Concern is growing over two new sub-variants of Covid-19 that have spiked infection rates in the UK, raising fears that other countries could soon see a similar resurgence in cases as well.
Known as BA.4 and BA.5, the strains were discovered in South Africa in January and February respectively and are actually the grandchildren of the Omicron variant of the coronavirus, which has spread across the world at the end of 2021, and exhibit three mutations to their spike proteins, which it is feared allow them 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.
Potentially, these mutations could also allow the subvariants to evade antibodies from previous infections or vaccinations and thus overcome immunity.
Preliminary data captured by Professor Kei Sato of the University of Tokyo in Japan seems to indicate this, prompting the virologist to comment: “Overall, our investigations suggest that the risk of [these] The Omicron variants, especially BA.4 and BA.5, for Global Health are potentially superior to the original BA.2.
Professor Sato’s experiments indicate that the variants replicate more efficiently in the lungs than Omicron, while other experiments in hamsters have suggested that BA.4 and BA.5 may lead to more severe disease.
The World Health Organization has also been investigating the two subvariants since April to determine whether they are more infectious or dangerous than their predecessors and has since added them to its watch list.
The European Center for Disease Prevention and Control in turn labeled BA.4 and BA.5 “variant concerns” in mid-May.
What has caused particular concern in recent weeks has been the sharp rise in British infections following four days of festivities honoring the Queen’s Platinum Jubilee from June 2-5, which encouraged increased socializing and duly led to a 43% increase in case numbers the following week.
The latest data from the UK records 75,367 new cases in the seven days to June 15, an increase of almost 39% week-on-week.
Deaths from Covid remain 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% of the population having received two doses of the vaccine and 68.5% of people having received a booster, the public has largely behaved as if the pandemic does not had never happened since the last unpopular government of Boris Johnson. the restrictions were repealed a month ahead of schedule on February 24, ditching face masks and moving away and returning to normal life.
However, it has now been over six months since the last major recall campaign was mounted before Christmas and the New Year and immunity could start to wane which could lead to more patients needing professional care and possibly even to deaths, now or later. in the year when the flu season goes down.
“There’s a disconnect between the reality of how infections happen…and how people decide not to take a lot of precautions,” warned John Swartzberg, professor emeritus of infectious diseases and vaccinology at the University of California-Berkeley School of Public Health. The daily beastobserving the situation in the UK and suggesting that its conditions could easily be replicated across the Atlantic.
If the equivalent sub-variant surge arrived in North America, moving east to west as all previous Covid waves have done, the US would find itself much less immune, at just 66.8% of the American public fully vaccinated and only 47% percent who received a booster.
Currently, BA.4 and BA.5 account for about 21% or one in five new cases in the United States, according to the Centers for Disease Control and Prevention, with the first identified on US shores in New York in april.
But experts now expect that proportion to rise significantly in the coming weeks, another unwelcome reminder that the pandemic is far from over, however much we hope it is.
It remains to be seen how dangerous the new subvariants really are, whether they can fuel transmitted antibodies and cause serious illnesses, or whether our built-up immunity will hold firm.