
The Omicron BA.2 subvariant is tearing across Europe and Asia, with experts predicting it will cause an uptick of cases in the U.S. (They are right, it's happening.) But how do you know if you've already had it? "The good news is that most vaccinated infections are mild, with symptoms lasting on average for a shorter time overall than Delta and with less severe cases," says Professor Tim Spector. "It's clear that COVID-19 and its new variants will continue to have an impact on our day-to-day lives for some time. It's crucial that we're responsible with our new freedoms and help to keep case numbers down and prevent the virus reaching the more vulnerable groups." Here is the one sure sign you've already had BA.2. Read on—and to ensure your health and the health of others, don't miss these Sure Signs You've Already Had COVID.
Is It BA.2 Or Allergies?

Unless you're tested, it can be difficult to know for sure if your symptoms are BA.2 or seasonal allergies. "We get that question quite frequently—'Are these symptoms allergies or are they COVID?'" says Dr. Shyam Joshi, medical director of allergy and immunology at Oregon Health & Science University. "Sometimes it's hard to tell but generally if we're seeing a lot more itchy watery eyes, sneezing, itchy nose, we're thinking most likely it's going to be allergies."
Did You Lose Your Sense of Taste and Smell?

"One symptom of COVID-19 that is not a symptom of the flu is change in or loss of taste or smell," says Dana Neutze, MD, PhD. "In addition, the full list of symptoms of COVID-19 continues to evolve as we learn more about the virus."
If In Doubt… Stay Home

If you think you might have BA.2, don't take any chances, experts warn. "As our latest data shows, Omicron symptoms are predominantly cold symptoms, runny nose, headache, sore throat and sneezing, so people should stay at home as it might well be Covid," says Professor Spector. "Hopefully people now recognise the cold-like symptoms which appear to be the predominant feature of omicron."
Did You Have a Fever?

One consistent symptom of BA.2 is a fever, so if you didn't experience that, it was most probably allergies. "Take your temperature. That's probably a good first step, since coronavirus almost always includes a fever," says allergist Anu Kewalramani, MD., assistant professor of pediatrics at the University of Maryland School of Medicine. "If your temperature is normal, it is likely allergies. Also, think about whether this happens to you every year. Come March and April, do you usually have itchy eyes and a runny nose?"
The #1 Sure Sign of BA.2 Is a "Bad Cold"

Did you have a cold recently? BA.2 is highly transmissible and has symptoms that closely mirror cold and flu characteristics (runny nose, cough, fatigue), so it's entirely possible you had BA.2 and didn't realize it. "Distinguishing COVID from flu can be difficult because the symptoms overlap so much," explains Dr. Brooke Bozick, an NIH expert on respiratory diseases that affect the lungs.
How to Stay Safe Out There

Follow the public health fundamentals and help end this pandemic, no matter where you live—get vaccinated or boosted ASAP; if you live in an area with low vaccination rates, wear an N95 face mask, don't travel, social distance, avoid large crowds, don't go indoors with people you're not sheltering with (especially in bars), practice good hand hygiene, and to protect your life and the lives of others, don't visit any of these 35 Places You're Most Likely to Catch COVID.