"I don't feel good!" Whether you are an adult or a child, there are times when you just want to scream that. When you have a cold or the flu, it is one of those times.
Colds and influenza are caused by different viruses. They share many of the same symptoms and they both make you feel lousy. They are different illnesses and that difference is important.
COLDS
Colds are caused by one of the many, many viruses. You can catch a cold several times a year, and while there are more colds in the winter, you can experience this illness in the summer, too.
A cold is an upper respiratory infection, in the nose and throat. Adults average 2-4 colds per year and children experience 6-8 colds per year. They are contagious and symptoms appear about three days after infection.
Your cold comes with some unpleasant symptoms, runny nose, chest congestion, scratchy throat, sneezing and cough. Adults normally will not have a fever though children might. People with lung problems, smokers, those with COPD or asthma will have more severe symptoms.
A typical cold will last anywhere from a few days to a week. Because it is caused by a virus, there is no cure. Due to the large numbers of viruses, there are also no vaccines.
FLU
Influenza, the flu, is also caused by a virus. There are several types that can cause the flu but normally only two or three types circulate widely during flu season. In temperate climates like the United States, influenza is usually seen from November through March the following year, a seasonal outbreak. In the tropics, influenza may be seen year round.
Influenza is a respiratory infection but it may infect the entire body. Because fewer types of influenza virus circulate, and many are interrelated, if you have the flu you will most likely not catch it again that year. Flu is also highly contagious.
In most people, influenza will begin like a cold. Then you will get worse. And worse. Along with the symptoms of a cold, there will likely be a high fever (over 101 degrees F), very achy muscles and extreme tiredness. Few adults will experience vomiting or diarrhea but children may.
There is no such thing as "the stomach flu". That illness is usually due to a norovirus or to food poisoning.
Just as with a cold, people with lung issues will be sicker. In addition, influenza will have a greater effect on those with immune system issues, the young, the elderly, and those with chronic conditions such as diabetes or heart problems.
Influenza may last longer than a week. There is no cure. There are a number of anti-viral medicines which can be used to reduce the length of the illness. There is also a yearly vaccine, designed to immunize against the expected variants of the flu virus anticipated for that year.
Some people may notice little or no difference between the flu and a cold. Most people who experience both will clearly feel the difference. Whichever illness you have, you will still feel lousy.