RELATED: If You Got Pfizer, This Is When You’re More Likely to Get Breakthrough COVID. Tiffany Mattingly, RN, the vice president of clinical strategies at The Health Collaborative in Cincinnati, Ohio, told ABC-affiliate WCPO that many people are mistaking their coronavirus symptoms for non-urgent health issues because symptoms of the Delta variant vary from other strains. “Many people think they have sinus infections, that it’s allergy season, that it’s ragweed time, and it’s not. It’s COVID,” Mattingly said. A sore throat is a common sign of a sinus infection and allergies, but doctors say you should now get tested for COVID if you have this symptom or think you have a sinus infection. According to Mattingly, a major problem with breakthrough infections is that these symptoms are typically much less severe in vaccinated individuals, which means they may be even more likely to wait to get tested. “By the time that it gets severe enough that someone decides to go get a COVID test, they may have spread it to multiple people, because a couple of days have passed,” she warns. According to the Centers for Disease Control and Prevention (CDC), fully vaccinated people can still spread the virus if they have been infected with the Delta variant, though they are likely to be infectious for a shorter period of time than unvaccinated people. “Previous variants typically produced less virus in the body of infected fully vaccinated people (breakthrough infections) than in unvaccinated people. In contrast, the Delta variant seems to produce the same high amount of virus in both unvaccinated and fully vaccinated people,” the CDC says. RELATED: For more up-to-date information, sign up for our daily newsletter. In June, researchers from the U.K. released findings from their ongoing ZOE COVID Study, pinpointing what symptoms are more likely from the new, fast-spreading strain of the virus. Sore throat was one of the five most common symptoms among COVID cases in those fully vaccinated. The other common breakthrough infection symptoms now include headache, runny nose, sneezing, and loss of smell. But sore throat is also now one of the five most frequently reported virus symptoms for those unvaccinated as well. According to the researchers, this shows some clear “changes from when COVID-19 first appeared over a year ago.” The other common symptoms for unvaccinated people during the Delta surge include headache, runny nose, fever, and persistent cough.ae0fcc31ae342fd3a1346ebb1f342fcb “A majority of these [Delta] cases start with sniffles, sore throat,” Gabe Kelen, MD, the director of emergency medicine at Johns Hopkins told WMAR, an ABC-affiliate in Baltimore, Maryland. “If you have symptoms, do not assume that this is a summer cold. Even if your symptoms aren’t very strong, what you want to do is make sure you are not spreading COVID to somebody else who is going to have a very bad outcome.” RELATED: This Type of Mask Won’t Protect You From COVID Right Now, New Study Says.