Second booster ineffective on general population

Scientists advising the government on coronavirus are against rolling out a second booster shot for the general population, urging authorities to donate surplus vaccines to poorer countries.

In comments to Phileleftheros daily, Dr Christos Petrou, a government advisor on vaccinations, said: “Instead of contemplating rolling out a second booster shot for the general population, Cyprus, just as other western countries, should forward their vaccine surplus to countries which do not have access to vaccines”.

Asked why the fourth dose of a COVID vaccine would not stem the spread of the virus, Petrou said that this has to do with the effectiveness of available vaccines in creating immunity against infection with the Delta and Omicron variants.

“Vaccines are very effective in preventing serious illness and death, with high levels of protection being offered with the booster shot,” said Petrou.

“Several countries, including Cyprus, have decided to roll out the fourth dose to the elderly and people in high-risk groups, such as immunosuppressed people.

“In the United States last week, Pfizer asked the FDA to approve the fourth dose for people over 65.”

However, as he noted, the highly contagious Omicron variant cannot be combatted with frequent vaccinations, and “data on whether a fourth dose of a vaccine would be beneficial for healthy adults is insufficient”.

Israel study

The government advisor referred to a study carried out in Israel amongst health workers vaccinated with a second booster shot.

According to the study, while antibody levels were pushed back to where they were following the first booster shot, this did not prevent an Omicron infection.

In interim findings published in the New England Journal of Medicine, the authors concluded that for young and healthy people, a fourth vaccine provided “slightly more protection than the three doses”.

The situation stressed Petrou, “is dynamic and needs systematic monitoring to identify which groups of the vaccinated are those who eventually end up in the hospital along with the unvaccinated.

“In addition, we need to approach the issue of the fourth dose with caution, since frequent doses with the same antigen will have no additional effect, while they could also have a toll on the immune system”.

Currently, no vaccine targets the Omicron or the Delta variant, adding that he hoped these vaccines would be available by the autumn.

He argued the crucial jab for the general population is the first booster shot, for which authorities should be campaigning to convince people to get.

“I emphasize once again the issue of vaccination justice. “The countries of the West, instead of concentrating on rolling out the fourth jab, should redirect their surplus in vaccines, before they expire, to poorer countries.

“Unless the whole world is protected, no country can feel safe.”