 65 and older, study finds

‘Natural protection cannot be relied on,’ researchers wrote

COVID-19 ReinfectionIs More Common in OlderPeople, Study Says.A study published in medical journal‘The Lancet’ has found that older peopleare more prone to COVID-19 reinfection.The data used was drawn from Denmark’snational testing strategy, which saw four million peopletested for COVID-19 over the course of 2020. .Overall, COVID-19 reinfection was found tobe a rare occurrence in the population.Only .65 percent of patientstested positive a second time afterpreviously being infected duringDenmark’s initial COVID-19 waves. .However, the study made an alarming discoveryregarding protection against reinfectionamong various age groups.People over 65 years old were found to haveonly 46 percent protection against reinfection.This is in comparison to younger people whowere found to have 80 percent protection. .Steen Ethelberg of Denmark’s Statens SerumInstitut says the study “makes clear” how important itis to establish policies that protect the elderly. .Since older people are also more likelyto experience severe disease symptoms,and sadly die, our findings make clearhow important it is to implement policiesto protect the elderly during the pandemic, Steen Ethelberg, via Reuters

Surviving COVID-19 is not a guarantee you won’t get it again, scientists say, and the chance of reinfection is much higher if you’re age 65 and older.

In a population level observational study, researchers in Denmark collected data from the Danish Microbiology Database and analyzed infection rates during during the country’s second surge of the COVID-19 epidemic, which was September 1 through December 31.

The scientists then compared those findings to infection rates during the first surge, which was March-May 2020.

The study found that of the 11, 068 people who tested positive for COVID-19 during the first surge, only 72 were positive during the second surge.

Overall, protection against reinfection was 80.5%. There was little difference between male and female protection rates (78.4% of males and 79.1% of females).

The study also found protection against reinfection was 79.3% three to six months after recovery, and 77.7% at more than seven months.

One group benefited much less, however, the researchers found. Those ages 65 and older enjoyed only a 47.1% rate of protection.

“Our finding that older people were more likely than younger people to test positive again if they had already tested positive could be explained by natural age-related changes in the immune system of older adults, also referred to as immune senescence,” the scientists wrote. “Our analysis highlights the need to protect older people against reinfection with SARS-CoV-2 by vaccination, physical distancing measures, and personal protective equipment, such as facemasks, regardless of previous infection status.”

“Furthermore,” the group wrote, “our data indicate that vaccination of previously infected individuals should be done because natural protection cannot be relied on.”

The study was published last week in the medical journal Lancet.