Deaths due to pneumonia were very common a few decades back. Advancement of science and technology has helped to find out effective medicines for the disease. Though treatable, it is still considered as a potentially dangerous condition, as it causes the death of around 60,000 people every year. Causes The most common and serious cause of the disease is bacterial infection, although fungi and viruses can also cause it. In adults, it is mostly caused by the bacterium Streptococcus pneumoniae, while in children of 2-3 years of age, it is usually caused by Mycoplasma pneumoniae. The infection can be acquired at schools, hospitals, or offices by inhaling foreign matter. Breathing certain chemical fumes or gases can lead to lung inflammation. People with weak immune system (for example, people with heart and lung disease, those undergoing chemotherapy, those diagnosed with AIDS) usually catch infections easily. Elderly people, cigarette smokers, and alcoholics are more susceptible to bacterial lung infection. Signs and Symptoms

• Chest pain
• Sweating
• High fever
• Shaking chills
• Shortness of Breath
• Cough with thick, yellow, or greenish sputum
• Fatigue
• Headache, Muscle pain

Contagious Properties Pneumonia itself is not a contagious disease. You won't have the disease just because you spent some time with a person who has it. It is actually hard to catch, it cannot spread from person to person, easily. Exposure is not the only factor that is responsible for development of the disease. People when exposed to bacterial or viral infection, generally exhibit the symptoms of cough and cold. Whether the microorganism will cause pneumonia or not depends on the state of that individual's lungs and overall health. It will depend upon the susceptibility and immunity of that individual. A strong immune system is capable of killing the bacteria. It does not allow them to cause an infection. Moreover, the bacteria are transmitted through infectious secretions. With proper care and cleanliness the transmission can be prevented. When is Pneumonia Contagious Pneumonia due to fungus, toxins, smoke, and chemicals is not contagious. It is contagious when it is caused by bacteria and viruses. The condition is said to be contagious for 48 hours, or for 2-3 days after starting antibiotics. However, if the antibiotics are taken immediately on the onset of the symptoms, then the contagious period reduces. The patient is usually administered a certain dosage of antibiotics to cure the problem. If he suddenly stops taking the medicines, or if he does not religiously follow the instructions of the doctor regarding the intake of antibiotics, then there can still be some microorganisms present in his respiratory track. While sneezing or coughing, he can throw out some of them into the surrounding atmosphere. Thus the person sitting next to him might catch the infection. It is generally assumed that the infection is contagious for anything between 10-14 days after stopping the dosage of antibiotics. Babies generally suffer from a mild form of the infection, called "walking pneumonia" which is contagious. Babies can "walk around" with the disease. Babies if catch the infection from a person, may develop cold and fever, but not pneumonia itself, and such babies would not be as sick as the affected person. Sometimes the symptoms are overlooked considering them as symptoms of common cold and flu. It is necessary to take antibiotics as early as possible, and this usually does not happen because of a long incubation period. Many people do not realize that they have the infection. If you notice flu-like symptoms which do not disappear within a week, consult your physician. Always cover your mouth when coughing or sneezing, and it is better to avoid long-term exposure in crowded areas. Avoid contact with a patient unless he is on antibiotics. The most important thing is that you should always wash your hands before eating, drinking, and after the use of the restroom. This way, you can prevent the microorganisms from entering into your body. Following instructions of your doctor regarding medicines is equally important. Disclaimer: This Buzzle article is for informative purposes only, and should not be used as a replacement for expert medical advice.