Following an appearance at a memorial service in New York on the 15th anniversary of the 9/11 attacks, presidential candidate Hillary Clinton made an early and apparently wobbly exit as she was filmed almost fainting making her way into an SUV.
In a statement issued by her physician, Lisa Bardack, and released by her campaign, Clinton's doctor diagnosed the candidate with pneumonia, adding that Clinton was "overheated and dehydrated" during her public appearance.
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Pneumonia is a common lung infection that can cause mild to severe illness in people of all ages, according to the Centers for Disease Control and Prevention (CDC). Pneumonia can infect one or both lungs.
Typically symptoms of pneumonia may include high fever, persistent cough, chills, headaches, chest pain and more. At its most severe, pneumonia symptoms may include extreme fatigue, nausea, vomiting and even coughing up blood.
Because the more mild signs of pneumonia can mimic a cold or flu -- and in fact Clinton had suffered from a "prolonged cold" related to allergies prior to her pneumonia diagnosis, according to her doctor -- the disease can initially go unnoticed. Clinton likely suffered from a classic case of "walking pneumonia," in which an individual is still ill but feels healthy enough to go about a normal routine.
The infection can be caused by viruses, bacteria or fungi. In the United States, influenza and respiratory syncytial virus (RSV) are most often responsible for viral pneumonia, while Streptococcus pneumoniae (pneumococcus) is a common cause of bacterial pneumonia, the CDC notes. Pneumonia can also be induced by inhaling a liquid or chemical.
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Treatment for pneumonia generally includes bed rest and medications, typically antibiotics or antivirals depending on the cause of the disease. Even with treatment, some symptoms, such as fatigue, can last for a month or more.
Bacterial pneumonia is easier to recover from, with patients typically improving one to three days after antiobotic treatment, according to the National Institutes of Health (NIH). Viral pneumonia sticks around a little longer, however, with symptoms persisting for one to three weeks even with proper treatment.
Pneumonia is preventable, and there are vaccines that hold off infection by some bacteria and viruses that cause the disease.
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