Are new COVID variants — called ‘FLiRT’ — spreading in California? A UC doctor explains
Two new COVID-19 variants are rapidly spreading across the United States — including in California.
Dr. Peter Chin-Hong, a professor and doctor specializing in infectious disease at the University of California, San Francisco, said recent data shows the new strains, KP.1.1 and KP.2 — more commonly known as “FLiRT” variants — have escalated quickly since March.
“(FLiRT) is likely more transmissible, because it’s rising up the charts,” Chin-Hong said. “Not only in terms of absolute numbers but the speed at which it is rising.”
To know more about the spread of the FLiRT variants in California, we asked Chin-Hong the following questions:
- How many cases are in California?
- What are the symptoms?
- Will COVID vaccines protect against it?
- Why are the new strains called “FLiRT”?
How quickly is ‘FLiRT’ spreading across California?
In late March, Chin-Hong said the FLiRT variants made up about 3.9% of all COVID-19 cases.
As of May 11, KP.2 numbers have surged to 28.2% and KP.1.1 has escalated to 7.1% nationwide.
Although state-specific data is not available, he said these numbers mirror the rapid spread of the variants across California.
“There’s always a lag from when numbers are reported to what’s actually happening in the community, so the numbers are probably higher than that,” Chin-Hong said.
As of May 10, data from the California Department of Public Health show COVID-related deaths in California were at 0.8%, which was a 0.3% increase from the previous week. The seven-day test positivity rate went up by 0.7% from the previous week, and is currently at 2.7%.
What are the symptoms of the new COVID variants?
Chin-Hong said variations in symptoms between the FLiRT variants and the original COVID-19 strain have not yet been identified.
Symptoms of the FLiRT are similar to the other COVID-19 variants, including:
- Fever or chills
- Cough
- Shortness of breath or difficulty breathing
- Fatigue
- Muscle or body aches
- Headache
- New loss of taste or smell
- Sore throat
- Congestion or runny nose
- Nausea or vomiting
- Diarrhea
Though symptoms can vary between individuals, Chin-Hong said older adults are more likely to experience severe symptoms.
“Age is a big factor,” he said. “Almost 95% of hospitalizations are from older individuals and those who have not yet updated their vaccinations.”
Will COVID vaccines protect me against variants?
“The newest vaccine works really well” to protect yourself from FLiRT, Chin-Hong said.
The latest vaccine was released last fall. Vaccines are consistently updated to the latest strain of COVID to help people avoid severe disease and hospitalization, Chin-Hong said.
Individuals aged 6 months and older are eligible to stay up to date with COVID-19 vaccines, according to the California Department of Public Health.
Though officials are still working to update the vaccine to the previous COVID-19 strain, JN.1, Chin-Hong said there will be a new vaccine by this fall.
“That composition hasn’t been decided yet, but I think the U.S. is going to see what happens with FLiRT and likely recommend something more closely aligned with what’s currently circulating,” he said.
Where does the ‘FLiRT’ nickname come from?
“It’s just something to make the variants more memorable,” Chin-Hong said. “FLiRT is just easier to remember.”
The nickname comes from the technical names used for the mutations of KP.1.1 and KP.2.
According to the Infectious Disease Society of America, the nickname was generated for the technical mutations, represented by the F, L, R and T.
“Then, they just put the ‘i’ to make it more eye-catching,” Chin-Hong said.
This story was originally published May 15, 2024, 3:34 PM.
