As the world grapples with the highly contagious and deadly Delta variant, the debate is heating up over whether vaccines alone can stop the Covid-19 pandemic . It is clear that vaccines can help to reduce deaths, as seen in a recent study by the British Office for National Statistics. It looked at the 51,281 deaths in Britain caused by Covid-19 in the first half of this year, finding that 640 of those who died had been fully vaccinated. That compares to 50,000 unvaccinated people who died. While the study did not say how many of those deaths were caused by Delta, the variant has been rapidly spreading in Britain since early June. It has also been rapidly spreading around the globe, challenging the assumption that a vaccination rate of 70 per cent of the population – a global target US President Joe Biden is reportedly about to propose – will bring an end to the pandemic. Earlier this month, the World Health Organization ’s Europe chief Hans Kluge cast doubt on whether vaccines alone can stop it, saying new strains would continue to emerge. The speed at which the virus is mutating has also prompted scientists to call for more realistic expectations of what vaccines can achieve. If the vaccines cannot stop transmission, the virus will continue to mutate and new variants will continue to emerge. That means Covid-19 could end up like the flu – meaning it is here to stay and it will keep mutating, with new vaccines or booster shots required while a broad-spectrum jab targeting multiple variants is developed. Peter Sands, executive director of advocacy group the Global Fund, last week said that while vaccines were still the best weapon, they could not stop the spread of the disease quickly as the vaccination rate in developing countries was simply too low – just 2 per cent of the population in some places. “There’s no scenario in which we’re going to be able to accelerate vaccination deployment fast enough to be able to arrest the upsurges from Delta,” Sands said. Instead, he said there should be more focus on treatment, oxygen supplies and rapid testing. His comments echo what scientists have long said – that vaccines are not silver bullets and a more comprehensive strategy to fight the pandemic is needed. Covid-19 vaccines have helped to reduce pressure on health care systems around the world, but we might have to accept that they may not be enough.