Omicron variants 'more likely' to evade antibodies from vaccines, prior infections: Study

A recent study has suggested that Omicron subvariants BA.4 and BA.5 appear to evade antibody responses among both categories of people-- those who had prior COVID-19 infection and those who had been fully vaccinated and boosted. The new data was released by researchers at Beth Israel Deaconess Medical Center of Harvard Medical School. Although vaccine producers are developing revised shots that could trigger a greater immune response against the variants, COVID-19 inoculation is still anticipated to offer significant protection against serious illness.

According to new research published in the New England Journal of Medicine, the levels of neutralising antibodies that a prior infection or immunisations generate are significantly lower against the BA.4 and BA.5 subvariants compared to the original coronavirus.

"We observed 3-fold reductions of neutralising antibody titers induced by vaccination and infection against BA4 and BA5 compared with BA1 and BA2, which are already substantially lower than the original COVID-19 variants," Dr Dan Barouch, an author of the paper, informed in an email to CNN.

BA.4 and BA.5 viruses were more likely to evade antibodies: Research

According to Dr Barouch, the findings also indicate that these new Omicron subvariants will probably be able to trigger outbreaks of infections in people who have both natural BA1 and BA2 immunity and high vaccine immunity levels; "However, it is likely that vaccine immunity will still provide substantial protection against severe disease with BA4 and BA5," he added. 

The recently released findings reinforce separate studies conducted by researchers at Columbia University. They recently discovered that, as compared to other Omicron subvariants, the BA.4 and BA.5 viruses were more likely to evade antibodies from the blood of individuals who have taken a complete course of vaccination and booster shots. This increased the chance of vaccine-breakthrough COVID-19 infections.

BA.4 & BA.5 variants likely to dominate COVID-19 transmission

The researchers at Columbia University also stated that their findings indicate a larger risk for reinfection even in those who had some preexisting immunity to the virus. According to data released by the US Centers for Disease Control and Prevention on June 21, BA.4 and BA.5 are believed to have been the cause of 35% of new COVID-19 infections in the United States last week, up from 29% the week before. 

Meanwhile, the European Centre for Disease Prevention and Control stated that BA.4 and BA.5 variants are spreading at a rapid pace and are likely to dominate COVID-19 transmission in the US, UK and the rest of Europe within the next few weeks.  

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