The flu is a contagious respiratory illness caused by the influenza virus, and its symptoms can range from mild to severe. The following are common signs of the flu:

• Fever or feeling feverish/chills
• Cough
• Sore throat
• Runny or stuffy nose
• Muscle or body aches
• Headaches
• Fatigue (tiredness)
• Some people may have vomiting and diarrhea, though this is more common in children than adults.

Its important to note that not everyone with the flu will have a fever. Flu symptoms often appear suddenly, and people who are sick with the flu may feel weak and miserable. In addition, flu symptoms are similar to those caused by COVID-19, so testing is necessary to know whether you have the flu or COVID-19.

People experiencing emergency symptoms of the flu, such as difficulty breathing or shortness of breath, chest pain, ongoing dizziness, seizures, worsening of existing medical conditions, or severe weakness or muscle pain, should obtain medical care right away. Children and adults at high risk may develop complications that may include pneumonia, bronchitis, asthma flare-ups, heart problems, sinus problems, and ear infections.