The Delta coronavirus variant, which devastated India and forced the UK to delay lifting its remaining coronavirus restrictions, is now on the rise in the US. What that means for you will depend on whether you are fully vaccinated and where you live.
Experts say we may be about to see the emergence of “two Americas” of COVID: one with high rates of vaccination where the Delta coronavirus variant poses little threat, and the other with low levels of vaccination that will be vulnerable to renewed deadly surges. That divide is driven in large part by partisan politics, with vaccination rates highest in liberal cities and lowest in conservative strongholds across the Deep South and in rural areas across the nation.
“I call it two COVID nations,” Peter Hotez, a vaccine researcher at Baylor College of Medicine in Houston, told BuzzFeed News.
Wherever there are low rates of vaccination, the virus will continue to circulate and mutate, increasing the risk that new, more dangerous variants will emerge. With vaccination across most of the world lagging far behind the US, the Delta variant is likely to be followed by others.
The Delta variant, also known as B.1.617.2, was first discovered in India in late 2020 and is thought to have driven that country’s devastating surge in COVID-19, which began in March. It has since spread to more than 80 countries worldwide, including to the US — where the CDC on Tuesday officially designated it a “variant of concern.”
Data from Public Health England indicate that the Delta variant is between 40% and 60% more transmissible than the Alpha variant, also known as B.1.1.7. First identified in the UK and now the most common variant in the US, the Alpha variant is in turn much more transmissible than earlier forms of the coronavirus.
So far, the available vaccines seem to be offering good protection against most variants. But the Delta variant seems able to escape partial immunity to the coronavirus. Although people who are fully vaccinated still seem to be well protected, those who have only been given one shot of a two-dose vaccine remain more vulnerable.
A study in the UK found that two doses of the Pfizer/BioNTech vaccine were 88% effective against developing a case of COVID with symptoms from the Delta variant — not much different from the 93% efficacy seen against the Alpha variant. But after just one dose, the vaccine was only about 33% effective against the Delta variant, compared to more than 50% against Alpha. It’s unclear how effective natural immunity from a prior infection will be in protecting people against the Delta variant.
There are also hints that the Delta variant may cause more serious disease. A study of cases in Scotland published this week found that the risk of hospital admission with the Delta variant was roughly doubled compared to people infected with the Alpha variant.
“This is a nasty virus,” John Moore, a virologist at Weill Cornell Medical College in New York, told BuzzFeed News.
With the Delta variant now thought to account for more than 90% of new infections in the UK, and with cases and hospitalizations rising once again, Prime Minister Boris Johnson announced on Tuesday that he will delay the removal of remaining coronavirus restrictions in England, originally planned for June 21, by at least four weeks. (Scotland, Wales, and Northern Ireland set their own health rules, but have made similar moves.)
In the US, the Delta variant now seems to be spreading more quickly than the Alpha variant at a similar stage in its climb to dominance, according to data from outbreak.info, a coronavirus tracking project run by researchers at Scripps Research in La Jolla, California.