Is B.1.1.7 Covid-19 variant more deadly? It may be associated with increased risk of death, suggests report
However, the evidence is preliminary and more studies are needed to make firm conclusions, say experts
The new Covid-19 variant, which was first discovered in the UK, may be deadlier than other strains of the virus. It may be linked with a higher degree of death, suggested UK’s Prime Minister Boris Johnson. "In addition to spreading more quickly, it also now appears that there is some evidence that the new variant - the variant that was first identified in London and the southeast - may be associated with a higher degree of mortality,” said Johnson. He, however, noted, that evidence continues to show that the coronavirus vaccines being currently used “remain effective both against the old variant and this new variant.”
Johnson’s announcement was based on a report from the country’s New and Emerging Respiratory Viruses Advisory Group (NERVTAG). The data are preliminary and found that among a subset of patients, there appeared to be an increase in mortality in those who were infected by the UK variant, called B.1.1.7, compared with other variants. “There is a realistic possibility that VOC B.1.1.7 is associated with an increased risk of death compared to non-VOC viruses,” stated the analysis.
Viruses constantly change through mutation, and new variants of a virus are expected to occur over time. Scientists are working to learn more about how easily they might spread, whether they could cause more severe illness and whether currently authorized vaccines will protect people against them.
It is widely accepted that the B.1.1.7 variant is more contagious: it spreads more easily and quickly than other variants. But scientists have previously said it does not appear to be more harmful. The US Centers for Disease and Prevention (CDC) have so far maintained that at this time, there is no evidence that the variant causes more severe illness or increased risk of death.
The CDC also recently suggested that the UK variant could be the predominant strain in the US by March. As of January 22, 195 cases of the B.1.1.7 lineage have been reported to the CDC. This includes 72 in California, 50 in Florida, and 22 in New York, among other states.
Dr Patrick Vallance, UK’s chief scientific adviser, elaborated on the evidence. “If you took a man in their 60s, the average risk is that for a thousand people who got infected, roughly 10 would be expected to unfortunately die with the virus. With the new variant, for a thousand people infected, roughly 13 or 14 people might be expected to die. So that’s the sort of change for that sort of age group, an increase from 10 to 13 or 14 out of a thousand and you will see that across the different age groups as well, a similar sort of relative increase in the risk,” he explained.
However, Vallance emphasized that the data regarding mortality levels are “not yet strong.” “I want to stress that there’s a lot of uncertainty around these numbers and we need more work to get a precise handle on it, but it obviously is a concern that this has an increase in mortality as well as an increase in transmissibility,” he added.
What are experts saying?
According to Rowland Kao, the Sir Timothy O’Shea professor of veterinary epidemiology and data science at the University of Edinburgh, while recent research indicates that the variant is controllable via existing measures, these results on deaths imply that “burden in hospitals will continue to be high requiring a more prolonged period of restrictions.”
Ian Jones, professor of virology at the University of Reading, said the NERVTAG study supporting the enhanced death rate attributed to variant B1.1.7 “is at pains to stress that the data is limited and the conclusions preliminary.” He, however, cautioned that an increased case fatality rate is certainly possible with a virus that has upped its game in transmission.
“But grim as it sounds, whether the fatality rate is 1% or 1.3% doesn’t really change the fact that for a minority of people this is a very dangerous virus that is best avoided. That is achieved by strict adherence to lockdown measures and a willingness to take the vaccine as soon as it is offered. That the variant is as susceptible to vaccine-induced immunity as the parental virus means its circulation should fall as vaccine coverage increases providing hope that the threat it poses is limited overall,” explained Jones.
Lawrence Young, virologist, and professor of molecular oncology at the Warwick Medical School, stressed that one needs more information before jumping to firm conclusions.
Stating that the conclusion about this probable increased lethality comes from analyses made by several different groups, Paul Hunter, a professor in medicine at the Norwich School of Medicine, University of East Anglia, noted that there is quite a bit of difference in the estimated increased risk of death between the different analyses. “Most but not all show increased risk of death. This is a really disappointing finding and will certainly have implications for how we manage the epidemic over coming months,” he stated.