New FLIRT COVID variants could create ‘perfect storm for a wavelet’
The emergence of a new set of coronavirus variants, known colloquially as FLIRT, is sparking concerns about a potential summer uptick in COVID-19 cases after an extended period of calm and a relatively mild winter.
The variants, known as KP.1.1 and KP.2, have recently overtaken JN.1 as the dominant omicron offshoot in the U.S. They now account for 1 in 4 infections nationwide, according to the latest data from the Centers for Disease Control and Prevention.
Although COVID-19 hospitalizations and deaths in California and around the U.S. have reached their lowest point since the pandemic began, the mutations on the FLIRT variants may make them more effective at infecting people, particularly as immunity gained from previous illness or vaccination wanes over time.
“While a full-blown surge this summer is unlikely due to the new variants, more people are going to get sick,” said Dr. Peter Chin-hong, an infectious-disease expert at UCSF. “The increased transmissibility of these new variants, coupled with more people gathering indoors to escape the heat or for travel, creates the perfect storm for a wavelet.”
The CDC said it is tracking the variants to better understand their potential impact on public health, including symptoms they may cause or their ability to evade protection from current vaccines and treatments.
Simultaneously, the agency discontinued its requirement for states to report COVID-19 hospital admissions last month, phasing out one of the most reliable metrics to track the pandemic’s status over the past four years. Instead, the agency will rely solely on wastewater tracking, test positivity rates and deaths to keep tabs on the coronavirus.
“We have less ability to see a rising tide and advise people preemptively about when to get vaccinated and take other precautions,” Chin-hong said. However, he also pointed out that we have reached a stage where we can manage COVID-19 more effectively, and it no longer poses a “catastrophic” risk to the health care system.
Here’s what you need to know about the FLIRT variants and the current state of the pandemic.
What are the FLIRT variants?
The FLIRT variants — KP.2 and KP.1.1 — are offshoots of JN.1.11.1, a descendant of the JN.1 variant that drove most cases this winter. All of them are part of the omicron family. The new strains come with two additional mutations whose alphabetical designations (F and R) are the source of their nickname. Scientists speculate that the mutations could make the variants more infectious.
However, the CDC notes that “while KP.2 is proportionally the most predominant variant, it is not causing an increase in infections as transmission of SARS-COV-2 is low.”
Chin-hong noted that the virus is evolving rapidly, with a new variant rising to dominance approximately every six months, a much quicker clip than other viruses such as influenza or the common cold.
Do vaccines still work against the new variants?
The reformulated COVID-19 vaccine introduced in September was designed to target the omicron subvariant XBB.1.5, which was predominant in early 2023. Although less effective against newer strains, it still protects against severe illness and death. However, only about 22% of adults have received the updated vaccine, significantly lower than for previous COVID shots, leaving many others more vulnerable to infection.
“Right now, we still have COVID-19 patients in the hospital,” Chin-hong said. “I always ask, ‘Did you get the latest COVID vaccine released in the fall?’ Pretty much 100% of the people I saw said, ‘I didn’t get the new vaccine but I got a lot of vaccines before.’ “
Advisers to the Food and Drug Administration will convene in early June to determine the formulation for the upcoming fall vaccine, expected to target JN.1 and its descendants.
What are the symptoms of the FLIRT variants?
The CDC is monitoring infections caused by KP.2 and KP.1.1. Early data suggests that they produce symptoms similar to those caused by JN.1, typically appearing two to 14 days after infection. These symptoms include:
• Sore throat
•Cough
•Fatigue
• Congestion
• Runny nose
• Headache
• Muscle aches
• Fever or chills
• New loss of sense of taste or smell
• Brain fog
•Shortness of breath or difficulty breathing
• Gastrointestinal distress
Chin-hong said he has observed an uptick in cases of diarrhea, which is not unprecedented but “kind of odd.” However, he said there’s no expectation of new symptoms or increased severity of the disease linked to the FLIRT variants.
Should you still test whether you were exposed to COVID-19?
Health authorities continue to advocate using at-home COVID-19 tests, despite the possibility that they may be less sensitive to the newest virus strains. The CDC advises home testing if you exhibit symptoms, or five days after exposure to COVID-19, even if you are asymptomatic. Peoples are encouraged to test themselves over several days if initial results are negative.
Should I taking other precautions?
Although it is no longer mandated, the CDC recommends wearing a high-quality mask in public places when respiratory viruses — and not just SARS-COV-2 — are prevalent in your community. Additionally, the agency suggests wearing a mask when interacting with people at a higher risk of severe illness.
Chin-hong encourages people to get the updated COVID-19 vaccine in conjunction with their annual flu shot in the fall. He suggests timing this before an anticipated winter surge, typically preceding the holiday season, to optimize protection. However, older adults or those with compromised immune systems can receive a booster now and follow up with another dose in the fall.