By Heather Brown

MINNEAPOLIS (WCCO) — Hillary Clinton says she’ll be back on the campaign trail by the end of the week.  On Friday, her campaign said she was diagnosed with pneumonia. That had a number of WCCO viewers sending in questions about the disease. So, what is pneumonia?  Good Question.

One hundred years ago, pneumonia and heart disease traded places for the number one cause of death.  Now, the mortality rate is far lower, but 50,000 people in the U.S. still die each year from pneumonia.  That’s just a fraction of the 2 to 5 million Americans the Centers for Disease Control estimates come down with the disease each year.

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“Pneumonia’s an infection that involves the lungs,” says Dr. Mark Sprenkle, chief of pulmonary and critical care at the Hennepin County Medical Center. “It can be caused by many different kinds of organisms from viruses to bacteria to fungus.”

According to the American Lung Association, common symptoms include cough, fever, chills and shortness of breath.  The term “walking pneumonia” is used to describe a less severe kind of pneumonia.

“Sometimes if people would have a very mild case of pneumonia, they might just think they have the flu or a bad cold with a cough,” says Sprenkle.

In combination with a patient’s history, doctors often take a chest X-ray to look for the presence of inflammation in the lungs that would indicate pneumonia.  Generally, they will prescribe antibiotics, even if they don’t know what kind of organism is causing the disease.

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Pneumonia can be contagious and spread from person to person.

“It can be inhaled. Some are caught by droplets from people when they sneeze or cough,” says Sprenkle. “Other times, it’s less clear. Bacteria can colonize the back of the throat and if people aspirate a little bit of that down in to the lungs, that can lead to it too.”

Sometimes, a viral infection, like influenza, can cause problems in the respiratory tract. That could also predispose people to developing more serious bacterial pneumonia.

Sprenkle says there is a vaccine for pneumococcal pneumonia, one specific kind of bacterial pneumonia. But, there are many different kinds of bacteria that can cause pneumonia and most of those don’t have any specific vaccine. Doctors recommend children younger than five and adults over 65 and older get vaccinated against pneumococcal pneumonia.

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With treatment, most people with a mild form of pneumonia recover within one to three weeks.  Those who end up in the hospital are often older, very young or generally have other underlying health conditions.

Heather Brown