Influenza, or “flu,” is a contagious respiratory virus. Flu season usually begins in the fall and can continue through late spring.
Anyone can be infected by the flu virus. Flu can be mild or serious for some and deadly for others. Flu causes hospitalizations and deaths, especially among vulnerable groups such as the very young, people ages 65 and older, and those with chronic medical conditions.
How flu is spread
The flu can spread quickly from person to person. When a person with the flu sneezes, coughs, talks, or laughs, the flu virus can spread into the air as droplets from the mouth or nose. These droplets can spread to people and surfaces within 3 to 6 feet.
The flu virus can spread to your hands if you touch anything that has the virus on it. If you then touch your eyes, nose, or mouth, you can get the flu.
You may be able to spread the flu virus to others 1 day before you feel sick and up to 5 days after getting sick.
Who is most at risk for severe infection?
If you’re in a high-risk group, you can become extremely ill from the flu. Be sure to take special precaution to prevent the flu if you have any of the following conditions:
- Chronic bronchitis
- Heart disease
- Kidney disease
- Lung disease
- Weakened immune systems
Symptoms of flu
The symptoms of flu are:
- Fever (usually high)
- Body aches
- Chest discomfort
- Runny or stuffy nose
- Sore throat
Severity of Symptoms
Both the seasonal flu and H1N1 flu can vary in severity from mild to severe. While some persons experience mild symptoms, not much different than a cold, others may get a severe infection that requires hospitalization. Some cases could even result in placement in an intensive care unit or death.
Know when to seek medical care for flu.
Is it a cold... or the flu?
Although some of symptoms of seasonal flu are the same as a cold, people with colds don’t usually have fevers over 100.5°F, chills, muscle aches or body pains—all of which are common with the flu.
VA has tools to help you better understand the differences between colds and flu and know when to seek medical care.
- Take VA's easy and useful flu self assessment.
- Download a flu self assessment flowchart (560 KB, PDF).
Note: These tools are intended for Veterans and their caregivers. They are provided for information purposes only. They should not be used as a substitute for evaluation and treatment by a healthcare professional. Your privacy is protected: The self assessment tool does not capture identifiable information in any manner.
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