A study of more than 3,000 young Marines in the United States found that those without a history of COVID-19 had a five times higher risk of infection than those previously infected, according to findings published in the journal Lancet Respiratory Medicine.
The study also found that about 10% of young Marines who survived COVID-19 developed a second infection.
“Among 189 seropositive participants, 19 (10%) had at least one positive PCR test for SARS-CoV-2 during the 6-week follow-up (1.1 cases per person per year),” the study found.
Previously infected Marines who were reinfected had lower antibody levels and fewer neutralizing antibodies than previously infected Marines who were not reinfected, the study found.
“Although antibodies induced by initial infection are largely protective, they do not guarantee effective neutralizing activity of SARS-CoV-2 or immunity against subsequent infection,” the study said.
“This analysis was performed as part of the prospective study COVID-19 Health Action Response for Marines (CHARM). “CHARM includes mostly male American seafarers, aged 18-20, after two weeks of unsupervised quarantine at home,” the statement said. .
A separate study published in the Lancet in March found that the majority of people who have had COVID-19 are protected from getting it again for at least six months, but older people are more likely to reinfect than younger people. people. Read more
Our standards: Thomson Reuters’ principles of trust.