Possibility of coronavirus reinfection was a concern since the first reports of people getting sick again in 2020 began to appear – while many people around the world were still isolated. But there has been relatively little data so far on how widespread this phenomenon is.
The first large-scale survey that addressed this question was published in The Lancet this week, and found that the vast majority of people who have had COVID-19 are really protected from getting it again – for at least six months. However, people aged 65 and over are much more likely to have a recurrence of the infection.
The researchers analyzed data from Denmark’s national COVID-19 testing program, which provided free PCR testing to approximately 4 million people living in the country. In general, they found that a very small percentage of the population – 0.65% – experienced reinfection.
For those aged 65 and under, obtaining coronavirus provided approximately 80% protection against reinfection. But for people aged 65 and over, it provided only about 47% protection against COVID-19 recovery, further underscoring how dangerous this disease can be for older adults.
“Because older people are also more likely to have severe symptoms of illness and unfortunately die, our findings clearly show how important it is to implement policies to protect the elderly during a pandemic,” Steen Ethelberg said. the author of the study at the Statens Serum Institute in Denmark, said in a statement. “Given what is at stake, the results highlight how important it is for people to adhere to the measures put in place to keep themselves and others safe – even if they have already had COVID-19.”
“Given what is at stake, the results highlight how important it is for people to adhere to the measures put in place to keep themselves and others safe.”
– Steen Ethelberg, researcher at the Statens Serum Institute in Denmark
What this study means to us (and the future of the pandemic)
Overall, this news is positive, but it also emphasizes the need for continued vigilance. Many factors could still play a potential role in the disease.
The appearance of different variants is one of them. Coronavirus reinfection has become a major concern in recent months, as new variants have begun to circulate around the globe.
A vaccine study in South Africa – circulating a variant that experts fear is more contagious and may make current vaccines less effective – found new infections in 2% of people who had previously been infected with a vaccine. another variant of coronavirus.
The large new study in Denmark did not examine the role of variants in reinfection, given the time period of the research. So it does not give clues as to whether the variants are more likely to come with COVID-19 more than once.
Previous case studies of people who were reinfected were worrying, as they suggested that it might be possible to get sick a second time. Such was the case of a healthy 25-year-old man from Nevada, who tested positive for COVID-19 last spring, recovered, then fell ill again. He asked for hospitalization a second time. But even when the first reports appeared and attracted significant news coverage, researchers were careful to point out the rarity of this result.
As the new reinfection study was not conducted in the United States, it is unclear whether the findings apply in the same way here. But overall, researchers are optimistic that most people receiving COVID-19 will not experience reinfection soon after. And he continues to study immunity, both after infection and after vaccination. It is unclear at this time how long the immunity lasts after a person receives a COVID-19 vaccine.
All this underlines the continuing need for basic preventive measures, even as coronavirus cases begin to decline nationally.
Centers for Disease Control and Prevention recommend that people who have had COVID-19 be vaccinated once they are available, largely because there is little chance that they can become infected again if they come in contact with the virus.
Continuing to wear the mask is also essential because qthe questions remain to the extent that those who have recovered from COVID-19 are able to spread it to others if exposed again. In addition, wearing a mask helps reduce the chances of a person getting the virus more than once.
Earlier this month, the CDC launched new guidelines, saying fully vaccinated Americans can gather safely indoors without wearing masks or social distances, offering a promising look at how restrictions will loosen as more many photos will go into several arms. But for now, it’s a race against the clock to make sure millions of Americans are immunized as variants continue to spread.
Experts are still learning about COVID-19. The information in this story is known or available from the date of publication, but the guidelines may change as scientists discover more about the virus. Please check the Centers for Disease Control and Prevention for the most up-to-date recommendations.