Symptoms of the flu tend to start quickly and can include fever, chills, dry cough, and sore throat. People often confuse cold symptoms with those of the flu. However, cold symptoms are usually milder and don't last as long as flu symptoms. You can spread the flu to others before your symptoms start and for another 3 to 4 days after your symptoms appear.
Symptoms of the Flu: An Overview
It's easy to confuse a common cold with flu symptoms. However, cold symptoms are usually milder and don't last as long as the flu symptoms. If you become infected with the flu virus, you will usually feel flu symptoms 1 to 4 days later. It is important to note that you can spread the flu to others before your flu symptoms start and for another 3 to 4 days after your flu symptoms appear.
(Click Flu Virus for more information about the flu.)
Common Flu Symptoms
Common flu symptoms start quickly and can include:
Typically, the fever will begin to decline on the second or third day of the illness.
Flu Symptoms and the Stomach Flu
Although nausea, vomiting, and diarrhea can accompany flu symptoms, especially in children, gastrointestinal flu symptoms rarely occur. The illness that people call "stomach flu" is not influenza (the flu).
Complications of the Flu in Adults
Complications of the flu in adults can occur if they develop a bacterial infection, which can cause pneumonia in already weakened lungs. However, the flu virus alone can also cause pneumonia.
Complications of the flu usually appear after the patient starts to feel better. After a brief period of improvement, you may suddenly get symptoms, such as:
- High fever
- Shaking chills
- Chest pain with each breath
- Coughing that produces thick, yellow-green mucus.
Pneumonia can be a serious and sometimes life-threatening condition. If you have any of these symptoms, you should contact your healthcare provider immediately to get the appropriate treatment.