New Delhi: The BA.5 Omicron subvariant is deemed to be immune to vaccine and prior infection. What is more concerning is that it can re-infect COVID patients within weeks.
According to global experts, the new variant, along with BA.4, is driving the fresh surge in coronavirus infections in countries like India, the US, the UK, Italy and China.
For the first two years of the pandemic, it was seen that anyone infected with a COVID variant got a natural immunity boost by developing antibodies for the infection, thereby protecting the person for the next few months.
The BA.5 strain, however, seems to be different. It also seems to be the most highly transmissible variant till date, IANS reported.
“The main reason this variant has become the predominant one is that it is able to evade previous immunity,” said Dean Blumberg, chief of Paediatric Infectious Diseases at the University of California, Davis, Children’s Hospital.
“What we are seeing is an increasing number of people who have been infected with BA.2 then getting re-infected after four weeks,” said Andrew Roberston, chief health officer in Western Australia.
“So maybe within six to eight weeks they are developing a second infection, and that’s almost certainly BA.4 or BA.5,: he added.
A recent study published in the Science journal said that Omicron is a ‘poor natural shield’ against the infection, even in triple-vaccinated patients.
Researchers at Imperial College, London, termed BA.5 as an ‘especially stealthy immune evader’.
“Not only can it break through vaccine defences, it looks to leave very few of the hallmarks we’d expect on the immune system – it’s more stealthy than previous variants and flies under the radar, so the immune system is unable to remember it,” said Professor Danny Altmann, of Immunology and Inflammation department at Imperial College.
