by Kyle B. Enfield,The Conversation

Credit: Unsplash/CC0 Public Domain

Avariant of COVID-19 called BA.3.2, which has circulated under the radar since late 2024, is now spreading quickly across the United States. As apulmonary and critical care doctor, I see many patients who are at high risk for severe COVID-19 due tochronic lung disease, as well as patients living withlong COVID. All of them ask me how worried they should be about new variants of the virus.

There's no sign so far that BA.3.2, nicknamed Cicada, is any more dangerous or causes more severe disease than the variants that were circulating in the winter of 2025-26. But because it'ssignificantly different from them, the current COVID-19 vaccine may not be as effective against it.

Where did the BA.3.2 variant come from?

BA.3.2 is descended fromthe omicron variant, which emerged in late 2021.

Compared to the current predominant strains ofSARS-CoV-2, the virus that causes COVID-19, BA.3.2 carries70 to 75 genetic changesin itsspike protein, the part of the virus thathelps it get into cells. The spike protein is also thepart of the virus that vaccines rely ontocoax people's immune systemsintorecognizing the virus.

Researchersfirst identified BA.3.2 in November 2024in Africa. It started its global trek in 2025 andhad made it to 23 countries as of February 2026.

The first U.S. case was detected in atraveler coming into the U.S. in June 2025. Since then, it has been detected in patients and the wastewater systems of 29 states.

Wastewater monitoringis one of the best early methods ofdetecting strain shift, though the number of states submitting wastewater data to the CDC has declined since around 2022, after the height of the pandemic.

What makes BA.3.2 variant different?

All viruses change over time—and the type of virus that causes COVID-19does so especially quickly. Every time the virus copies itself inside a cell, its genetic material mutates. Most of these changes disappear, but occasionally one gives the virus an advantage over other variants, allowing that version to spread.

These changes make it harder for the immune system to recognize the virus.

Think of it like showing up to your 25th high school reunion and seeing people who have put on weight, dyed their hair, and started wearing tinted contacts. You will recognize them, but it might take longer. Had you seen them every month or so for those 25 years, you would recognize them right away.

Similarly, changes to a virus' genetic material also affect how well vaccines work. Vaccines prime people's immune systems by reminding them of what the virus looks like. Scientists design vaccines based on the most common versions of a virus circulating at a given time.

Current COVID-19 vaccinesare made to protect against strains fromthe JN.1 lineage of the virus, which have been themost common strains in the U.S.since January 2024. However, BA.3.2 is the new kid on the block − it's almost a complete stranger to residents of the U.S. It is different enough from the JN.1 strains that the vaccinemay not do as good a jobof priming the immune system against it, allowing it to evade detection.

This doesn't mean you shouldn't get a vaccine—a large body of evidence shows that theyreduce hospitalizations and deaths from COVID-19. But a poorly matched vaccine simply won't recognize the new variant as quickly, which means it takes longer for the immune system to mount its defense.

What dangers does the BA.3.2 variant pose?

Because people's immune systems aren't as good at detecting BA.3.2, this variant may infect people more widely, potentially leading to a spike in COVID-19 cases.

But even though BA.3.2 is spreading quickly, there's no indication that it's any more dangerous or that it causes more severe disease than the COVID-19 variants that have circulated widely over the past few years.

However, especially given that current vaccines may not be as effective against it, protection remains important. That's particularly true for people with chronic health conditions, who can experience severe illness from a COVID-19 infection.

And while the number of people who develop long COVIDhas declined as the virus has changedsince early in the pandemic, it still occurs in aboutthree in 100 cases.

Protecting yourself and your community

People can take these commonsense steps to avoid getting or spreading COVID-19:

This article is republished fromThe Conversationunder a Creative Commons license. Read theoriginal article.

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