Medical Author: Melissa Conrad Stöppler, MD
Other symptoms can occur, like
- nausea and vomiting,
- muscle or body aches,
- tiredness and fatigue,
- appetite loss,
- sore throat, and
Other conditions can sometimes cause similar symptoms, leading people to wonder if they really have the flu or a different condition. Haemophilus influenzae is a bacterium that was incorrectly considered to cause the flu until a virus was demonstrated to be the correct cause in 1933. This bacterium can cause lung infections in infants and children and can sometimes cause sinus or other infections. Other bacterial or viral infections, including the common cold, may cause symptoms similar to the flu. Sometimes with a runny nose, sneezing, head congestion, chest discomfort, stuffy nose, and cough, it is hard to determine whether a cold or the flu is the cause of the symptoms, although the flu tends to produce higher fever than the common cold. Sometimes, allergies produce severe respiratory symptoms as well. Symptoms of certain complications of the flu, such as pneumonia, lead to similar symptoms.
Causes of the flu (influenza)
Influenza viruses cause the flu (influenza). Influenza viruses are divided into three types, designated influenza types A, B, and C. Influenza types A and B are responsible for epidemics of illness that occur almost every winter and are often associated with increased rates of hospitalization and death. Influenza type C usually causes either a very mild respiratory illness or no symptoms at all.
Nguyen, Hien H. "Influenza." Medscape. Nov. 22, 2016. <http://emedicine.medscape.com/article/219557-overview>.
Pictures, Images, Illustrations & Quizzes
10 Facts About Flu Shots
Watch this pictures slideshow for more information about flu shots. Get the facts on different types of influenza vaccines and...
10 Foods to Eat When You Have the Flu in Pictures
If you're sick with the flu, you'll want to know the best foods to make you feel better. Learn some of the soothing, nutritious...
A Cold or The Flu? How to Tell the Difference
Learn common symptoms of a cold and the flu. Discover the difference between a cold and the flu. Read about cold and flu...
Cold & Flu Quiz: Influenza vs. Common Cold
Aches? Pain? Fever? This Cold & Flu Quiz tests your knowledge on the difference between coming down with the common cold and...
Cold, Fever and Flu Treatment in Children: Medications and Home Remedies
Colds and fevers are some of the most common ailments in children. Learn common cold symptoms, treatment options, over the...
Home Remedies for the Flu or a Cold
Watch this pictures slideshow and learn about home remedies for sick children. Get tips on how to treat a sore throat, cough,...
Natural Remedies for Cold and Flu
What natural remedies work for the flu and common cold? Many claim cold symptoms and flu symptoms can be relieved with Echinacea,...
Picture of Influenza Virus
The flu is caused by viruses that infect the respiratory tract which are divided into three types, designated A, B, and C. See a...
Tips to Calm Your Cough in Pictures
Sick at home? Need relief from a nagging cough? See which home remedies and other treatments help relieve coughing and when it's...
Other Causes of Flu
Subscribe to MedicineNet's General Health Newsletter