THE B.1.1.7 coronavirus variant first spotted in the UK is poised to cause a surge in cases worldwide. In many areas of Europe and North America, the variant, which is more transmissible, is now responsible for most new coronavirus infections.
Globally, since late February there has been a small uptick in coronavirus infections. Before this, case numbers had been falling sharply. The big question is what happens next.
鈥淚n Italy, bars reopened in February and, combined with B.1.1.7, they are seeing a rise in cases鈥�
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鈥淭here will almost definitely be a resurgence almost everywhere,鈥� says Nick Davies at the London School of Hygiene & Tropical Medicine. His suggests that this could include the UK if lockdown measures are relaxed too quickly.
A global surge could also be driven by the B.1.351 variant first seen in South Africa and the P.1 variant initially spotted in Brazil, says Davies.
Others disagree. 鈥淎nother [global] wave due to B.1.1.7 is far from inevitable,鈥� says David Dowdy at Johns Hopkins Bloomberg School of Public Health in Baltimore, Maryland. Other factors are moving in a positive direction, he says. More people are getting vaccinated, the weather is getting warmer in the northern hemisphere and there is a gradual build-up of population immunity.
The B.1.1.7 variant already contributed to a big second wave of cases in the UK in December, forcing the UK government to impose a strict lockdown in England in January. At the start of this wave, the B.1.1.7 variant was responsible for only a small proportion of cases. It now causes 98 per cent of all cases in the UK.
Much the same thing happened in Ireland and Portugal, which also imposed lockdowns as a result.
Now, cases are starting to surge in other countries, including the Czech Republic, Italy, Poland and Hungary. These countries don鈥檛 do much genome sequencing to identify the virus variant detected in new cases, so it , but reports suggest it is .
鈥淚n Italy, bars and restaurants reopened in February and, combined with a high prevalence of B.1.1.7, they are seeing a steep rise in new cases again,鈥� says Tom Wenseleers at the Catholic University of Leuven (KUL) in Belgium.
An ominous pattern is emerging in places doing more sequencing. Although the number of cases due to older variants is falling, the number of cases due to B.1.1.7 is rising exponentially. Where this trend continues, the overall number of cases climbs again.
Belgium, for instance, is seeing an increase in the overall number of cases that is almost entirely due to B.1.1.7, says Wenseleers (see graph, below).
The UK has shown that lockdowns can halt the spread of variants, but in many countries, including Germany, there is pressure to ease restrictions. 鈥淭he main risk would be to reopen too many sectors again at the same time,鈥� says Wenseleers.
Vaccination also works. In Israel, where B.1.1.7 accounts for more than 80 per cent of cases, infection rates are falling fast about one month after a lockdown ended. This is almost certainly because nearly 90 per cent of people aged over 16 have been vaccinated.
Countries such as the US, where a third of the population has had one dose, still haven鈥檛 vaccinated a high-enough proportion of the population to prevent a resurgence of cases in the coming weeks. The vaccination rates in most of Europe are far lower, and will be further slowed now the use of the Oxford/AstraZeneca vaccine has been suspended in several countries.
In most of the rest of the world, vaccination has barely begun and little is known about the prevalence of variants, making it difficult to predict future trends.
