Phill Magakoe/AFP via Getty Images
THE more infectious coronavirus variant from the UK has gone global, causing fears that it could lead to a new wave of infections and deaths around the world in coming months if not brought under control. That brings new urgency to vaccination efforts.
The B.1.1.7 variant has so far been reported in 55 countries. There is no evidence that it is more deadly, nor that it is yet spreading locally outside Europe and North America. But initial studies suggest that it is around 50 per cent more transmissible.
That is actually a bigger problem than if it were more deadly, says Adam Kucharski at the London School of Hygiene & Tropical Medicine.
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A simple calculation illustrates why. Suppose 10,000 people are infected in a city and each infects 1.1 other people on average, the low end for the estimated rate of infection in England now. After a month, 16,000 people would have been infected. If the infection fatality rate is 0.8 per cent, as it was in England at the end of the first wave of infections, it would mean 128 deaths.
With a variant that is 50 per cent more deadly, those 16,000 cases would result in 192 deaths. But with a variant that is 50 per cent more transmissible, though no more deadly, there would be 122,000 cases after a month, leading to 976 deaths.
To halt a surge in UK cases partly due to B.1.1.7, England and Scotland this month joined Wales and Northern Ireland in strict lockdown. By the start of this week, all parts of the UK had brought in tougher travel rules.
Last month, Ireland began a strict lockdown after reporting the fastest growth rate of any country in coronavirus cases.
55
The number of countries with reported cases of the UK variant
One reason was relaxed restrictions in early December, with pubs and restaurants reopening, says Kingston Mills at Trinity College Dublin. But by last week, nearly half of all new cases were due to B.1.1.7. “I think it was a combination of both,” he says.
The B.1.1.7 variant is now spreading locally in other nations in Europe and in some US states.
Given that the US is already hard hit and unlikely to use lockdown-type measures, Angela Rasmussen at Georgetown University in Washington DC says this is a big worry. “When you already have uncontrolled transmission and then you add another variant that is more transmissible, you are going push the healthcare system past its limit,” she says.
Elsewhere in the world, most reported cases of B.1.1.7 are in travellers, says Áine O’Toole at the University of Edinburgh, UK. That means it may not yet be circulating locally and there might be time to keep it out, she says.
Yet many countries may be finding the variant only in travellers because they aren’t doing genetic sequencing for local cases, says O’Toole. Most countries did little sequencing until recently, so B.1.1.7 could be spreading undetected in places.
The spread of the B.1.351 variant from South Africa appears more limited. Though more than a dozen countries have reported cases, it is only known to be transmitting locally in Botswana, Zambia and the UK, says O’Toole. The similar P.1 variant that originated in Brazil has only been found in travellers in Japan so far.
These variants might be dominating in South Africa and Brazil because they seem slightly better at evading the immune response in previously infected people and these countries have had high levels of infections, says Rino Rappuoli at GlaxoSmithKline Vaccines in Italy. If so, the variants will have no transmission advantage in countries with low levels of immunity. But this will alter as vaccination ramps up.
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