In the US, the novel Covid-19 variant EG.5 is currently in the lead. According to the most recent estimates from the US Centres for Disease Control and Prevention, EG.5 is responsible for roughly 17% of new Covid-19 cases nationwide, compared to 16% for the next most prevalent lineage, XBB.1.16.
EG may sound like a completely other strain of the virus, but it is actually an offshoot of the Omicron family’s XBB recombinant strain. Furthermore, unlike the original Omicron strain, it indicates another minor modification to the virus rather than a significant evolutionary leap.
It bears an additional mutation to its spike at position 465 when compared to its father, XBB.1.9.2. This mutation has already been found in other Covid-19 varieties. Scientists are unsure of the specific additional abilities it gives the virus, but because many of the new XBB offspring have adapted it, variant hunters are paying closely.
The 465 mutation is found in around 35% of Covid-19 sequences published globally, including FL.1.5.1, a Covid-19 whose prevalence is increasing in the Northeast, indicating that it may have some sort of evolutionary benefit over earlier iterations. Additionally, EG.5.1, an offshoot of EG.5, now has a second mutation added to the spike. That one is also gaining ground quickly.
In order to determine how resistant these variations have become to the antibodies we have to defend against them, Dr. David Ho has been studying them in his lab at Columbia University. According to Ho, a professor of microbiology and immunology, “both are only slightly more resistant to neutralising antibodies in serum of infected and vaccinated persons.”
Clinically, he claimed, it doesn’t appear that these varieties are producing any different or more severe symptoms than the viruses that came before them.
Dr. Eric Topol, a cardiologist at the Scripps Translational Research Institute, stated that this XBB series “basically has some more immune escape compared to the ones that were precedents in this XBB series.” It has a benefit, which is why it is spreading over the world.
Beyond the US, EG.5 is expanding swiftly in countries including China, Japan, Ireland, France, and the UK. On Wednesday, the World Health Organisation changed its classification from a variant under surveillance to a variant of interest, indicating that the organisation believes it should be followed and further investigated.
There is no evidence to show that this particular strain is what is causing the rise in cases, ER visits, or hospitalisations, but the variant has become more common in the US at the same time.
Instead, epidemiologists believe that this increase is being driven by human behaviour. They cite instances where extreme heat forces more individuals indoors for air conditioning, aiding in the spread of the infection. People are leaving their usual social networks throughout the summer to travel, which spreads diseases to new victims. In many areas of the country, classes are starting up again, and parents are aware that children don’t just bring home their homework from school.
However, there are reasons to believe that this wave of cases won’t be as severe, according to Dr. Anne Hahn, a postdoctoral associate in the Yale School of Public Health’s Department of Epidemiology of Microbial Diseases.
Because of the extremely low baseline and substantial population immunity, it is unlikely that there will be a significant spike anytime soon. But it’s yet unclear what these new variations will do in the winter,” she said.
Data from Biobot Analytics show that virus levels found in wastewater in August were almost the same as those seen in March. Dr. Dan Barouch, an immunologist and virologist at Harvard University in Boston, said: “I do expect that there will be widespread infections, and I would expect that those widespread infections would generally be mild.”
Naturally, those who are at a high risk for serious illness must continue to exercise caution. Topol claims that this fall’s upgraded Covid-19 booster, which will be directed against the XBB variation, should be a very near match to the varieties currently in circulation, including EG.5. He anticipates that it will provide strong protection — provided that regulatory agencies can provide it to patients in time.
Manufacturers of vaccines have stated that the new doses should be ready in a few weeks, but CDC Director Dr. Mandy Cohen has predicted that the updated vaccination will be accessible in October since it needs approval from the CDC and the US Food and Drug Administration.
The availability of boosters last autumn was a full month earlier. “Why is this taking so long?” you ask. said Topol. “The whole idea of mRNA is that you could pivot quickly and you’d have it ready within a couple of months.”
According to Topol, the vaccination is especially crucial for elderly people and people with compromised immune systems since they no longer have access to potent monoclonal antibodies that could be helpful if a Covid-19 infection worsens. Why the procedure appears to be taking longer than last year is unclear. When asked how soon it will assess the autumn vaccines, the FDA did not react right away.
The US cannot afford to delay the deployment of the Covid-19 vaccine, according to Topol. A group of variations with modifications that let them to adhere to cells more firmly are expected to overtake EG.5, according to him, making them even more contagious. He is concerned that they could potentially be more significant. Things are escalating, so it should be released right away, he said. “We need it right now.”