A lot still remains to be understood about the new variants of coronavirus currently wreaking havoc across the globe, but scientists have recently taken to questioning some of the more alarming aspects with respect to the virus mutations. Till recently, it was believed that the new variants of the coronavirus were more virulent (up to 70 per cent higher transmissibility), but not more deadly or dangerous. Now, the British government's chief scientific advisor has said there is some evidence that the new virus breed first identified in southeast England carries a higher risk of death than the original strain. Patrick Vallance told a news conference that “there is evidence that there is an increased risk for those who have the new variant”. He said the increased risk for a 60-year-old man appeared to be from about one death per 1,000 infections to about 1.3 or 1.4 per 1,000. But, Vallance stressed that “the evidence is not yet strong" and more research is needed.
British Prime Minister Boris Johnson concurred. He said that early evidence suggested that the variant may be more deadly. Based on preliminary data briefing by scientists at the New and Emerging Respiratory Virus Threats Advisory Group (NERVTAG), Johnson admitted that it would seem the new variant was deadlier but stressed that the two vaccines being administered in the UK—Pfizer/BioNTech and Oxford/AstraZeneca—are effective against all variants.
Maria Van Kerkhove, the World Health Organisation’s technical lead on COVID-19, said studies were underway to look at the transmission and severity of new virus variants. She said so far “they haven't seen an increase in severity” but that more transmission could lead to “an overburdened health care system” and thus more deaths. But Vallance said scientists are concerned that variants identified in Brazil and South Africa could be more resistant to vaccines, adding that more research needs to be done. Britain has recorded 95,981 deaths among people who tested positive for the coronavirus, the highest confirmed total in Europe.
The UK is currently in a lockdown in an attempt to slow the latest surge of the coronavirus outbreak. Pubs, restaurants, entertainment venues and many shops are closed, and people are required to stay largely at home. The number of new infections has begun to fall, but deaths remain agonisingly high, averaging more than 1,000 a day, and the number of hospitalised patients is 80 per cent higher than at the first peak of the pandemic in the spring.
Viruses mutate, and more strains are expected
It is normal for viruses to acquire small changes or mutations in their genetic alphabet as they reproduce. Ones that help the virus flourish give it a competitive advantage and thus crowd out other versions. In March, just a couple months after the coronavirus was discovered in China, a mutation called D614G emerged that made it more likely to spread. It soon became the dominant version in the world.
Now, after months of relative calm, “we’ve started to see some striking evolution” of the virus, biologist Trevor Bedford of the Fred Hutchinson Cancer Research Center in Seattle wrote on Twitter last week. “The fact that we’ve observed three variants of concern emerge since September suggests that there are likely more to come.”
One was first identified in the United Kingdom and quickly became dominant in parts of England. It has now been reported in at least 30 countries, including the United States. Soon afterward, South Africa and Brazil reported new variants.
Biggest threat of reinfection
Some lab tests suggest the variants identified in South Africa and Brazil may be less susceptible to antibody drugs or convalescent plasma, antibody-rich blood from COVID-19 survivors — both of which help people fight off the virus.
Health officials also worry that if the virus changes enough, people might get COVID-19 a second time. Reinfection currently is rare, but Brazil already confirmed a case in someone with a new variant who had been sickened with a previous version several months earlier.
According to a paper in Science magazine, the surge in cases in Manaus, Brazil, was an example. It was estimated months before that three-quarters of the city’s inhabitants had already been infected with SARS-CoV-2, the pandemic coronavirus—more than enough, it seemed, for herd immunity to develop. Reported Science: “Variants that could do an end run around the human immune response. Such “immune escapes” could mean more people who have had COVID-19 remain susceptible to reinfection, and that proven vaccines may, at some point, need an update.”
-Inputs from agencies
