People who have been infected with the Omicron variant of SARS-CoV-2 or any of the above are reasonably well protected against the new variants BA.4 and BA.5.
At the moment it is difficult to follow the variants of SARS-CoV-2, the virus that causes covid, although infections continue, although with less severity than at the beginning of the pandemic. As reported by magazine Nature, the new Ömicron BA.4 and BA.5 subvariants are able to evade human immune defenses better than any of their predecessors.
However, recent research shows that prior infection with another variant (such as alpha, beta, or delta) still offers some protection against reinfection with BA.4 or BA.5. Protection against reinfection is even greater if there is a previous infection with omicron. This is the conclusion of a study in which researchers examined all cases of Covid 19 in Qatar produced since the beginning of the wave of infection of BA.4 and BA.5.
The work, published as a preprint and not yet peer-reviewed, is part of a larger investigation into “how different immunities combine,” says study co-author Laith Abu-Raddad, an epidemiologist at Weill Cornell Medical College in the US. Qatar.
Each person has a different immunity history depending on when and with what they were vaccinated against Covid-19 and contracted the disease during the pandemic. This pathway gives each person a different immunity to infection. Knowing how these different immune responses interact in a person is very important for the future of the pandemic, according to the researchers.
To find out to what extent the previous infection protects against the two subvariants of Omicron, scientists analyzed Covid-19 cases recorded in Qatar between May 7, 2022 – when BA.4 and BA.5 first entered the world. country – and July 4, 2022. The team found that infection with a pre-Ómicron variant prevented reinfection with BA.4 or BA.5 with 28.3% effectiveness, while previous infection with Ómicron conferred increased protection for up to 79.7% of individuals.
The time elapsed between the first and second infection also influences. Several studies, including one by the same team in Qatar, have shown that natural immunity to Sars-CoV-2 wanes over time. This may influence why an Omicron infection is more protective, as this variant appeared in late 2021 and the time since the original infection is much shorter.
Despite the results, the researchers warn that Covid is everywhere and “can easily regenerate new variants”.
REFERENCE
Protection of natural SARS-CoV-2 infection against reinfection with Omicron BA.4 or BA.5 subvariants
