LONDON—The U.K.’s bold call to delay giving people a second dose of a Covid-19 vaccine has put it out in front in the race to inoculate the world against the disease.
Behind that decision: a group of 16 scientists who advocated a controversial move to overrule some vaccine manufacturers’ guidelines in order to get more first doses to more people.
The gamble appears to have paid off, with incoming data pointing to durable protection against falling ill after just one vaccine dose. But while some countries, such as Canada, have followed the U.K.’s lead, others including the U.S. are refusing, saying to do so could pose a risk to public health.
The decision by British authorities holds lessons for other countries as they fight to contain the pandemic. Indeed, the dosing debate raises difficult questions about whether some governments and their scientific advisers—for instance in the European Union, where vaccination campaigns are painfully slow—are being too risk averse.
In December, as a highly infectious Covid-19 variant ripped across the U.K., the group of scientists sitting on Britain’s Joint Committee on Vaccination and Immunisation concluded that delaying a second vaccine dose by up to 12 weeks could save lives.