Pneumonia is a lung infection resulting from breathing germs into the lungs, and it can cause cough, fever, shortness of breath, chest pain and nausea, explains WebMD. Antibiotics are the most common treatment for pneumonia, and most individuals see improvement in symptoms after two or three days.
Pneumonia can be the result of any number of circumstances, including infections from bacteria, viruses, fungus or even parasites, notes WebMD. Most commonly, though, an infection by the bacteria Streptococcus pneumoniae causes the illness. Individuals often contract the infection by breathing in infected particles or bacteria, and it is more likely to affect an immune system compromised by a cold or the flu, as well as by conditions such as AIDS.
The symptoms of bacterial and nonbacterial pneumonia are usually fairly similar, according to WebMD. However, the symptoms of bacterial pneumonia are sudden, compared to nonbacterial pneumonia, when the symptoms arrive more gradually and usually more mildly.
When the prescribed antibiotics do not effectively treat the infection, a culture and sensitivity test may be necessary to determine the specific cause of the infection; for example, the bacteria may be resistant to the antibody. However, unless the symptoms are severe or accompany other health problems, individuals usually do not require hospitalization, reports WebMD.