LONDON (Reuters) – Britain will in rare cases allow people to get shots of different COVID-19 vaccines, despite a lack of evidence on the extent of the immunity offered by mixed doses.
In contrast to other strategies worldwide, the government said people could get a mix-and-match of two COVID-19 shots, for example, if the same vaccine dose is not in stock, according to guidelines published on New Year’s Eve. “(If) the same vaccine is not available, or if the first product received is unknown, it is reasonable to offer one dose of the locally available product to complete the schedule,” according to the guidelines.
Mary Ramsay, head of vaccinations at Public Health England, said it would only happen in extremely rare cases, and that the government did not recommend mixing vaccines, which require at least two doses given a few weeks apart.
“We have to do everything we can to give the same vaccine, but where it is not possible, it is better to give a second dose of another vaccine than not at all,” she said.
COVID-19 has killed more than 74,000 people in Britain – the second highest death toll in Europe, and health officials are rushing to deliver doses to end the pandemic as fears grow that the health service could be overwhelmed.
Earlier this week, the government reactivated emergency hospitals built at the start of the outbreak while the ward was full of COVID-19 patients. Britain has been at the forefront of approving the new coronavirus vaccines and is becoming the first country to grant Pfizer authorization. BioNTech and the vaccines AstraZeneca / University of Oxford last month.
Both vaccines are intended to be administered as two shots, with a few weeks apart, but they are not designed to mix together.
The government’s new guidelines said there was “no evidence for the interchangeability of the COVID-19 vaccines, although studies are ongoing”.
However, the advice said that although every effort should be made to complete the dosing regimen with the same vaccine, but that the patient is at “immediate high risk” or as “unlikely to attend again”, they may be given different vaccines.
Britain aroused controversy earlier this week by announcing plans to delay the release of the coronavirus vaccine boost in an effort to ensure more people can be given the more limited protection by a single dose.
Leading American expert in infectious diseases, Anthony Fauci, said on Friday that he did not agree with the British approach of postponing the second dose to 12 weeks.
“I will not advocate for that,” he told CNN. “We’re going to keep doing what we do.”
Reporting by Andrew MacAskill; Edited by Helen Popper