MRSA is caused by a strain of Staphylococcus aureus (S. aureus) bacteria or usually called “staph“. S. aureus is a common type of bacteria that normally lives on the skin and sometimes in the nose. MRSA is difficult to treat than most staph Because it’s resistant to some commonly used and powerful antibiotics such as penicillin (see antibiotic resistance). Staph aureus is common and generally about 30 percent of all people are colonized with staph at any given time. There are two types of MRSA:

• Healthcare-associated MRSA (HA-MRSA) infections occur in people who are or have recently been in the hospital. A person who is hospitalized or had surgery within the past year are at increased risk. MRSA bacteria are largely responsible for most of hospital-acquired staph infections.

• Community-associated MRSA (CA-MRSA) infections are ones that occur in otherwise healthy people who have not recently been in the hospital. The infections have occurred among athletes who share equipment or personal items (example: towels or razors) and children in daycare facilities. Members of the military and those who get tattoos are also at risk. The number of CA-MRSA cases is increasing.

Many ordinary people already have MRSA bacteria living on their skin or in their noses. These people are known as carriers, they do not showed any symptoms, but they do carry the disease to other people ( non-carriers ). While 25 percent to 30 percent of the population carries staph, it is estimated that 1 percent carries MRSA, according to CDC.

Normally the bacteria they carry do not cause major health problems unless the bacteria manage to enter the body through wounds or open skin. Even then, it usually only result in minor skin conditions, such as acne pimples. However, when the susceptible populations identified above come into direct contact with carriers, there is a large potential for them to develop severe staph infections and serious disease.

A report by the CDC estimated that MRSA has been responsible for the deaths of 11,000 – 17,ooo in 2007 in the United States. This number are higher than  annual AIDS fatality in the same year.