It appears the B.1.1.7 coronavirus variant first identified in the UK is slightly deadlier as well as being more transmissible than older variants. However, thanks to improved treatments, the risk of dying if you get infected could well still be lower than it was during the UK鈥檚 first wave of the pandemic last March.
鈥淭he additional mortality from the new variant is concerning,鈥� says Graham Medley at the London School of Hygiene & Tropical Medicine (LSHTM). But the main reason why so many people are dying now is the high number of infections, he says.
鈥淚f you want to reduce the number of deaths, you have to reduce the incidence. That reduction in incidence is the critical thing,鈥� he says.
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There is now strong evidence that the B.1.1.7 variant is around 50 per cent more transmissible than other variants. In every place it has reached that does enough sequencing to be able to monitor the prevalence of variants, it is outcompeting others.
Determining whether any variant is deadlier than another is much harder, given that there are far fewer coronavirus-related deaths than infections. It remains unclear whether the P.1 variant in Brazil and the B.1.351 variant from South Africa are any deadlier than previous variants. South Africa in the hardest-hit regions compared with its first wave, but attributes this to increasing pressure on the healthcare system.
To find out if B.1.1.7 is deadlier, researchers in the UK looked at what happened to around a million people who tested positive for the coronavirus. Of these, around 100,000 were very likely to have had B.1.1.7, based on so-called S gene dropouts seen in tests.
The researchers compared people infected with B.1.1.7 to matched controls who had other variants. In addition to matching people鈥檚 age, sex and ethnicity, the researchers also attempted to account for the fact that hospitals in some areas were busier than others and might not have been able to provide the same standard of care.
Four independent teams , using various methods and ways of controlling for confounding factors. All concluded that people infected with B.1.1.7 have a higher risk of dying, with two teams finding around 30 per cent increase, one a 65 per rise and one a 90 per cent increase.
鈥淎ny way that you do it, you get an estimate that is very similar,鈥� says John Edmunds, also at the LSHTM. Although these estimates may not seem that similar, a coronavirus variant could theoretically be 500 or even 5000 per cent deadlier.
A more transmissible virus is worse than a deadlier virus, says Edmunds. 鈥淯nfortunately, it appears this [variant] might be both.鈥�
While this sounds alarming, the findings should be seen in perspective. The overall risk of dying if infected remains very low. During the first wave, the infection fatality rate was around 1 in 100 in rich countries. It is thought to have fallen significantly since then as we have got better at treating covid-19.
鈥淭reatments have been improving,鈥� says Peter Horby at the University of Oxford, who chairs the UK鈥檚 New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG). 鈥淭hat may well offset any differences in this new variant.鈥�
What鈥檚 more, for those individuals who have had one or two doses of a vaccine, the risk of dying will be even lower still. So these findings are no cause for panic, but they are a reminder of how important it is that we all redouble our efforts to avoid becoming infected and infecting others.聽If outbreaks are allowed to rage unchecked, more people could yet die than have already, even in countries with a high proportion of vaccinated people.
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