With some researchers predicting the Delta COVID variant may become the dominant strain, the Centers for Disease Control and Prevention has heightened its designation of it to a “variant of concern.”
The new designation for this variant, which was first discovered in India, follows research that shows the mutation is more transmissible and may be able to escape the body’s immune response. A small number of cases in Connecticut have been attributed to this variant, according to researchers.
“I think it’s more motivation to get vaccinated,” said Dr. Michael Parry, chair of infectious diseases for Stamford Health. “It’s sort of a wait-and-see proposition with all of these variants, there’s a lot of things we don’t know,” he added.
The variant is believed to spread among people more easily than the original strain of coronavirus that led to the global pandemic, and more easily than the Alpha variant first detected in the U.K., according to research from the U.K. that was cited by the CDC.
The strain is one of several variants first detected in India believed to have fueled that country’s deadly second wave of the virus this spring.
There have been 32 cases of the Delta variant confirmed in Connecticut through genomic sequencing of positive test kits, according to the most recent data compiled by the Yale School of Public Health, Jackson Labs, the state Department of Public Health and others. The variant comprised 6.5 percent of samples sequenced in the previous week, up by about 3.2 percentage points, according to the data from June 10. A new report is expected later this week.
In comparison, the Alpha variant comprised almost 57 percent of samples taken, but the data also showed the prevalence of Alpha dropped by nearly 11 percentage points over the previous week.
The data also shows the Gamma variant, a strain of the virus first found in Brazil also known as P.1, trending upwards. The variant made up nearly 11 percent of the variants sequenced, up 2.7 percentage points from the week before.
“What will happen in CT and the (U.S.)? Delta will likely become dominant,” tweeted Nathan Grubaugh, who heads the Yale School of Public Health’s efforts to sequence the virus.
“How we prevent Delta (and other variants) from causing another (wave) is pretty simple. Get vaccinated,” he said.
Researchers believe the Delta variant may be able to evade the body’s immune response, either from vaccination or from treatments of monoclonal antibodies given to COVID-19 patients. So far, research in the U.K. has shown the Pfizer-BioNTech vaccine is still highly effective.
“I think the good news, it seems like the vaccines are protective,” said Dr. David Banach, head of infection prevention at UConn Health. He also emphasized the variant is another reason for those who have not yet been vaccinated to get their shots.
While he said the potential for the variant to be transmitted to someone whose immune system is compromised, and for whom the vaccines might offer less protection, he was more concerned about the highly transmissable variant’s ability to pass between people who aren’t yet vaccinated.
As of Tuesday, just under 53 percent of the U.S. population have received at least one dose of a vaccine, according to CDC data. In Connecticut, and much of the Northeast, the number is higher, with a little more than 65 percent of the population having received at least one dose of the vaccine.
In the U.K., research has shown the variant may now comprise more than 90 percent of the country’s new COVID-19 infections, supplanting the Alpha variant, which is now thought to be the dominant lineage in the U.S.
That has scientists concerned the Delta variant could also become dominant in the U.S., even as states work to vaccinate more people.
“We cannot let that happen in the United States,” Dr. Anthony Fauci said during the White House COVID-19 briefing last week, urging people to get vaccinated and follow through on getting their second shots.
Parry said hospitals still don’t receive data back from the state when they send samples for genetic sequencing on patients with concerning cases — such as severe cases of COVID-19 or breakthrough cases involving vaccinated patients. He said the state Department of Public Health has promised to begin giving them the data to use clinically, but its unclear exactly when hospitals will receive it.
Along with the rest of the country, Connecticut’s COVID-19 metrics have remained low throughout the spring, and like most states, nearly all of the pandemic restrictions have been lifted here.
On Wednesday, the state reported 39 new cases of the illness from 10,187 tests for a daily positivity rate of 0.38 percent. Hospitalizations remained flat at 50 statewide, while two more fatalities brought the official death toll to 8,265.
At Stamford Hospital, only one patient is hospitalized for the virus, Parry said Wednesday afternoon. With the majority of the state’s older population vaccinated, patients hospitalized for COVID-19 are trending younger, and are “predominantly people who are not vaccinated,” he said.