Colds and flu are both highly contagious and have many symptoms in common, but the flu is a serious illness that may have life-threatening complications. In general, a person with the flu will have fever that’s usually between 102ºF and 104ºF. The fever can last 3-4 days. Flu symptoms come on suddenly and may be severe. You’ll experience muscle aches and feel very tired and weak. Some people feel extremely exhausted. Another symptom is a cough that can be severe. Unlike a cold, symptoms like runny nose, sneezing and sore throat aren’t as common with the flu.
The flu may be far more dangerous than a cold and may lead to pneumonia. Both are caused by viruses, but not the same ones.
Cold symptoms appear within one to three days of being exposed to the cold virus. Flu symptoms come on abruptly and may be quite severe including high fever, cough, headache, and muscle and body aches. Gastro-intestinal symptoms such as nausea, vomiting and diarrhea are more common in children than adults.
What if you get the flu?
If you do get the flu, the best advice is to get plenty of rest, drink lots of liquid and avoid using alcohol and tobacco. You can take over-the-counter medicines to relieve symptoms of the flu.
CAUTION: Do NOT give aspirin to children or teenagers who have flu-like symptoms, especially a fever. In some cases, this has caused a serious complication known as Reye’s syndrome.
Some people are more at risk of developing complications of the flu. These include young children and people older than 50. Other at-risk groups include:
- Residents of nursing homes or chronic care facilities
- People with chronic disorders such as diabetes, heart, lung or kidney disorders
- People with a weakened immune system including those with HIV, leukemia or taking medications following an organ transplant
- Women who are pregnant and in their second or third trimester
- People who work in a healthcare facility
If you fall into one of these groups and develop symptoms of the flu, call your doctor immediately.
If you develop complications including trouble breathing, a very high fever, a severe sore throat, a cough that produces a lot of green or yellow mucus, or you feel faint, call your doctor.
There are some medications that may help shorten the flu’s duration and intensity. These include neuramidase, rimantadine and amantadine. Some of these medications only work with certain types of influenza viruses. To be effective, these need to be taken no later than 24 to 48 hours after you first develop symptoms.