(WGN Radio) – With every new season comes a new variant of COVID – or so it seems. Over the past several weeks, KP.3.1.1, which is one of the FLiRT subvariants of the virus, has become more common. It now makes up a majority of COVID-19 cases, the Centers for Disease Control and Prevention estimates. Have the changing variants brought changing symptoms associated with COVID-19? The fundamentals haven't changed, experts say, as the virus still causes respiratory illness. However, that can make things confusing heading into fall and winter, when flu and RSV are likely to spike too. "While it is a different variant, it's starting to look a lot more like the flu-like symptoms: the cough, the sore throat, the runny nose, the sneezing and the muscle aches," said Dr. Jim Adams, chief medical officer of Northwestern Medicine, in an interview with WGN Radio. "So it's harder to differentiate." One set of symptoms people are paying more attention to lately is the gut. "Personally, I've seen a lot of people this summer with COVID with a lot of GI (symptoms) – stomach pains, diarrhea – but we've known that's always been possible," Adams said. Even though stomach issues aren't what we talk about most in terms of COVID symptoms, they affect about half of people infected with the virus, according to the University of Nebraska Medical Center. How COVID-19 impacts people varies from person to person. While some may lose their sense of smell or be bedridden, some may hardly feel anything or confuse it with the common cold. "It's hard to differentiate COVID vs. non-COVID based on symptoms now," Adams said. Taking a COVID test when you feel sick can help you get answers – and better treatment, if necessary. Listen to more of the interview with Dr. Adams in the audio player below: COVID-related hospitalizations finally appear to be dipping after the prolonged summer spike, but it's not yet clear what will happen with the virus' spread as we head into fall and the holiday season. "We don't know what (COVID) going to do in the fall," said Adams. "Every year is different." Flu and COVID booster shots, updated to target this year's variants, are available at pharmacies and doctors' offices. The CDC recommends everyone 6 months and older receive both. Latest News Can the woolly bear caterpillar really predict winter weather? Former Boar's Head sanitation manager recounts where Virginia plant went wrong Live music series coming to Scotlandville Plaza: What to know about dates, music artists Best Japanese Cars for 2024 Why an Alaska island is using peanut butter and black lights to find a rat that might not exist