New Coronavirus Variant KP.2 Becomes Dominant Strain
Key Takeaways
KP.2, a subvariant of Omicron, is now the most common strain of Covid-19 in the United States.
There's no evidence KP.2 causes worse illness than previous Omicron variants. Hospitalization rates remain low.
Existing vaccines and treatments are expected to work against KP.2. New fall vaccines may offer even greater protection.
Home tests remain reliable for KP.2. Isolate until fever-free for 24 hours and symptoms improve, then mask for 5 days. Immunocompromised individuals should consult their doctors.
The Centers for Disease Control and Prevention (CDC) reports a new coronavirus subvariant, KP.2, has become the dominant strain in the United States.
This raises several questions for the public, including symptoms, testing, vaccines, and isolation protocols.
What is KP.2?
KP.2 belongs to a group of Omicron subvariants nicknamed "FLiRT variants" due to specific mutations in their spike proteins. It appears to be displacing previously dominant Omicron subvariants like JN.1.
There is currently no evidence that KP.2 is more contagious or causes more severe illness compared to previous Omicron variants. Hospitalization rates associated with Covid-19 remain low.
Existing vaccines and treatments are expected to be effective against KP.2. The CDC recommends a second booster shot of the original vaccine for those 65 and older.
New and improved vaccines targeting dominant fall and winter variants are expected in the fall, which may offer even greater protection against KP.2 if it remains prevalent.
What are the Symptoms of KP.2 Infection?
KP.2 shares the same symptoms as other Covid-19 variants: runny nose, sore throat, headache, fever, cough, and body aches.
Some people may experience shortness of breath or have underlying conditions heightened by the virus.
These symptoms are not exclusive to KP.2 and can be difficult to differentiate from other viral infections like the flu or common cold.
If you're unsure, take this flu or COVID quiz.
Are Home Tests Reliable for Detecting KP.2?
Rapid antigen home tests remain a convenient screening tool for Covid-19, although less accurate than PCR tests.
There's no indication they're less effective in detecting KP.2 compared to other variants.
Consider taking multiple home tests over several days if symptoms continue or seek PCR testing for confirmation.
How Long Should People Isolate?
The CDC no longer recommends a mandatory five-day isolation period. Instead, individuals diagnosed with Covid-19 should isolate at home until fever-free for at least 24 hours and symptoms improve.
For the following five days, masking and limiting close contact with others are still advised.
Also, while there's no specific guidance yet, the immunocompromised should consult their doctors regarding additional precautions such as masking or pre-exposure prophylaxis (PrEP) with medications to prevent severe illness if they contract Covid-19.