Following the announcement on Monday that the government has secured early access to 90 million doses of “promising vaccine candidates,” chair Kate Bingham sought to temper the enthusiasm of those who may have thought a breakthrough was imminent. She told Sky News: “We have to be very cautious, because there has never been a vaccine against a coronavirus and there may never be one.”

Bingham is the latest scientist to give the sobering assessment that, despite global efforts, the provision of a successful immunization program against the pandemic is not guaranteed.

Covid-19 is from the coronavirus family, which includes a number of other highly infectious diseases. Noting that there is no vaccine against SARS, another coronavirus, Bingham explained, “There is no vaccine against malaria, against HIV, and these are diseases we know well.” She added that “there is no expectation that this definitely can be done” and it's “unlikely” there will be a single [Covid-19] vaccine that works for everyone.

The prime minister urged the British people not to pin their hopes on the prospect of a vaccine being available this year or next, insisting to claim so would be “an exaggeration,” because he does not himself have “100 percent” confidence. “We’re not there yet,” he concluded.

Nonetheless, one of the leading Covid-19 vaccine development groups is based in the UK. Results of the first phase of human trials carried out by Oxford University scientists revealed on Monday that their coronavirus vaccine is safe and induces an immune response to the disease.

Phase-two testing is already under way in the UK, with 14,000 volunteers, and phase-three testing on volunteers in the Covid-19 high-risk countries of Brazil and South Africa is also taking place.

Professor Sarah Gilbert, co-author of the Oxford University study, said: “There is still much work to be done before we can confirm if our vaccine will help manage the Covid-19 pandemic, but these early results hold promise.”