Catching omicron ‘does not protect you against future infection from the variant’

Catching Omicron doesn’t protect people from future infection by the variant, Imperial College has found, scientists saying it explains why cases remain stubbornly high.

Throughout the pandemic, studies have shown that prior infection provides immunity against re-infection with Covid and often protects against other variants as well.

But new research has found that there is virtually no extra immunity boost from getting Omicron, leaving people at risk of contracting the strain again.

The study could help explain why cases continue to rise, despite the fact that a large number of people have now been infected with Covid.

The latest update from the Government’s coronavirus dashboard on June 9 shows that Covid cases in England have risen by 64 per cent over the previous week, while hospital admissions have risen by 33 per cent.

‘Omicron and its variants are great at breaking through’

Professor Danny Altmann of Imperial’s Department of Immunology and Inflammation said: “The message is a bit grim. Omicron and its variants are great at breakthrough but poor at inducing immunity, so we get reinfections ad nauseam and a severely exhausted workforce. “

He added: “Not only can it breach vaccine defenses, it also appears to leave very few of the hallmarks we would expect on the immune system – it’s more stealthy than previous variants and flies under the radar so the immune system doesn’t.” is able to remember.”

In the latest study, the team set out to find out why so many people were reinfected with omicron, often fairly soon after their first attack.

The team analyzed blood samples from UK healthcare workers who received three doses of mRNA vaccine and had different histories of infection to examine antibody, T and B cell immunity.

They found that in people who were triple-vaccinated and had no prior infection, Omicron infection produced an immune boost against earlier variants such as Alpha, Beta, Gamma, Delta and the original ancestral strain, but virtually nothing against Omicron itself.

People who contracted omicron during the first wave of the pandemic and then re-infected also lacked any immune enhancement, an effect the researchers call “hybrid immune suppression.”

“Omicron could further mutate into a more pathogenic strain”

Professor Rosemary Boyton from Imperial’s Department of Infectious Diseases and lead author said: “Omicron infection does not provide a strong boost in immunity against future Omicron reinfection.

“One concern is that omicron might mutate further into a more pathogenic strain or be better able to overcome vaccine protection.

“In this scenario, people who have had Omicron infection would be poorly protected against future infections, depending on their immune imprint.”

The research was published in the journal Science.