What is Pneumonia?
Pneumonia is an inflammation of the lungs caused by infection. Bacteria, viruses, fungi or parasites can cause pneumonia. Pneumonia is a particular concern if you are older than 65 or have a chronic illness or weak immune system. It can also occur in young, healthy people. Pneumonia can range in seriousness from mild to life-threatening. Pneumonia often is a complication of another condition, such as the flu. Antibiotics can treat most common forms of bacterial pneumonias, but antibiotic-resistant strains are a growing problem. The best approach is to try to prevent infection.


Pneumonia often mimics the flu, beginning with a cough and a fever, so you may not realize you have a more serious condition. Symptoms can vary depending on your age and general health. The signs and symptoms of pneumonia may include:

2)Lower-than-normal body temperature in older people
4)Shortness of breath
6)Shaking chills
7)Chest pain that fluctuates with breathing (pleurisy)
9)Muscle pain


Pneumonia has many possible causes, but the most common ones are bacteria and viruses normally encountered in the environment. Usually your body keeps these microbes from invading your lungs. Sometimes, though, a robust germ can breach your defenses, regardless of your general health.

The germs that cause pneumonia in otherwise healthy people are not usually the same ones that cause pneumonia in hospitals and other health care settings. Similarly, the germs that can infect your lungs if you inhale foreign substances (inhalation or aspiration pneumonia) differ from those that cause more-common types of pneumonia. The same is true of the germs that cause pneumonia in people with weak immune responses.

Community-acquired pneumonia

When you get pneumonia from contact with germs you encounter in the course of your normal routine, it is called community-acquired pneumonia. These commonplace germs generally cause mild forms of pneumonia that doctors can treat without difficulty. The microbes responsible for most community-acquired pneumonia are:

1)Bacteria. The bacterium that causes most cases of community-acquired pneumonia is Streptococcus pneumoniae. Other possible agents include Staphylococcus aureus, Haemophilus influenzae and Klebsiella pneumoniae. It is not unusual to have pneumonia caused by more than one type of bacteria at a time. Methicillin-resistant Staphylococcus aureus (MRSA), an antibiotic-resistant bacterium once found only in health care settings, now causes skin infections and pneumonia in the community, too.

2)Bacteria-like organisms. Mycoplasma pneumoniae is a tiny organism that typically produces milder signs and symptoms than other types of pneumonia. Walking pneumonia, a term used to describe pneumonia that is not severe enough to require bed rest, may result from Mycoplasma pneumoniae. Legionella and Chlamydia pneumonia are two other pneumonia-causing germs that are neither bacteria nor viruses.

3)Viruses. Some of the same types of viruses that cause the flu and colds can also cause pneumonia. Although most cases of viral pneumonia are mild and resolve in time with rest and fluids, viral pneumonia caused by influenza viruses can become very serious. Viral pneumonia can set up a prime environment for the invasion of bacteria, causing a second infection.

4)Fungi and parasites. Other less-common causes of community-acquired pneumonia include fungi, parasites and the germ that causes tuberculosis. Most cases of parasitic pneumonia occur in people who live or have traveled in developing countries.

5)Health-care-acquired pneumonia. Severe, difficult-to-treat bacterial pneumonia is a major problem in health care facilities -- not only hospitals and nursing homes, but also kidney dialysis centers and outpatient infusion centers, where people regularly receive cancer chemotherapy and other intravenous medications.

Health-care-acquired pneumonia is sometimes caused by strains of Streptococcus pneumoniae and Haemophilus influenzae, which also occur in the community. But the list of germs causing hospital-acquired pneumonia does not stop there. In the hospital setting, bacteria may quickly become resistant to standard antibiotics, so drug resistant germs are much more common. Resistant bacteria such as Pseudomonas aeruginosa and MRSA make treatment difficult. People on breathing machines (ventilators), often used in hospital intensive care units, are particularly vulnerable.

With so many possible culprits and a high likelihood of resistant strains, the challenge in the hospital is to identify the causative organism and determine what antibiotics will work against it.

6)Inhalation or aspiration pneumonia. Aspiration pneumonia occurs when you breathe foreign matter into your lungs. This can happen if you vomit while asleep or unconscious and breathe in some of the contents of the stomach. Difficulty swallowing, which occurs with diseases such as amyotrophic lateral sclerosis (ALS), Parkinsons disease and strokes, occasionally leads to aspiration pneumonia.

7)Opportunistic viral, bacterial and fungal pneumonias. These types of pneumonia strike people with weakened immune systems. Organisms that are not harmful for healthy people can be dangerous for people who have had an organ transplant and people with AIDS and other conditions that impair the immune system. Medications that suppress your immune system, such as corticosteroids or chemotherapy, also can put you at risk of opportunistic pneumonia.

Western Medicine Treatment

The best approach to treating pneumonia depends on a number of factors, including your age and general health, the organism or organisms involved, and the setting -- community or health care -- where the infection developed.

Treatment may include:

2)Antibiotics are used to treat bacterial pneumonia. Other medications may help improve breathing and relieve symptoms in bacterial and viral pneumonia.

Medication options include:

A)Antibiotics. The decision to treat pneumonia with an antibiotic is not always straightforward. Even with a high likelihood of bacterial infection, it takes time to identify the bacterium involved and choose the best antibiotic to wipe it out. Initially, your doctor may prescribe a particular antibiotic based on trends in infection and antibiotic use in your area. If tests show that you need a different drug or your condition does not improve, you may switch to another antibiotic.

B)Antivirals. Your doctor may recommend antiviral medication for viral pneumonia. Antibiotics are not effective for treating viral pneumonia.

C)Fever reducers. You may treat your fever with aspirin, ibuprofen, naproxen or acetaminophen. (Children should not take aspirin.)

D)Cough medicine. Talk to your doctor before taking cough medicine. Coughing helps loosen and get rid of extra sputum. If your doctor advises cough medicine, only take enough to calm your cough and get some rest.

Hospital admission

Community-acquired pneumonia generally does not require hospital care. You may need to be admitted, however, if you have any two of these indicators of severity. If you have three or more, you may need admission to an intensive care unit:

1)You are older than 65 years
2)You become confused
3)Your breathing is rapid
4)Your blood pressure drops
5)Your need breathing assistance, including oxygen or respiratory therapy

Adpoted From Mayo Clinic