[News-Pharma-MRSA is on the decline]

MRSA on the wane--in the intensive-care unit, anyway


We've been hearing for some time now about the proliferation of drug-resistant staph infections caused by bacteria that are stronger than antibiotics. Today there's an indication that in at least one small portion of the universe, the infections are actually on the decline.


The rate of methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections from central lines (intravenous catheters) in hospital intensive care units (ICUs) dropped by half between 1997 and 2007, according to research in tomorrow's Journal of the American Medical Association (JAMA). It’s unclear exactly how many Americans become sick with MRSA in ICUs every year, but an estimated 94,360 Americans contracted such infections in 2005, just over a quarter of them caught in the hospital, according to CDC research published two years ago in JAMA. MRSA is responsible for 5.6 percent of all central line-caused infections.


So it’s good news, but there are a few catches: If you do catch a staph infection in the ICU, it was still more likely during the time period studied that you’d have MRSA, rather than the much more treatable methicillin-susceptible Staphylococcus aureus (MSSA).


Nor does the research, by Centers for Disease Control and Prevention (CDC) researchers, speak to the chance of catching MRSA elsewhere in the hospital — never mind outside, which is where experts say the problem is worst.


"This is just a subset of the problem and we can't use it to speak to the whole problem," says study co-author Deron Burton, a lieutenant commander in U.S. Public Health Service. "But we are seeing success in reducing MRSA risk, because while ICU patients are smaller in number, they are highly vulnerable. To see we've had dramatic decline in high-risk patients is a very exciting finding about what's happening with MRSA in the healthcare facility."


Burton added that the data doesn’t make clear why MRSA is more common in the ICU than MSSA. Overuse of antibiotics has been speculated as a possible cause.


Hospitals in recent years have tried to reduce bloodstream infections by implementing more standardized hand-washing procedures for staff, methods of inserting catheters and taking them out sooner. But the study doesn’t show which of these infection-control methods, if any, accounted for the decline in staph and other bloodstream infections in the ICU, wrote Michael William Climo of the Hunter Holmes McGuire VA in Richmond, Virginia, in an editorial accompanying the study.


What's more, fewer than 6 percent of ICUs that submitted data to the National Healthcare Safety Network, a voluntary surveillance system that monitors the infections, contributed data for the whole length of the study. And it's unknown whether MRSA bloodstream infections transmitted through ventilators, or those in the skin and soft tissue, also decreased among those hospitals.


"Clearly, ICUs … have made substantial progress at reducing hospital-acquired infections, suggesting that real change is being made," Climo wrote. "Despite this progress, most ICUs are far from the goal of zero infections."


Image of MRSA/CDC/Janice Haney Carr/Jeff Hageman via Public Health Image Library




一直以來, 抗生素往往壓不下因細菌感染引起的抗藥性葡萄球菌的增殖. 如今有跡象顯示, 至少有一小部份的感染正在衰退中.

根據JAMA的一項研究指出, 在1997~2007的十年間, 在醫院的ICU(加護病房)中, MRSA(金黃色葡萄球菌)在主血管(主靜脈)中的感染率下降了50%. 在美國, 每年在ICU中感染MRSA的人數並不好抓, 如以兩年前CDC(疾管局)在JAMA發表的資料, 單以2005年為例即有超過四分之一的住院患者, 94,360人左右. 在所有的血管主幹道感染中, MRSA約佔了5.6%左右.


這是個好消息, 然而請注意: 如果你在ICU中發生了葡萄球菌感染, 中MRSA的機率, 還是比好對付的MSSA(甲氧西林敏感金黃色葡萄球菌)多的多.


"這只是一小部份, 不能當作全面性的解答." 身為公共衛生局的官員(少校), 也是本篇研究的共同作者之一, Deron Burton表示. "但我們渴求成功地降低MRSA感染, 因為ISU病患一旦減少, 他們會更易受感染. 在醫療院所中MRSA正面臨的改變, 對於高感染風險的病患而言, 是非常令人興奮的."


Burton指出, 這份資料並未充分顯示, 在ICU裡, 為何MRSA比MSSA更為常見. 抗生素濫用被認為是主要的原因之一.


近年來, 醫院一直藉著許多程序的推動來企圖降低血液感染, 如落實醫護人員手部清潔, 以及要求導管插拔速度等. 但研究並未納入這些防治方法. 如果說有的話, 那非是Michael William Climo不可. 他在Hunter Holmes McGuire VA in Richmond, Virginia參與研究.


再者, 在一項自發性感染監督系統-National Healthcare Safety Network-的運作中, 只有不到6%的ICU有回報資料, 而它們正是整個研究的資料來源. 此外, MRSA是否可藉著通風系統, 或附著於皮膚或面紙之上來傳播, 依然是未知數, 這樣一來, 醫院的配合度也降低了.


"明顯地, ICU...在降低院內感染的貢獻上有了些實質的進展, 有些改變正在進行." Climo寫道. "儘管如此, 離零感染還有很長的路要走"





(Translated by Jacob)

Though I am far from the field of anti-biotic now, it was once my enlightenment of entering the industry.

Thank you, Lord.