The flu is a common yet serious viral infection caused by the influenza virus. It spreads quickly and easily from person to person, making you sick for days or weeks. Flu symptoms range from mild to severe and can worsen if left untreated — especially in vulnerable populations like older people, children and immunocompromised individuals.
Knowing what you're up against is essential to protecting yourself and your loved ones from the flu.
Common Flu Symptoms
The most common flu symptoms include:
- Aching muscles: Abnormal muscle soreness
- Chills: Sudden cold sensations running through your body
- Congestion: Buildup of mucus in the nose, throat and sinus cavities
- Cough: Persistent (sometimes hacking) cough that may expel mucus
- Fatigue: Feeling tired and generally unwell
- Fever: Elevated body temperature
- Headaches: Mild to severe throbbing head pain
- Sore throat: Severe pain in the back of the mouth and esophagus
These symptoms usually appear between one and four days after exposure to the flu virus.
Millions of people get sick with the flu every year. While it’s one of the most infectious diseases in the world, less than half of the adult U.S. population gets their flu shot.
Approximately 30 million cases of the flu are diagnosed each year, though approximately 60% of flu cases can be prevented with a flu shot.
Influenza is most contagious during its first three days of incubation. When left untreated, the flu can develop into bacterial pneumonia, earaches or sinus infections. Influenza can also worsen symptoms of chronic conditions like heart failure, asthma or diabetes.
Flu Recovery Timeline
- Days 1 to 2: Onset of symptoms
- Days 3 to 5: Peak flu symptoms
- Days 5 to 7: Gradual improvement
- Days 7 to 10: Approaching recovery
- Days 10 to 14: Complete recovery
Preventive Measures
The most effective way to prevent catching or spreading the flu is by getting your annual flu shot. Try to get the vaccination early — at least two weeks before the start of flu season in the fall. In addition to getting your annual flu shot, here are some more preventive measures you can take:
- Disinfect surfaces: Use chemical disinfectants to kill bacteria and viruses on common surfaces.
- Hygiene: Follow the proper steps for hand-washing. Wash your hands with soap and water, use hand sanitizer when necessary and cover coughs and sneezes to help prevent the spread of the virus.
- Practice healthy habits: Nutrition, exercise, adequate sleep and minimizing face-touching support your overall immune system.
- Reduce transmission: Avoid close contact with sick individuals and stay home if you’re unwell.
By following these key measures, you’re doing everything you can to prevent the spread of the flu.
