What questions do your kids have about the Covid-19 vaccine?

The UK can expect to have a “portfolio of three or four vaccines” in use by the middle of next year, England’s Chief Medical Officer told lawmakers on Wednesday.

Thousands of people were vaccinated on Tuesday, the first day of the national rollout of the Pfizer/BioNTech coronavirus vaccine. 

Asked by lawmakers when the UK regulator would decide on the Oxford-AstraZeneca vaccine, chief of the Medicines and Healthcare products Regulatory Agency June Raine said she could not provide a firm date for a decision on authorization.

Raine said regulators have “great interest” in how the two dosing regimens produced different efficacies, and if there is a scientific basis to the different immune responses. 

The Oxford-AstraZeneca vaccine showed 90% efficacy in one dosing regimen — when the vaccine was given as a half dose, followed by a full dose at least a month later. It showed 62% efficacy in a second regimen — when two full doses were given to people at least a month apart.

On the issue revaccination, Whitty told lawmakers that the situation may arise where vulnerable people will need to be revaccinated, as it is yet unknown how long protection against the virus can last.

“It might last for a very long time, it might last for […] nine months, I think it’s more likely to be somewhere between those two,” Whitty said. 

Asked what lessons have been learned from the pandemic, Whitty admitted that in the early stages of the pandemic, officials underestimated asymptomatic spread.

“We drew comfort wrongly from SARS,” Whitty said, referring to the respiratory illness brought on by a coronavirus that killed more than 700 people in 2002 and 2003.

“In SARS, the great majority — if not all — of the transmission was from people who were symptomatic,” Whitty said. 

Whitty went on to say that the pandemic could have been managed better in the early stages if “data streams” were more complete on mask effectiveness, lockdown timings and travel quarantines. 

He said that limited testing capacity meant officials hadn’t realized how widespread the virus had become in the UK or across Europe. 

On communicating health guidance to Britain’s minority ethnic groups – who have suffered disproportionately from the pandemic – Whitty acknowledged that officials did not get the messaging right in the early stages, adding that social research was and still is not strong enough.