Study indicates that having COVID does not mean future immunity

Having COVID doesn’t guarantee immunity, study of Marine recruits finds Ten percent of Marine recruits who had COVID antibodies got COVID again during basic training. Karen Jowers Marine Corps Times

Have you had COVID? Think you’re immune from it in the future? Think again, according to the results of a new study of Marine Corps recruits.

Ten percent of the recruits whose blood tested positive for COVID-19 antibodies before training were re-infected with COVID while in basic training at Marine Corps Recruit Depot Parris Island, South Carolina.

The findings make a strong argument for healthy young Americans to get vaccinated, according to researchers.

“For our particular population, this is very strong data about why individuals previously infected, regardless of whether they had symptoms or not, should get the vaccine in accordance with DoD policy,” said Navy Cmdr. Andrew Letizia, deputy director of the infectious disease directorate at the Naval Medical Research Center. The doctor is one of the researchers and authors of the study, published in the Lancet Respiratory Medicine Journal Thursday.

Antibodies are proteins made by the immune system to fight infections; it’s uncertain whether young adults who get COVID are at risk of getting it again. NMRC conducted the study along with the Icahn School of Medicine at Mount Sinai to examine how effective antibodies are in preventing future COVID infections.

Recruits with these COVID-19 antibodies had about one-fifth the risk of getting COVID again, compared with those who didn’t have antibodies. While antibodies from previous COVID-19 infection do provide some protection to young adults, it’s no guarantee, the authors stated.

This is the largest study of COVID-19 looking over the long-term, where researchers have followed active-duty members before they got infected, Letizia said. They used data from blood samples and nasal swabs collected from the recruits when they arrived at Parris Island, and over six weeks of observation after they left their two weeks of restriction of movement. ...