The new Covid-19 variant Omicron is thought to be more transmissible and is said to be fuelling an
‘exponential’ rise in South African Covid cases as it displaces the Delta variant. Even the head of the
vaccine maker Moderna, Stéphane Bancel, believes existing vaccines will be less effective against it than they were against the Delta variant.
For this reason, it’s vital people have as high a level of antibodies as possible to protect against severe
disease, says the leading Covid testing expert Dr Quinton Fivelman PhD. This should involve everyone who qualifies receiving newly adapted booster jabs every six to nine months.
Dr Fivelman, the Chief Scientific Officer at London Medical Laboratory, says: ‘It’s good news that the Government has announced a deal for 114 million additional Pfizer and Moderna vaccines for potential use as a fourth jab and beyond. Omicron could reduce the effectiveness of current vaccines, but it is likely that they will still protect against severe disease.
‘What is needed in the longer term is a rolling programme of boosters adapted to cover new strains as they evolve. The arrival of Omicron highlights this. Existing vaccines may not be as targeted against this as previous variants, because they train the immune system against the coronavirus’ spike protein and
Omicron has more than 30 mutations in this protein. However, some antibodies and T cells will still remain effective.
‘Imagine this as a battle: the enemy has a new defence against some of our main weapons, but the number of troops on our side still counts for a lot and will have a big impact on the outcome.
‘New research by the Cov-Boost Trial published in The Lancet shows people who received a Pfizer boost after two doses of AstraZeneca developed antibody levels nearly 25 times higher than controls. Those receiving the Pfizer top-up after receiving two Pfizer shots previously had an eightfold increase in antibodies. Both Pfizer and Moderna boosters also increased the level of T cells, vital in warding off the Omicron variant.