While Connecticut’s COVID-19 positivity rate is down to 8.1 percent, experts are concerned about two new variants spreading in the state.

Here’s what you need to know about BA.4 and BA.5, two offshoots of the pesky Omicron variant that has kept the virus more prevalent than expected this spring and summer. The new strains are:

“People who are counting on, ‘I’m free for a couple months now because I got COVID,’ not true,” said Ulysses Wu, MD, chief epidemiologist at Hartford HealthCare.

As of June 3, BA.4 and BA.5 made up about 20 percent of Connecticut’s COVID-19 cases, and are likely to become the dominant strains as summer progresses. The Centers for Disease Control and Prevention says the variants make up at least a quarter of cases nationwide.

Wu said BA.4 and BA.5 could keep positivity rates relatively high in Connecticut during the summer months – at a time when some expected a drop off in cases.

“They will blunt our descent,” Wu said. “That’s probably why we have this saw-tooth pattern — up one day, down one day. I do believe [the variants are] contributing to that to a certain extent.”

Wu said a more severe spike could be in the cards this fall.