The data suggests that those who have had the virus should still be vaccinated.
Photographer: Nathan Laine / Bloomberg
Photographer: Nathan Laine / Bloomberg
Sign up here for our daily coronavirus newsletter on what you need to know, and subscribe to our Covid-19 podcast for the latest news and analysis.
Older people are more at risk of re-contracting Covid-19 after recovering from a previous attack of the virus, new research shows.
While most people are unlikely to get the disease again for at least six months, older people are more prone to reinfection, according to results published Wednesday in The Lancet. The study of the test results in Denmark last year showed that those under 65 who had had Covid were about 80% protected from getting it again. Protection fell to 47% for people over 65.
The data suggests that those who have had the virus should still be vaccinated, the authors said. Natural protection cannot be relied on, especially for the elderly are most at risk of serious illness. Denmark’s analysis focused on the original coronavirus strain and did not assess new variants that were believed to be more transmissible.
Why the variants of the mutated coronavirus are so concerning: QuickTake
“Our findings highlight the importance of implementing policies to protect the elderly during the pandemic,” even if they have already had Covid-19, Steen Ethelberg, a senior researcher at the Statens Serum Institute in Copenhagen, said in a statement. . “Our insights can also support policies aimed at broader vaccination strategies and easing lockdown restrictions.”
The study authors analyzed data collected as part of Denmark’s national SARS-CoV-2 testing strategy. More than two-thirds of the population, or about 4 million people, was tested over a period of the first and second waves. The analysis found that only 0.65% of people returned a positive PCR test during both waves. A higher share – 3.3% – achieved a positive result after a previous negative one.
Consistent with findings from other studies, there was no evidence that protection against reinfection decreased within six months, the authors said. However, as the virus was not identified until December 2019, the full period of protective immunity conferred by infection has yet to be determined. It was also not possible to judge whether the severity of symptoms affected a patient’s degree of immunity, they wrote.
“These data are all confirmation, if necessary, that for SARS-CoV-2 the hope of protective immunity from natural infections may not be within our reach and a global vaccination program with highly effective vaccines is the sustainable solution, ”wrote professors Rosemary Boyton and Daniel Altmann of Imperial College London in a commentary related to the study.