The newest COVID variants circulating in 2025 are not causing more severe illness than earlier Omicron strains. The overall trend since the Delta wave has been toward higher transmissibility but lower rates of hospitalization and death. That pattern continues with the current crop of variants, though some are better at dodging immunity from past infections and vaccines.
What’s Circulating Now
As of early 2026 CDC tracking data, the variant labeled XFG accounts for roughly 23% of U.S. cases, making it the most common single lineage. No single variant dominates the way Delta or early Omicron once did. Instead, several Omicron-descended sublineages compete for dominance, each with slightly different mutations that help them spread or evade immunity. This fragmented landscape is itself a sign that the virus is evolving in smaller steps rather than making the dramatic jumps seen in 2021 and 2022.
Severity Compared to Earlier Waves
The clearest way to measure “worse” is to look at what happens when people end up in the hospital. During the Delta wave, about 15 out of every 100 people hospitalized primarily for COVID died. That number dropped to 13 during early Omicron and fell to roughly 5 during later Omicron periods. ICU admissions followed the same downward curve: 76% of those who died during Delta had been in the ICU, compared to 57% during later Omicron.
Several factors drive this improvement. Population-wide immunity from repeated infections and vaccination has given most people’s immune systems a head start. The virus itself, across the Omicron family, tends to replicate more efficiently in the upper airways and less aggressively in the lungs compared to Delta. Nothing about the current variants reverses that trend.
Transmissibility Keeps Climbing
Each new subvariant tends to spread a bit faster than the one before it, which is how it becomes dominant in the first place. For context, the original Omicron variant had a basic reproduction number (R0) above 3, already far higher than earlier strains. Alpha was 50% to 75% more transmissible than the original Wuhan strain. Delta was roughly twice as transmissible as Wuhan. Omicron leapfrogged them all.
Current variants gain their edge less through raw transmissibility and more through immune evasion. Small mutations in the spike protein allow the virus to partially sidestep antibodies from your last infection or vaccine dose. This means you can catch COVID again, but it doesn’t mean the resulting illness will be worse. For most people, prior immunity still protects against severe outcomes even when it fails to block infection entirely.
How Well Immunity Holds Up
Research published in Nature found that people who had been infected multiple times with different Omicron subvariants developed broader, more potent antibodies. Those with two different Omicron infections were more resistant to newer lineages like JN.1 compared to people who’d only been infected once. However, the most antigenically distant subvariants, such as KP.3.1.1 and XEC, could still partially escape even this broader immunity.
The 2024-2025 updated COVID vaccine provides moderate protection. CDC data from September 2024 through January 2025 showed the updated shot was about 33% effective at preventing an emergency department or urgent care visit for COVID among adults 18 and older. For immunocompetent adults 65 and older, effectiveness against hospitalization was 45% to 46%. For older adults with weakened immune systems, that figure was about 40%. These numbers are modest but meaningful, especially for preventing the most serious outcomes.
Long COVID Risk Has Dropped
One of the more reassuring trends involves long COVID. A study of healthcare workers found that 42% of those infected with the original ancestral strain developed long-lasting symptoms. That fell to 36% with the Alpha variant and dropped to 16% with Delta or Omicron infections. Vaccination made a significant difference too: people who had received three vaccine doses were less likely to develop long COVID regardless of which variant infected them. While the risk hasn’t disappeared, it’s substantially lower than it was during the first two years of the pandemic.
Symptoms Look Familiar
The CDC’s current symptom list for COVID includes fever or chills, cough, shortness of breath, sore throat, congestion or runny nose, loss of taste or smell, fatigue, muscle aches, headache, nausea, vomiting, and diarrhea. The agency notes that symptoms can shift with new variants and may differ depending on vaccination status. In practice, many people describe current COVID infections as resembling a bad cold or mild flu, with sore throat and congestion being especially common. Loss of taste and smell, once a hallmark of earlier strains, occurs less frequently with Omicron-lineage variants.
Treatments Still Work
The main antiviral used for outpatient COVID treatment remains effective against current variants. A cohort study of 156 participants found that while resistance mutations were occasionally detected, particularly in immunosuppressed patients, there was no evidence of widespread antiviral resistance at the population level. Resistance mutations that did appear tended to be low-frequency and temporary. For most people who qualify for antiviral treatment, starting it early in the course of illness still reduces the risk of severe disease.
Children and High-Risk Groups
COVID can still hit certain groups hard. Among children hospitalized for COVID between 2022 and 2024, nearly 40% met criteria for severe disease and 1 in 4 required ICU admission. The children most at risk were those with underlying conditions. For kids under 2, chronic lung disease and cardiovascular conditions roughly doubled the risk of severe outcomes. For children 2 and older, chronic lung disease, diabetes, and neurologic disorders were the strongest risk factors. Immunosuppressive conditions were present in about 8% of hospitalized children overall, with that percentage rising to 15% among older teens.
These numbers reflect the reality that while COVID has become milder on average, it hasn’t become harmless for everyone. The virus still poses the greatest threat to people with weakened immune systems, chronic health conditions, and advanced age, regardless of which specific variant is circulating.
Do Rapid Tests Still Detect It?
Rapid antigen tests continue to work for current variants. Research comparing test sensitivity across Omicron and Delta found that while Omicron samples produced slightly less antigen relative to viral RNA, the tests still detected the virus at similar rates when antigen levels were comparable. The mutations that differ between variants mostly occur in the spike protein, while rapid tests target the nucleocapsid protein, which changes less dramatically. If you’re symptomatic and test negative, testing again 24 to 48 hours later remains good practice, as antigen levels may simply not have peaked yet.