Concerns are growing over two new sub-variants of Covid-19 that have been sending infection rates skyrocketing in the UK, raising fears other countries could soon see resurgences in cases as well.
Discovered in South Africa in January and February respectively, the strains known as BA.4 and BA.5 are effectively the grandchildren of the omicron variant of the coronavirus that spread around the world in late 2021 and has three mutations in spike proteins that allow them, it is feared, to retrain their attack on human lung cells.
This means they have more in common with the earlier, more dangerous Alpha and Delta variants than the highly transmissible but milder Omicron, which targeted upper respiratory tissue.
Possibly, these mutations could also allow the subvariants to evade antibodies from previous infections or vaccinations, thus overcoming immunity.
Preliminary data collected by Professor Kei Sato of the University of Tokyo in Japan seems to indicate so, prompting the virologist to comment: “Overall, our research suggests that the risk of [these] The global health Omicron variants, particularly BA.4 and BA.5, are potentially better than the original BA.2.”
Professor Sato’s experiments show that the variants replicate more efficiently in the lungs than Omicron, while further experiments in hamsters suggest that BA.4 and BA.5 can cause more severe diseases.
The World Health Organization has also been examining the two sub-variants since April to see whether they are more contagious or more dangerous than their predecessors and has now included them in their watch list.
In mid-May, the European Center for Disease Prevention and Control labeled BA.4 and BA.5 as “variants of concerns”.
What has raised particular concerns in recent weeks has been the sharp rise in UK infections following four days of celebrations to honor the Queen’s platinum jubilee of 2 figures the following week.
The latest UK data records 75,367 new cases in the seven days leading up to June 15, up almost 39 per cent on the week.
The number of Covid deaths remains very low but hospitalizations have started to rise, doubling in England from 421 on May 26 to 842 on June 15.
While immunity is high in Britain, with 87.1 per cent of the population having received two doses of the vaccine and 68.5 per cent of people having received a booster shot, the public has largely behaved as if the pandemic has been through since the last unpopular Boris government Johnson had never happened. The restrictions were lifted a month ahead of schedule on February 24, giving up face masks, distancing and normal life resuming.
However, it has been more than six months since the last major booster jab drive before Christmas and the New Year and immunity could be waning, potentially leaving more patients in need of professional care and possibly even dying, either now or later in the year that flu season begins.
“There’s a disconnect between the actual course of infections … and people’s decision not to take very many precautions,” warned John Swartzberg, professor emeritus of infectious diseases and vaccinology in the School of Public Health at the University of California-Berkeley The daily beastobserved the situation in the UK and suggested that their terms could easily be replicated across the Atlantic.
Should the equivalent subvariant surge arrive in North America, moving east to west like all previous Covid waves, the US will be much less well immunized, with only 66.8 percent of the American public fully vaccinated and only 47 percent cent, who has received a booster vaccination.
Currently, BA.4 and BA.5 account for about 21 percent, or one in five new cases in the United States, according to the Centers for Disease Control and Prevention, with the first being identified on the American coast in New York in April.
But experts now expect that proportion to increase significantly in the coming weeks, another unwelcome reminder that the pandemic is far from over, much as we might wish for it.
How dangerous the new subvariants really are, whether they can fuel passed antibodies and cause serious disease, or whether our accumulated immunity persists remains to be seen.