(HealthDay News) -- About 10 percent of Americans get the flu each year, mostly as the weather turns colder.
While for most people the flu is a major inconvenience but a minor health threat, for older adults and others with weaker immune systems, the flu can be life-threatening.
The U.S. National Institute on Aging says you should contact a doctor without delay if:
- Your fever goes away and comes back. This could be a sign of a more dangerous infection.
- You start having breathing problems or other serious health issues.
- You don't feel like you're getting better.
- You have a cough that stems from thick mucus.