There’s a reason why people are still at risk of catching SARS-CoV-2 months after recovering from COVID-19, and it has something to do with how the virus evolved from the time the pandemic started.
It’s common for everyone to think that they have gotten immune to the virus after battling its disease once. But pecialists clarified that due to the variations in the newer strains, it’s very likely for COVID-19 survivors to contract the virus again.
People who caught the disease before the arrival of omicron developed an 84% lower risk of reinfection, especially in the months right after battling the virus, as per NPR.
However, the subvariants that came after omicron changed the way transmissions work. With the newer mutations in the virus, SARS-CoV-2 has become more transmissible and very good at evading immunity, whether from prior infection, vaccination, or both.
The newer omicron subvariants have become capable of evading protection afforded by earlier non-omicron versions of the virus. This makes it possible for former patients to catch the newer subvariants even if they had the original omicron variant before.
It is also important to note that protection from a past infection wanes over time. Hence, those who battled COVID-19 before are still susceptible to reinfection a few months later.
In February, researchers found that COVID-19 reinfections were rising due to the emergence of newer strains with more mutations than the previous virus versions. They insisted that reinfections should be less severe than primary infections.
The latest data on COVID transmissions seemed to agree with what the researchers said. Though the newer strains are more transmissible and less susceptible to vaccines, they cause less severe illness and fewer deaths, especially among the vaccinated, according to The New York Times.
“Both natural infection and vaccination seem to provide good protection against severe outcomes in most individuals,” Juliet Pulliam, the director of the South African Centre for Epidemiological Modelling and Analysis, told NPR.
Repeat infections are not preventable, so experts have been urging everyone to focus on strengthening their immunity through vaccination. For formerly hospitalized COVID-19 patients, getting the two-dose mRNA vaccines would give them at least 35% protection from subsequent hospitalizations. Getting a booster would increase this to 68%.