Influenza, or “flu” for short, is an illness caused by the influenza virus. If you have ever had the flu, you know how miserable it can make you feel. The virus attacks your respiratory system and produces many uncomfortable symptoms, which last between one and several days.
The flu is not a serious health problem for most people, but if you are elderly, are very young, are pregnant, or have a compromised immune system, the virus can be deadly if not treated.
Common flu symptoms | Symptoms
Most people who contract the flu virus will experience several symptoms. These include:
- a fever
- aches and pains throughout the body
- a sore throat
- an extreme feeling of fatigue
- a persistent and worsening cough
- a stuffy or runny nose
Not everyone with the flu has every symptom, and the seriousness of the symptoms varies by individual.
Flu and fever
A fever is a common symptom of the flu virus, but not everyone who gets the flu will have one. If you do experience a fever with the flu, it is typically high, over 100ºF (37.78ºC), and is partly responsible for why you feel so bad.
Treat a case of the flu seriously, even if you don’t have a fever. You are still contagious and your illness could progress and become a real concern, even if your temperature is not elevated.
Other causes of fever
There are many other causes of a fever besides the flu virus. Any type of infection, whether bacterial or viral, can cause you to run a fever. Even being sunburned or experiencing heat exhaustion can elevate your temperature. Some types of cancer, certain medications, vaccines, and inflammatory diseases, such as rheumatoid arthritis, may also be accompanied by a fever.
Flu vs. cold
If you have flu-like symptoms but no fever, you might suspect that you have a cold. It is not always easy to tell the difference, and even a cold can cause you to have a mild fever.
In general, all symptoms are worse when you have the flu. You are also more likely to have congestion, a runny nose, a cough, a sore throat, or sneezing with the flu. Exhaustion is also common with the flu. This tiredness is not nearly as extreme when you have a cold.
Treatment for the flu is limited. If you visit your doctor quickly enough, they may be able to give you an antiviral medication that can shorten the duration of the infection. Otherwise, you must simply stay home so that you can rest and recover. It’s also important to stay home and rest so you avoid infecting others. Sleep, drink plenty of fluids, and stay away from others.
Feed a cold, starve a fever
Common wisdom says that you should starve a fever, but the old saying just isn’t true. There is absolutely no benefit to not eating when you are sick, unless the illness is in your digestive tract. In fact, food will help you keep up your strength and give your immune system the energy it needs to fight the virus. Drinking liquids is also very important when you have a fever because you can become dehydrated quickly.
When to worry
For most people the flu is unpleasant but not serious. Anyone at risk for complications, however, should see a doctor if they suspect the flu. These people include:
- the very young
- the elderly
- those with chronic illness
- those with a compromised immune system
Even people who are usually healthy can have a flu that progresses into a worse illness. If you do not feel better after a couple of days, see your doctor.
The nasty virus that attacks your stomach and makes it impossible to keep food down for a day or two is not related to influenza. We often call it the flu, but this stomach bug is really termed viral gastroenteritis. It does not always cause a fever, but a mild increase in your body temperature might occur with this infection.