Pneumonia is an infection that can affect one or even both lungs. It can be caused by fungi, bacteria, or viruses. Pneumonia causes inflammation in the air sacs of the lungs. The alveoli (or air sacs) fill with fluid or pus, making it difficult to breathe. There are symptoms of the disease which can range from mild to life-threatening. The severity of the disease usually depends on factors like the cause of inflammation, type of organism causing the infection, and the age and general health of the person concerned.

Many different kinds of germs infect the lungs and cause pneumonia. Infected lungs leak fluids and shed dead cells. This material clogs up air sacs and makes it hard for the lungs to do their job of getting oxygen into the blood. Complications of pneumonia include sepsis, pleural effusion, and empyema. Influenza and respiratory syncytial virus are the most common viral causes of pneumonia. Antiviral medications may be used to treat pneumonia caused by some types of viruses.

Risk factors for pneumonia include age over 65 or under 2, having certain chronic medical conditions (including underlying lung disease, cigarette smoking, alcoholism, and neurological problems), or sustaining injuries that interfere with swallowing or coughing.

Antibiotics treat pneumonia by controlling the bacterial or fungal infection. The initial choice of antibiotic depends on the organism presumed to be causing the infection as well as local patterns of antibiotic resistance.

Vaccinations are available against several common organisms that are known to cause pneumonia.

Flu and pneumonia pose special problems for heart patients. In fact, influenza can cause complications, including bacterial pneumonia, or the worsening of chronic heart problems.

A yearly flu shot can help guard against the contagious illness, which is caused by influenza viruses. Flu vaccines are created to combat the strains of flu expected to be circulating in a given year.

There are other precautions you can take to avoid the flu. It’s important to stay away from people who are sick. But prevention remains the best bet.