With the death toll from Covid-19 in India having reached a staggering 300,000 this week, the spread of a highly transmissible variant first identified on the subcontinent has raised well-founded fears across the world.
In the small number of countries, including Ireland, where mass vaccination programmes are well advanced, concerns have centred on whether the so-called Indian variant might evade the vaccines. There was some good news on that front in recent days when a study by Public Health England found that the Pfizer/BioNTech and AstraZeneca shots were 88 per cent and 60 per cent effective after two doses, respectively. They are likely to be even more effective at preventing hospital admission and death. However, both vaccines were only 33 per cent effective against the variant three weeks after a first dose.
The emergence of the Indian variant and other mutants, combined with vaccine hesitancy, could make herd immunity... much more difficult
That suggests two problems – one short-term, the other long-term. The short-term issue is that countries with active vaccination campaigns will be vulnerable to the Indian variant until such time as a critical mass of the population has received full protection. That may determine how quickly indoor activities can resume.
If the Government meets its target of giving a first dose to 80 per cent of the population by the end of June, then by July it will have at best 50 per cent protection against the UK variant and less against the Indian variant, as Prof Philip Nolan of the National Public Health Emergency Team (Nphet) points out. That means waiting a few weeks longer to open pubs and restaurants could make a big difference to the rate at which the disease spreads.
The longer-term issue is that the emergence of the Indian variant and other mutants, combined with vaccine hesitancy, could make herd immunity – somewhere between 60 and 80 per cent coverage – much more difficult, perhaps even impossible, to attain. For all western governments, the task is two-fold: to get the timing of indoor reopening right so as to deny new variants the chance to spread, and to pull out all the stops to encourage the public to take this life-saving injection.