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Flu in Adults

Flu in Adults Facts

Influenza (flu) is an acute viral infection of the nose, throat, and lungs. It is a common cause of acute respiratory illness and can affect people of all ages. It occurs every year beginning in late fall, with the peak season for the flu in the northern hemisphere extending from November through March. It infects in a widespread fashion, affecting people of different ages at the same time.

  • Some also confuse influenza with the term stomach flu. However, the latter is an illness associated with nausea, vomiting, and diarrhea and can be caused by bacteria and viruses but not the influenza viruses. It is a stomach illness, whereas the flu is an illness of the respiratory system.
Medically Reviewed by a Doctor on 11/30/2015
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Flu Vaccine Side Effects

In general, all medications, including intramuscular, intradermal, and nasal-spray vaccines, have side effects and the potential for allergic reactions. For most medicines and vaccines, the side effects or reactions are infrequent and are minimal if they do occur. Consequently, the pros far outweigh the cons for vaccination.

Read What Your Physician is Reading on Medscape

Influenza »

Influenza virus infection, one of the most common infectious diseases, is a highly contagious airborne disease that causes an acute febrile illness and results in variable degrees of systemic symptoms, ranging from mild fatigue to respiratory failure and death.

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