At risk populations include:
Hospital patients
Many MRSA infections occur in hospitals and healthcare facilities, with a higher incidence rate in nursing homes or long-term care facilities. Rates of MRSA infection are also increased in hospitalised patients who are treated with quinolones. Healthcare provider-to-patient transfer is common, especially when healthcare providers move from patient to patient without performing necessary hand-washing techniques between patients.
Prison inmates
In confined environments such as prisons, with continual admission of new members who may typically be in poor health and adopt poor hygiene practices, there have been a number of challenges reported first in the U.S. and then in Canada. The earliest reports were made by the CDC in state prisons. Subsequently reports of a massive rise in skin and soft tissue infections were reported by the CDC in the Los Angeles County Jail system in 2001, and this has continued. Pan et al. reported on the changing epidemiology of MRSA skin infection in the San Francisco County Jail, noting the MRSA accounted for >70% of S. aureus infection in the jail by 2002. Lowy and colleagues reported on frequent MRSA skin infections in New York State Prisons. Two reports on inmates in Maryland have demonstrated frequent colonization with MRSA.
In the news media hundreds of reports of MRSA outbreaks in prisons appeared between 2000 and 2008. For example, in February 2008, The Tulsa County Jail in the U.S. State of Oklahoma started treating an average of twelve Staphylococcus cases per month. A report on skin and soft tissue infections in the Cook County Jail in Chicago in 2004-5 demonstrated that MRSA was the most common cause of these infections among cultured lesions and furthermore that few risk factors were more strongly associated with MRSA infections than infections caused by methicillin-susceptible S. aureus. In response to these and many other reports on MRSA infections among incarcerated and recently incarcerated persons, the Federal Bureau of Prisons has released guidelines for the management and control of the infections although few studies provide an evidence base for these guidelines.
People in contact with live food-producing animals
Cases of MRSA have increased in livestock animals. CC398 is a new clone of MRSA that has emerged in animals and is found in intensively reared production animals (primarily pigs, but also cattle and poultry), where it can be transmitted to humans. Although being dangerous to humans CC398 is often asymptomatic in food-producing animals.
Athletes
In the United States, there have been increasing numbers of reports of outbreaks of MRSA colonization and infection through skin contact in locker rooms and gyms, even among healthy populations. A study published in the New England Journal of Medicinelinked MRSA to the abrasions caused by artificial turf. Three studies by the Texas State Department of Health found that the infection rate among football players was 16 times the national average. In October 2006, a high school football player was temporarily paralyzed from MRSA-infected turf burns. His infection returned in January 2007 and required three surgeries to remove infected tissue, as well as three weeks of hospital stay.MRSA has also been found in the public school systems throughout the country.
Children
MRSA is also becoming a problem in pediatric settings, including hospital nurseries. A 2007 study found that 4.6% of patients in U.S. health care facilities were infected or colonized with MRSA.
