Methicillin-resistant Staphylococcus aureus (MRSA) colonization means a person is carrying antibiotic-resistant bacteria that cause an infection called MRSA. A person who is colonized with MRSA may have the bacteria on his skin or even inside his nasal passage. He is not infected with it, however, and does not show the typical signs of infection. Though a person with MRSA colonization is not infected with the bacteria, it is possible for him to spread the bacteria to others, and he may eventually develop an infection himself. Anyone may be colonized with the bacteria, but hospital workers may be more at risk.
MRSA is a very serious infection that typically starts out as small blemishes that look like pimples or boils. Eventually, however, they may develop into deep sores that cause a great deal of pain. In some cases, the infection spreads, and the unlucky victim develops infection in his bones, heart, lungs, or even his bloodstream. Unfortunately, the antibiotics that are usually used to treat bacterial infections may prove ineffective when MRSA is involved, and doctors must try other alternatives; this may involve draining the infection instead of or in addition to treating it with drugs. A MRSA-infected person has symptoms of the disease, but a person who is colonized with the infection does not.
A person with MRSA colonization does not have MRSA and does not need treatment for infection. In many cases, however, an individual who is colonized with the staph bacteria may be treated anyway. This is due to the fact that he may be more likely to develop MRSA because of the colonization. Likewise, he may be able to spread the bacteria to others who are neither colonized nor infected.
Many people who are MRSA colonized have the bacteria in their nostrils. The bacteria may, however, appear in other places as well. For example, a person may be MRSA colonized in his respiratory tract, in sores, in the groin area, and in his urinary tract. The skin, even where it is unbroken or unmarred by sores, is also a frequent site for colonization with antibiotic-resistant bacteria. Even the rectum may be a site of MRSA colonization.
Interestingly, MRSA colonization may not always cause infection. A person may be colonized for a short period, such as a few weeks, or years at a time. It is difficult, if not impossible, to predict when and if colonization will give way to infection.