New COVID-19 omicron subvariants are becoming more dominant in New York and nationwide, and appear to be more infectious than previous versions.
Experts said they’re not surprised because the subvariants are similar to previous versions of omicron. It's unclear whether the new subvariants will be more virulent and whether they are linked to a recent uptick in COVID-19 cases and hospitalizations on Long Island.
“Viruses evolve all the time,” said Danielle Ompad, a professor of epidemiology at the New York University School of Global Public Health in Manhattan.
“A classic example is the influenza [flu] virus," Ompad said. "The reason we have a new vaccine from year to year for influenza is because the virus changes.”
WHAT TO KNOW
- The COVID-19 omicron subvariants EG. 5 and FL. 1.5.1 make up an increasing share of COVID-19 cases.
- The subvariants appear to be more infectious than previous subvariants. COVID-19, like other viruses, constantly evolves.
- It’s unclear whether the recent rise in COVID-19 cases and hospitalizations on Long Island is linked to the spread of the new subvariants.
The new subvariants, EG. 5 and FL. 1.5.1, have accounted for an increasingly larger share of COVID-19 cases in New York and across the country, while XBB. 1.5, which had been the most dominant for months, is becoming less common, according to Centers for Disease Control and Prevention data for the two weeks ending Saturday.
The new subvariants “are not dramatically different” from other omicron subvariants, said Dr. Bruce Farber, chief of public health and epidemiology for Northwell Health.
“We’ve gotten used to seeing these variants come and go,” he said.
Farber said it’s unclear whether EG. 5 or FL. 1.5.1 are helping cause the increase in COVID-19 cases and hospitalizations.
Such hospitalizations on Long Island doubled between late June and late July but have since leveled out. There were 131 COVID-19 hospitalizations Islandwide on Monday and 130 on July 26, state health department data shows. Statewide, hospitalizations are up more significantly.
Case numbers on the Island also continue to rise. There were 1,279 officially reported COVID-19 cases for the week ending Monday, up from 976 for the week ending July 27, and 538 for the week ending June 27. Experts say those numbers are a huge undercount, because most test results aren’t reported to the government, and many people don’t test.
The percentage of COVID-19 tests coming back positive was at a seven-day average of 12% as of Monday, compared with 8.4% two weeks earlier.
Subvariant numbers also aren’t complete, because so few COVID-19 samples undergo genomic sequencing, said Dr. Sharon Nachman, chief of pediatric infectious diseases at Stony Brook Medicine. Genomic sequencing is how scientists determine which subvariants are infecting people.
Nationwide, the EG. 5 subvariant had the largest number of cases: an estimated 17.3%, as of the two weeks ending on Saturday. In the region that includes New York, New Jersey and Puerto Rico, EG. 5 was the second most common variant, at 16%. The most dominant was FL. 1.5.1, at 20.7%. Yet because of so few samples undergoing genomic sequencing, the regional numbers in particular could be either significantly higher or lower than the estimate.
It appears that the latest subvariants lead to similar symptoms as other versions, such as fever, sore throat, sneezing and coughing, Nachman said.
“We’re not seeing untoward or unusual COVID symptoms,” she said.
Scientists are developing a new vaccine booster shot that may be available in the early fall. It is targeted at XBB. 1.5.
Farber said XBB. 1.5 is similar to subvariants like EG. 5, so the new booster will be more effective against new subvariants than previous vaccines.
“There’s never going to be a time when we can get a vaccine that’s active against the current circulating variant because by the time they make the vaccine, there will be a different circulating variant,” he said.
Ompad, of the New York University School of Global Public Health, said the uptick and new subvariants should cause people at higher risk for severe COVID-19, and those in close contact with them, to consider whether to take more precautions, such as mask-wearing and avoiding crowds.
“It’s not time to panic, but we should still be paying attention,” she said. “Every time someone says COVID is over, I just kind of groan.”