"We have seen a number of individuals, kids more as they go back to school, that they're coming in with a runny nose, sneezing, and slight cough," said pediatric infectious disease specialist Dr. Daisy Dodd with Kaiser Permanente.
Most COVID-19 tests turn out to be negative. Dodd explained it's difficult for parents to tell the difference between the cold, flu and coronavirus. The first piece of advice is to simply be patient.
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"That first day or two, if you have the capacity to stay at home, do so," she said.
COVID tests can't detect the virus until it replicates for about three days, so wait to get tested and call your doctor instead.
How do you know if it's a cold, COVID or the flu?
Dodd said she knows it's the common cold when her patients tell her, "I don't feel good, doctor, but I still can go to school, and I still can go to work."
Common cold symptoms include a mild temperature of 99 degrees, a sore throat, runny nose, cough and thick mucus that changes color. People with flu tend to have a high fever of 101 or 102 degrees, severe sore throat, fatigue, runny nose, dry cough, headache and body aches.
"The flu really knocks you down in bed. Even though you think you are a Superman, you can't get up," she said.
COVID symptoms are similar to flu. A high fever, sore throat, fatigue, headache and body aches, but you can also have shortness of breath, immediate loss of smell and taste and diarrhea.
"When we're talking about COVID, we have to distinguish between the immunized individual and the non-immunized," Dodd said.
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For most people who are vaccinated against COVID, Dodd said a breakthrough infection will likely feel like a common cold.
"A little bit of a runny nose. A little bit of, you know, 'I don't feel good.' You can handle the pain and go on with your day. You might not even realize because your symptoms might be so mild. You may be totally asymptomatic."
Also, allergies can make you feel run down, but Dodd said your mucus will usually run clear. The best advice is to get plenty of rest, eat nutritious meals and wear a mask.