|MadSci Network: Cell Biology|
Pink eye (also called conjuctivitis) has several possible causes. It can be caused by allergies, chemicals, bacteria, and viruses. Because there are several different causes of pink eye, the length of time of the condition also varies. If the condition is caused by allergies or chemicals, pink eye will last as long as you are in contact with the allergens (like pollen) or chemicals. For someone with allergies, this may mean having pink eye every year when allergy season occurs. The other two causes of pink eye are bacteria and viruses. Pink eye caused by bacteria can be cured with antibiotics. This usually takes a few days to one week. Pink eye caused by viruses cannot be cured with antibiotics. However, your body's immune system can get the infection under control in two to three weeks. Bacterial and viral conjuctivitis are contagious. It is often recommended that anything that comes in contact with the infected eye(s) be washed (such as towels, and clothing), as well as surfaces the infected individual may have touched, such as countertops and doorknobs. In addition, if cosmetics, false eyelashes, or contact lenses are used by the infected person, it is recommended that they be discarded. Viral conjunctivitis is the more common of these two types. Although the symptoms of viral conjuncitvitis begin to go away after a week, the virus is still present in the body for as long as a month. For this reason, children and adults are recommended to stay home for at least a week after contracting the infection. The answer to your question depends on which agent caused the conjunctivitis (environmental or biological). For conjunctivitis caused by biological agents (bacteria or viruses), the answer also depends on which organism caused the infection. There are many kinds of bacteria and several viruses that cause conjunctivitis. It is usually not the case that a virus or bacterium has been hanging out in someone's make-up or on a countertop for months waiting to cause conjunctivitis. You are more likely to get this condition from direct or indirect immediate contact from someone who already has the condition. There are several web sites sponsored by hospitals or eye clinics detailing this condition, here are a few: http://www.mckinley.uiuc.edu/health-info/dis-cond/commdis/conjunct.html http://www.revoptom.com/handbook/SECT2B.HTM http://www.aafp.org/afp/980215ap/morrow.html Thanks for your question!
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