Before we learn about the spread of pneumonia, let us first understand what happens when pneumonia strikes and what causes this infection. This ailment can spread through air, water and it can infect you on its own, as there are several infectious microbes of pneumonia on your body right now. You can potentially get invaded the moment your body's immunity and defensive mechanisms drop down. About Pneumonia and its Causes Pneumonia is not a single disease or infection caused by one specified virus or bacteria but rather it can be caused by a lot many different causes such as physical injury, trauma, chemical burns, poison exposure, etc. What exactly happens when a person is affected by pneumonia is that the lungs or a single lung suffers from inflammation, especially of the alveoli. Alveoli are the miniature hollow cavities in the lungs which facilitate the exchange of gases (pure and impure). In some cases lungs also get filled with consolidation and exudation fluids. Common and primary symptoms of pneumonia consist of cough, cold, fever and almost all common flu symptoms. In addition to that chest pain and breathing problems are also involved. Pneumonia is often mistaken for common flu in the first instance. Pneumonia being caused as a result of several different microbes which include, viruses, bacteria, fungi, parasites and also some Idiopathic causes, the rate of contagious is pretty high and the infection can travel very rapidly. One of the elementary and also probably the best way to keep the contagious behavior of pneumonia under check is basic hygiene and community cleanliness. The encroachment of microbes into the body starts the infection. Normally the infectious microbes are held off by the natural defenses of the body. However, a weakened body, direct and unavoidable intake of such infected air or handling of contaminated objects sets off the contagious disease. Invading microbes settle into the entire respiratory system starting from then nose to the lungs and the alveoli. White blood cells trigger the defensive mechanism of the body, by resorting to inflammation of lungs and secretion of fluids and ejection of pus in an attempt to throw out the infection. Now commonly this situation seldom arises, owing to the fact that microorganisms are warded off by the respiratory system right in the beginning of the tract, however once invaded, the respiratory system becomes weak and things can go from bad to worse. Is Pneumonia Contagious in Adults? Pneumonia is indeed contagious in adults, and simple things such as not covering your mouth while sneezing or coughing are sufficient to contribute to its spread. The problem with pneumonia causing microbes is that they attack an invade anything and everything. Causes such as smoking, common cold and general illnesses often tend to work in conjugation with the pneumonia causing viruses. Other way round, pneumonia follows such minor ailments, and as the immune system is weak the body is not able to suppress pneumonia causing viruses. There are several ways in which pneumonia and its causes are classified. Community-acquired pneumonia is the most common and also the most contagious pneumonia class. Community-acquired pneumonia is usually spread as a result of existence of the microbes in the environment, plus company of any person infected with this disease often tends to lead to pneumonia. Adults especially are a bit luckier than kids and old people as their stronger immune system tends to get rid of several types of microbes. Here some pneumonia causing microbes that may prove to be contagious in adults. Pneumonia Causing Microbes

Viruses	Parasites	Bacteria	Fungi
Influenza, parainfluenza, respiratory syncytial virus, metapneumovirus and adenovirus are the viruses that cause pneumonia if they invade the respiratory tract. Chickenpox, Severe acute respiratory syndrome, avian flu, and hantavirus are the viruses which often act in conjugation with other microbes to cause pneumonia.	There are several bacteria which independently or in collaboration with other microbes can potentially cause pneumonia. Atypical organisms (Chlamydophila pneumoniae, Legionella pneumophila, Mycoplasma pneumoniae), Streptococcus pneumoniae (Streptococcus pneumoniae), Haemophilus influenzae, Enteric Gram-negative bacteria (Escherichia coli, Klebsiella pneumoniae) and Pseudomonas aeruginosa are the common invaders.	Some specified fungi such as cause pneumonia include, histoplasmosis, coccidioidomycosis and pneumocystis pneumonia. Some fungi such as pneumocystis pneumonia and sporotrichosis act in conjugation with some other ailments. Cryptococcosis, a type of fungus, on the other hand infects through the intake of yeast.	Invasion of parasites usually occurs when the immune system, white blood cells, and in general the body has been weakened. Ascariasis, Schistosoma, Toxoplasma gondii are the three prominent parasitic pneumonia causing microbes.

These invasive microbes can spread very quickly through several mediums such as air, water, droplets of sneezed secretion and saliva, even a simple hug or a touch can potentially spread the microbes. A person becomes susceptible, especially when his immune system has been weakened. A person already suffering from another ailment should be extra cautious. In such a case, pregnant women need to be extra cautious as they too are susceptible to microbes and other related ailments. The only bold strong measure against such an infection is of course, vaccination and properly building up the immunity of the body. Last but not the least, it is of crucial importance that when you start experiencing advanced symptoms that upgrade from common flu, it's time to rush to the doctor. In case if you experience any of the following symptoms for a prolonged time period, chronically, it's time to rush to the doctor:

• Chest pains
• Prolonged fever
• Breathing problems
• Chills and sweating
• High fever
• Fatigue along with muscle pain

Please make sure that you get to your doctor as soon as possible as more you wait, the weaker the immunity and worse the situation may get. There are cases where the microbes are hospital acquired, that is if you are admitted in the hospital. However, the doctors and medical staff often take the best possible precautions in cases where even the slightest symptoms show up. Depending upon the level and severity of the infection, antibiotics and vaccines that act against the said microbes are utilized. As this ailment is caused by a variety of microbes treatment differs from case to case, and often combinations of medication are used for eradication. On the whole, personal and community hygiene and vaccinations are the best options to prevent the spread of pneumonia.