Omicron infection after vaccination may protect against other coronavirus strains, study finds
- South African study says vaccination followed by Omicron infection may stop Delta and other variants, but immune protection not observed in unvaccinated people
- Meanwhile, US researchers suggest breakthrough infection caused by other strains after two mRNA shots won’t prevent Omicron
An Omicron breakthrough infection after vaccination could offer protection against other strains – but that protection was not observed in unvaccinated people, a study in South Africa, has suggested.
In the US, the team from Ohio State University, led by Dr Shan-Lu Liu, examined the neutralising antibody response against the Alpha, Beta, Delta and Omicron variants in 48 health care workers who were vaccinated with either the Pfizer or Moderna mRNA vaccines.
Blood samples were collected before vaccination, after the first dose, and twice after the second dose, according to the paper published in the journal Science Translational Medicine on Tuesday.
The researchers observed a decline in the neutralising antibodies – a predictor of immune protection – from one month to six months after the two doses were given.
All four variants of concern consistently showed lower neutralising antibodies compared to a strain at the early stage of the pandemic, with the Omicron variant having the most pronounced resistance.
