MRSA: Comparison of UK and US Mortality Rates Yield Interesting Trends

The Resurgence of MRSA: Potential for a public health crisis

In 1961, there were reports from the United Kingdom of S.aureus isolates that had acquired resistance to methicillin (1, 2, 4,12). Later that year, isolates were recovered in from other European countries, Japan, Australia and the US. Isolates refer to the restriction of movement of a patient with a communicable disease or infection so that cross-infection to other patients is prevented. This process is also done to protect the patient and other staff members from other infectious microorganisms. MRSA has been a major problem for hospitals and nursing homes worldwide. For elderly persons in nursing homes, Stapphylococcus aureus are a significant cause of morbidity and mortality (10, 11, 12 and 13). There is a body of evidence that seems to suggest that asymptomatic MRSA carriage has been common, but patients do not appear to have the same risk for acquiring the organism. This may explain the correlation to recent events in New Jersey, New York and Michigan (9, 11).

Methicillin-resistant Staphylococcus aureus (MRSA) is a biological agent responsible for difficult to treat infections in humans. MRSA is a variation of Staphylococcus aureus, a common bacterium, which has evolved the ability to survive treatment with beta-lactum antibiotics. These antibiotics may include penicillin and methicillin. The rationale for MRSA being categorized as a potential health crisis is due to unique adoption of the organism in isolates in hospital environments (5, 6, and 7). Hospitals and nursing homes have been challenged for years on appropriate infection control procedures, as the organism becomes increasingly complex. Consequently, the origins of major MRSA clones appear to be poorly understood. A number of studies show that some MRSA’s are very divergent. The implications for this observation are intriguing.

According to Centers for Disease Prevention and Control (CDC) the estimated number of people developing a serious MRSA infection in 2005 was 94, 360 (13). Approximately 18,650 persons died during a hospital stay in 2005. As of July 2007, the population for the United Kingdom was 60,000,000 (14) compared with United States, 301, 139, 947 (15). According to the Office of National Statistics, there 1,629 deaths related to MRSA. Death rose from 51 in 1993 to 1, 629 (Figure I). The increase in deaths may be attributed to better reporting from hospitals and nursing homes respectively in the United Kingdom. Incidentally, most deaths reported in the UK occurred among the elderly and male. Compared with overall rates in the US, which according to the CDC, occurred highest among older persons, black and male. Older persons were categorized as > 65 years of age. Comparing mortality rates among both countries seemed useful. Considering that the UK first reported MRSA in 60’s. Another compelling data point to mention is that 3 to 5% of the 15 million long-term care residents in the US will acquire MRSA (16). The numbers result in 150, 000 to 750,000 infections annually (4, 16). These numbers are staggering. Most of the infections identified in US nursing homes were caused by S.aureus, the second most common cause of bacteremia. Several studies have questioned if nursing homes in US have the wherewithal to address MRSA appropriately. Consequently, a significant number of long-term care residents who transfer from acute care hospitals are colonized with MRSA. This creates additional challenges for the nursing home staff and their respective infection control protocols. Multi locus sequence typing is a nucleotide sequence based approach. The ability to examine isolates of bacteria and other organisms is paramount. In combination with multi locus enzyme electrophoresis sequencing (MLEE) may further tease out MRSA organism behavior in elderly men in both countries.

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11. Office for National Statistics. (2005). MRSA Deaths continue to rise in 2005. Figure I. Retrieved from on October 24, 2007.
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13. Centers for Disease Control and Prevention. (2007). Invasive MRSA Fact Sheet. Retrieved from on October 24, 2007.
14. World Statesmen. [Online]. United Kingdom. Retrieved from on October 24, 2007.
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16. American Society for Microbiology. (2005). Extraordinarily High MRSA Rates in Nursing. 45th ICAAC Meeting of the American Society of Microbiolgy. Washington DC. Retrived from on October 24, 2007.

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