The news and information about the SARS-Cov-2 coronavirus delta variant (cDv) is currently swamping us. Since the viral story is very fluid as the virus keeps us guessing, we’ll try to distill some points about it at this juncture. The labels being used for the mutations as they arise follow the Greek alphabet. Hence, the U.K. variant as the first change from the initially known or “ancestral” strain from Wuhan, China, is alpha. The second variant arose in South Africa, and is beta. The third one popped up in Brazil, and is gamma. And the latest (and not greatest), which emerged in India, is delta.
The cDv is currently causing medical havoc in over 85 countries, including the U.S. We have the blessing of some vaccinations being done in most parts of the country, which is not the case globally where they often lack vaccines. It is also not the case in sparse U.S. areas. CDv accounts for 18 % of cases in Colorado, Montana, the Dakotas, Utah, Missouri and Wyoming. It was previously believed that it caused 25% of infections nationwide. As this is being written, the CDC newly estimates the cDv is causing 51% of cases in the U.S. and 80% in certain Midwestern states. In India and the U.K., it is the dominant strain. It is now in all 50 U.S. states.
It is thought to be the most transmissible of all variants to date, 60% more so than the alpha variant, which, in turn, is 50% more transmissible than the Wuhan strain.
From a June 16, 2021 National Geographic article, “Freely circulating viruses, especially coronaviruses and influenza viruses” — which both have their genetic codes as RNA instead of DNA — “mutate frequently and randomly due to copying errors introduced as they replicate in their human host cells. Some mutations enable the virus to evade antibodies; some enhance its ability to infect a host cell; other go unnoticed since they yield no survival benefits, or even weaken them.”
“If a mutation gives a virus a fitness or reproductive advantage, that mutation tends to evolve independently around the world. The virus carries a cluster of mutations that helps it infect human cells more easily. One, at the location 452 of the spike protein, which binds to the human cell receptor ACE2 as its path of entry into cells, makes it more transmissible. Another at spike protein position 681 makes cell invasion easier. This mutation is becoming common in all COVID viruses globally. A third mutation at spike position 478 enables the virus to escape from weaker neutralizing antibodies.”
“When you have all these mutations, then you start to see a difference in infectivity”, says Ravindra Gupta, clinical microbiology professor at the University of Cambridge, who has shown in an unpublished study how these variants can cause greater or worse disease. There are other indications pointing that way as well. Several references cite the fact that now 99% plus of viral deaths are in unvaccinated people. In breakthrough infections in those vaccinated the symptoms are not as severe or lasting. The more variants like this spread, especially in unvaccinated individuals, the more these viruses mutate and pick up mutations that allow for more efficient antibody escape.
The vaccines seem to be less effective in preventing infections by the cDv and others, but still make a difference! In a new study from Israel the Pfizer vaccine still prevented 93% of severe disease. President Biden recently said, “Folks, the delta variant is spreading among young people between 12 and 20 years old in the U.K. If you’re young and haven’t got your shot yet, it is really time.” Dr. Jonathan Reiner of George Washington University said, “What I would say to young people is that COVID-19 doesn’t have to kill you to wreck your life. … People will continue to die until we vaccinate everybody. … Vaccination is the ticket to get your life back.”
The contentious issue of mask wearing has re-emerged with the cDv rising. Last week Los Angeles County where cases are increasing substantially is recommending that “everyone, regardless of vaccination status, wear masks indoors in public places as a precautionary measure.” Israel has reinstated masking requirements in public indoor spaces and large outdoor gatherings following hundreds of new COVID-19 cases being detected. The WHO echoes those sentiments, while the CDC in the U.S. is less concerned. (Who would think that experts disagree!?) But, as Dr. Ezekiel Emanuel of the University of Pennsylvania asks, “We don’t know the consequences of even a mild infection. Is a little more insurance from wearing a mask worth it? Yes.”
Even some Republicans are acknowledging vaccines are vital. The Republican governor of West Virginia, Jim Justice (what a name for a politician!), has just said people hesitant about receiving a vaccination are “not thinking right” and warned they are playing a “death lottery.” Arkansas governor, Republican Asa Hutchinson, has been and is imploring people to get vaccinated as the state had a 51% increase in cases over the last few weeks.
The above is a distillation lot of current articles about cDv. The virus is not done with us yet, even though we wish it were. Wishing won’t work. Getting shots will, perhaps along with judicious mask use, as so many Asian countries have done for decades. Meanwhile, we’ll just keep distilling to find the proof. I’m not sure if this column was 80 or 100 proof …
Dr. Bures, a semi-retired dermatologist, since 1978 has worked Winona, La Crosse, Viroqua, and Red Wing. He also plays clarinet in the Winona Municipal Band and a couple dixieland groups. And he does enjoy a good pun.