There are about 30 different causes of pneumonia. However, they all fall into one of these categories:
Infective pneumonia: Inflammation and infection of the lungs and bronchial tubes that occurs when a bacteria (bacterial pneumonia) or virus (viral pneumonia) gets into the lungs and starts to reproduce.
Aspiration pneumonia: An inflammation of the lungs and bronchial tubes caused by inhaling vomit, mucous, or other bodily fluids. Aspiration pneumonia can also be caused by inhaling certain chemicals.
Bacterial pneumonia can attack anyone. The most common cause of bacterial pneumonia in adults is a bacteria called Streptococcus pneumoniae or Pneumococcus. Pneumococcal pneumonia occurs only in the lobar form.
An increasing number of viruses are being identified as the cause of respiratory infection. Half of all pneumonias are believed to be of viral origin. Most viral pneumonias are patchy and the body usually fights them off without help from medications or other treatments.
Pneumococcus can affect more than the lungs. The bacteria can also cause serious infections of the covering of the brain (meningitis), the bloodstream, and other parts of the body.
Nice To Know:
The viruses and bacteria that cause pneumonia are contagious and are usually found in fluid from the mouth or nose of an infected person. Pneumonia can spread by coughs and sneezes, by sharing drinking glasses and eating utensils with an infected person, and contact with used tissues or handkerchiefs.
Handwashing is important when around a person with pneumonia, since the bacteria and viruses can also be spread to your hands and then to your mouth.
Inhaling vomit, irritating fumes, or other substances can result in aspiration pneumonia. Agents such as petroleum solvents, dry cleaning fluid, lighter fluid, kerosene, gasoline, and liquid polishes and waxes are the most likely causes. Pulmonary edema, or fluids in the lung from injury, can develop rapidly. With repeated exposure, the lungs may lose elasticity and small airways may become obstructed. This can lead to increased reactive airway disease and chronic lung disease in adults.
Nice To Know:
Although most cases of pneumonia are caused by a viral or bacterial infection, the disease can also be caused anything that obstructs the bronchial tubes. Tumors, peanuts, hard candies, or small toys in the bronchial tubes can trap bacteria, viruses, or fungi, resulting in pneumonia.