Flu symptoms will often start quickly. You can start to feel sick about 1 to 7 days after you come in contact with the virus. Most of the time symptoms appear within 2-3 days.
The flu spreads easily. It can affect a large group of people in a very short amount of time. For example, students and co-workers get sick within 2 or 3 weeks of the flu's arrival in a school or workplace.
The first symptom is a fever between 102 and 106°F. An adult often has a lower fever than a child.
Other common symptoms include:
- Body aches
- Flushed face
- Lack of energy
- Nausea and vomiting
The fever, aches, and pains begin to go away on days 2 through 4. But new symptoms occur, including:
- Dry cough
- Increased symptoms that affect breathing
- Runny nose (clear and watery)
- Sore throat
Most symptoms go away in 4 to 7 days. The cough and tired feeling may last for weeks. Sometimes, the fever comes back.
Some people may not feel like eating.
The flu can make asthma, breathing problems, and other long-term illnesses and conditions worse.