Yes, there are new strains of COVID-19 circulating right now. The virus continues to evolve, and the dominant variant in the United States as of spring 2026 is XFG.1.1, which accounts for roughly 32% of all sequenced cases. It’s part of a broader family of XFG lineages that together make up the majority of infections. These strains descended from the JN.1 Omicron lineage and carry a distinct set of mutations that help them spread more easily among people with existing immunity.
Which Strains Are Circulating Now
CDC genomic surveillance for the four-week period ending April 11, 2026, shows a landscape dominated by XFG lineages. XFG.1.1 leads at 32%, followed by the parent XFG lineage at 13%, and XFG.14.1 at 8%. Several other XFG offshoots (XFG.6, XFG.2.5.1, XFG.10.4, XFG.23.1.3) each represent smaller slices. Combined, the XFG family accounts for well over half of all circulating virus.
Outside the XFG group, a handful of other lineages are still in the mix. PQ.17, PQ.2.8.1, and PQ.2.1.6 together account for roughly 18% of cases. NB.1.8.1 makes up about 5%, and newer recombinant lineages like XFY and XFZ are each around 3 to 4%. The World Health Organization currently lists XFG and NB.1.8.1 as Variants Under Monitoring, meaning they’re being watched for signs of increased risk but haven’t triggered the highest alert level.
What Makes XFG Different
XFG carries a long list of spike protein changes compared to earlier Omicron subvariants. Key mutations include changes at positions that affect how well the virus latches onto human cells and how effectively it dodges antibodies from past infections or vaccination. Notably, XFG has mutations at positions 346, 444, 445, 456, 487, and 493 on the spike protein, all of which sit in or near the region that antibodies typically target. This clustering of immune-evasion mutations is the main reason XFG has outcompeted older lineages.
Throughout the pandemic, this pattern has repeated: the virus accumulates changes in the spike protein that reduce the effectiveness of existing antibodies, giving the new lineage a growth advantage. XFG follows the same playbook, just with a fresh combination of changes built on the JN.1 backbone. For most people, this means reinfection is possible even if you’ve had COVID before or been vaccinated, though prior immunity still provides meaningful protection against severe illness.
Symptoms to Expect
The symptom profile for current strains remains broadly similar to what people experienced with earlier Omicron variants. Common symptoms include fever or chills, cough, sore throat, congestion or runny nose, fatigue, muscle aches, and headache. Some people also experience shortness of breath, loss of taste or smell, nausea, vomiting, or diarrhea. The CDC notes that symptoms can vary with new variants and with vaccination status, but no dramatically different symptom pattern has emerged with XFG compared to its predecessors.
For most vaccinated or previously infected adults, current infections tend to resemble a bad cold or mild flu lasting about one to two weeks, though some people experience lingering fatigue beyond that window.
How Well Vaccines and Treatments Work
The 2024-2025 updated COVID vaccine, designed around the JN.1 lineage, provides moderate protection against the strains circulating now. CDC data from September 2024 through January 2025 showed the updated vaccine was 33% effective at preventing emergency department or urgent care visits among adults 18 and older, and 45 to 46% effective at preventing hospitalization in immunocompetent adults 65 and older. For immunocompromised older adults, effectiveness against hospitalization was about 40%. These numbers reflect real-world performance against JN.1 descendants like KP.2, KP.3, and XEC, which are closely related to today’s XFG lineages.
Those percentages may sound modest, but they represent meaningful reductions in the chance of ending up in the hospital, particularly for older adults. Protection against severe disease has consistently held up better than protection against mild infection throughout the pandemic.
On the treatment side, antivirals still help with recovery speed. In two large randomized trials (one in the UK, one in Canada) running through September 2024, vaccinated high-risk adults who took antivirals recovered significantly faster: median recovery was 14 days versus 21 days in the UK trial and 6 days versus 9 days in the Canadian trial. Viral levels also dropped more quickly with treatment. However, the trials found no clear reduction in hospitalization or death among vaccinated adults, likely because those rates were already very low (under 1.5%) in both treatment and non-treatment groups. Antivirals are most worth considering for older adults, people with weakened immune systems, or anyone who needs to recover quickly.
Rapid Test Accuracy With New Strains
Home rapid antigen tests still detect current variants, but their sensitivity has important limitations. Compared to the gold-standard PCR test, rapid tests pick up only about 47% of infections overall. That number rises to 56% on days you’re experiencing symptoms and jumps to 77% on days you have a fever. If you have no symptoms at all, sensitivity drops to just 18%.
Compared to viral culture (which measures whether you’re actually contagious rather than just carrying detectable virus), rapid tests perform better: about 80% sensitivity overall and 94% on days with fever. The practical takeaway is that rapid tests are most reliable starting around day two or three after symptoms begin, and they’re especially accurate when you have a fever. A negative rapid test on the first day of a sore throat doesn’t rule much out. If you’re at high risk for severe illness, a PCR test from a healthcare provider gives a more reliable answer and can help determine whether antiviral treatment makes sense.
What This Means Going Forward
COVID continues to circulate year-round with periodic waves, and the virus keeps generating new lineages. The shift from PQ and NB variants to XFG dominance happened over just a few months, which is typical of how quickly the competitive landscape changes. Vaccine formulations will likely continue to be updated, as they are for the flu, to better match whatever is circulating.
For most people, the practical picture hasn’t changed dramatically: current strains cause illness that ranges from mild to moderate in the vast majority of vaccinated or previously infected adults, rapid tests work best a few days into symptoms, and staying up to date on vaccinations remains the simplest way to reduce your risk of a serious outcome.