- By Dana Sparks
Infectious Diseases A–Z: The common cold versus the flu
Influenza and the common cold are respiratory illnesses caused by viruses. The more intense flu symptoms tend to come on more abruptly than the gradual, more mild symptoms of a cold. Dr. Nipunie Rajapakse, a pediatric infectious diseases specialist at Mayo Clinic, explains these two viral illnesses.
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“Influenza is a specific type of infection caused by a specific virus. That’s usually influenza A or influenza B virus. The cold, on the other hand, is caused by hundreds of different types of viruses. The main difference is that influenza tends to cause more systemic symptoms. You are more likely to have fever, body aches and pains than you are with the cold, which tends to be usually just runny nose, sore throat and possibly some cough," says Dr. Rajapakse.
Flu symptoms include:
- Fever over 100.4 F
- Aching muscles, especially in your back, arms and legs
- Chills and sweats
- Dry, persistent cough
- Fatigue and weakness
- Nasal congestion
- Sore throat
- Sudden onset of symptoms
“Once you have a viral infection of any kind, there is an increased chance that you might develop a superimposed bacterial infection," says Dr. Rajapakse. "Your risk of developing a bacterial sinusitis could go up, and your risk of developing pneumonia or a lung infection can go up as well."
"If you seem to be recovering from a cold or flu, and then suddenly start having fevers or feeling worse again, you should see your health care provider to determine if you might have developed a bacterial superinfection," says Dr. Rajapakse. "Taking antibiotics, which only work against bacteria and not viruses, during a cold or flu does not prevent you from developing a secondary bacterial infection and can cause serious harm. The antiviral medication oseltamivir (Tamiflu) only works against the influenza virus and not against viruses that cause the common cold. The flu shot provides protection against influenza A and B viruses but not common cold viruses.”
- Runny or stuffy nose
- Sore throat
- Gradual onset of symptoms
Dr. Rajapakse says there is no cure for the common cold, but there are ways to feel better. “The best things that we recommend for people who have the common cold are to get plenty of rest, to drink plenty of fluids, and use symptomatic relief methods in terms of ibuprofen or acetaminophen to help yourself feel better until your body’s able to fight it off itself."
"If you have a cold that has gone on for more than 10 to 14 days, generally that would be an appropriate time to see your health care provider to see if maybe something else is going on, or whether you may have developed some sort of complication," says Dr. Rajapakse.
It is also important to wash your hands well, cover your cough and dispose of used tissues carefully to avoid spreading cold and flu viruses to others.