Do we need booster shots to fight Omicron? Experts divided

New evidence is leading some scientists to recommend booster shots, due to worries about the Omicron COVID-19 variant.

As researchers learn more about the Omicron variant of COVID-19, some say that booster shots are looking like an increasingly good idea to help fight the pandemic.

“If there was no Omicron in the picture, I think that two doses would have been sufficient for us,” said Sabina Vohra-Miller, founder of Unambiguous Science, a health information organization, although health authorities “strongly” recommend Canadians 50 and older receive the booster to protect against Delta.

“Now that Omicron is in the picture, making sure that Canadians are protected against this variant is going to be important.”

The tipping point is a set of new studies that seem to show that the Omicron variant is better able to evade the protection provided by two doses than previous COVID-19 variants.

On Wednesday, in the first official statement from vaccine manufacturers on the likely efficacy of their shot against Omicron, BioNTech and Pfizer said that two vaccine doses resulted in significantly lower neutralizing antibodies but that a third dose of their vaccine increased the neutralizing antibodies by a factor of 25.

Blood obtained from people that had their third booster shot a month ago neutralized the Omicron variant about as effectively as blood after two doses fought off the original virus first identified in China, the companies said.

Meanwhile, a preliminary study published by researchers at the Africa Health Research Institute in South Africa on Tuesday also said Omicron could partially evade protection from two doses of the Pfizer/BioNTech vaccine and suggested a third shot might help fend off infection. The study has not been peer-reviewed.

There is no significant data yet on how vaccines from Moderna, Johnson & Johnson and other drugmakers hold up against the new variant but they are expected to release their own data within weeks.