Hopes for herd immunity from first Covid-19 vaccines may be unrealistic
Evidence suggests the first vaccines will at least stop people developing Covid-19, but it cannot be ruled out that people will still catch it and pass it on to others unnoticed
Frankfurt/London — Governments and officials are voicing hopes that Covid-19 vaccines could bring “herd immunity”, with some calculating that immunising just two-thirds of a population could halt the pandemic disease and help protect whole communities or nations.
But the concept comes with caveats and big demands of what vaccines might be capable of preventing. Some experts say such expectations are misplaced...