New Omicron sub-variants can trigger new COVID-19 wave: Study
Scientists in South Africa have found that new Omicron subvariants—BA.4 and BA.5—are capable enough to evade immunity and trigger a new COVID-19 wave, Reuters reported. They did, however, provide some optimism for vaccinated persons since their study found such individuals had better protection against the virus. Notably, Omicron's BA.4 and BA.5 sublineages were included in the World Health Organization's (WHO) monitoring list last month.
- Omicron is believed to have given rise to the global surge in COVID-19 infections lately.
- It is a heavily mutated variant that is highly contagious that can evade immunity from prior infection or vaccination.
- Since being first detected in South Africa in November 2021, Omicron had reportedly spread to more than 100 countries around the globe within just three months.
The new study—conducted by scientists from different South African institutions—found that BA.4 and BA.5 subvariants were capable of escaping immunity from prior infection. They analyzed blood samples of 39 participants previously infected with Omicron (when the variant was first detected last year). Among these, 15 participants were vaccinated—eight with Pfizer's shot and seven with J&J's vaccine—while the other 24 individuals were not immunized.
According to the study, when unvaccinated blood samples were exposed to BA.4 and BA.5, an eight-fold drop in antibody production was observed compared to the original BA.1 Omicron lineage. However, blood samples from immunized individuals showed only a threefold drop, it said. "The vaccinated group showed about a fivefold higher neutralization capacity... and should be better protected," Reuters quoted the study as saying.
The BA.4 and BA.5 Omicron subvariants are believed to be responsible for the majority of new cases in South Africa and have three mutations from the BA.2 Omicron sublineage. The number of mutations in these Omicron subvariants is, however, less compared to the more than 50 changes between the Omicron variant and the first virus strain discovered in China's Wuhan.
According to experts and researchers, a fifth COVID-19 wave may hit South Africa earlier than predicted. They blamed the BA.4 and BA.5 subvariants for the sustained rise in the cases in the country. Notably, only 30% of South Africa's 60 million population is fully immunized against the disease. This indicates the new Omicron subvariants can trigger a new infection wave, considering the neutralization escape.