Antibody slide studied
A new study has looked at the decline of antibodies following infection with the COVID Omicron strain.
According to Danish research, there is a rapid decline in Omicron-specific neutralising antibody levels only a few weeks after the second and third doses of the Pfizer vaccine.
Compared to people's antibody responses against Delta, people's Omicron-specific antibody responses declined rapidly from 76.2 per cent at week 4 to 53.3 per cent at weeks 8 to 10 and 18.9 per cent at weeks 12 to 14.
While a third dose boosted this response for at least 8 weeks, between week 3 and week 8, it was still around 5 times lower than the response to Delta.
The researchers say this suggests that additional booster doses may be necessary, particularly in older people; however, they add that the vaccines may still protect against hospitalisation and death through T-cell immunity.