Cepheid's GeneXpert MRSA 50-minute test was FDA cleared in 2007 for rapid point-of-care detection. The tests are being used by hospitals to identify carriers upon admission so infection control teams can concentrate their efforts on known carriers.
Antibiotics were a miracle drug when introduced more than 60 years ago, but they have also spurred the proliferation of antibiotic-resistant strains of super bug bacteria that hospitals are having a tough time controlling.
About 1.7 million Americans each year develop infections from various germs while hospitalized and about 95,000 of them die, according to the U.S. Centers for Disease Control and Prevention (CDC). The five most common hospital-acquired infections (HAIs) include ventilator-associated pneumonia, bloodstream infections caused by a catheter, urinary tract infections caused by catheter, Methicillin-resistant Staphylococcus aureus (MRSA) and Clostridium difficile bacteria, which effects intestinal tract. Of these, MRSA is the biggest single killer, claiming about 19,000 lives per year. The CDC recently reported MRSA infections now cause more deaths per year in the U.S than HIV/AIDS.
A 2007 study conducted by the Association for Professionals in Infection Control and Epidemiology (APIC) of 1,237 hospitals and residential healthcare centers showed antibiotic resistant breeds of staph are much more prevalent among hospital patients in the U.S than
previously thought. Researchers found 3.4 percent of patients were infected with MRSA, a rate nearly nine times greater than estimated by the CDC in 2005.
MRSA was unknown until the 1970s and infections have steadily risen since, now accounting for 50-70 percent of all staph infections acquired in U.S. hospitals, the report states.
The percentage of 50-70 percent of skin infections being MRSA was confirmed by the emergency department at Wake Forest University Baptist Medical Center, which sees about 300-350 patients patients a day, and on average about 30 present with skin infections, said Bret A. Nicks, M.D., assistant professor, assistant medical director, department of emergency medicine, Wake Forest University Baptist Medical Center, and a member of the PR committee of the American College of Emergency Physicians.
“It’s amazing how high it is,” he said.
Dr. Nicks said the best defense hospitals can adopt to stop the spreading infections is having the entire staff adhere to strict hand-washing before and after seeing patients and to develop an infection control policy. However, he says clinicians often get sidetracked with many demands, especially in ERs, and sometimes they forget to wash or sterilize their hands in between duties.
“Having good policies in place is one thing, but good adherence to those policies is something else,” Dr. Nicks said.
Detecting MRSA carriers
Hospitals can save money and staff time by concentrating their infection control and isolation efforts on patients who are known to be infected or are carriers of MRSA. The standard tests for MRSA detection can take 48 hours or more to complete, but new self-contained nasal swab tests can produce results within 50 minutes to two hours so hospitals can quickly identify high-risk patients.
Cepheid’s GeneXpert MRSA 50-minute test was FDA cleared in 2007 for rapid point-of-care detection. Donna Lemmert, RN, CIC, infection control coordinator, Baltimore Washington Medical Center, has been using it since August 2007. The hospital limits its testing to patients who are going in to surgery or who fall into groups considered to be high-risk as MRSA carriers. These include critical care patients, nursing home residents, anyone transferred from another hospital, on antibiotics, or who has a previous history of MRSA infections.
“There are certain groups that are at greater risk of being carriers of MRSA,” Lemmert said. “It really isn’t practical to test everyone, because not everyone is a carrier or at risk.”
She says about 8-15 percent of critical care pre-admissions are colonized with MRSA, most of which would have gone undetected prior to using the Xpert testing.
“We have a whole lot more people on contact precautions than we had in the past,” Lemmert said. “It is a safety net for the other patients.”
When a MRSA carrier is found, the hospital’s infection control staff issues a warning for staff to take contact precautions when dealing with the patient, such as hand washing and/or use of an alcohol-based hand sanitizer after touching patients, and cleaning all equipment after use in the patient’s room. Lemmert said identifying MRSA carriers helps to concentrate infection control attention on them and anything they come in contact with to prevent spreading the germs.
“Once you are aware of the number of people coming in with MRSA it is an eye opener,” said Gary Fritz, medical technology administrative director of the laboratory at Baltimore Washington Medical Center.
Lemmert said patients are swabbed both before admission and during discharge to help monitor if patients carry MRSA or if they may have contracted it at the hospital. This could prove more important after October 2008 when Medicare and Medicaid will not longer pay for costs associated with treating HAIs.
James Bowden, M.D., MBA, FAAFP, chief medical officer for Holston Valley Medical Center, Kingsport, TN, started using Cepheid’s GeneXpert MRSA in January. To start, Dr. Bowden said only patients considered high-risk are tested, including transfers from rehabilitation centers, other hospitals, nursing homes and patients identified as former carriers by their medical records. He said most patients in these groups are placed in isolation until it is confirmed they do not carry MRSA.
The BD GeneOhm MRSA assay uses a nasal swab and can identify carriers within two hours. The University College London Hospital National Health Service Foundation Trust (UCLH) conducted a study using this test to see if the rapid screenings could reduce infection rates. A study of about 19,000 surgical patients at the hospital concluded it helped reduce MRSA blood infection rates by nearly 40 percent.
The Pennsylvania Patient Safety Authority (PSA), which oversees the state’s mandatory safety error reporting program, said of the hospitals that conduct
pre-admission MRSA testing, about 13 percent of patients are found to be MRSA carriers. However, PSA also said the information about the infection was not always communicated to other healthcare workers at the hospitals.
The British MRSA solution
The alarming rise in MRSA infections in the United Kingdom prompted the British Department of Health to fight back the tide with new programs and funding that started in 2005. There is a 23 percent mortality rate among British patients with MRSA bloodstream infections. In the early 1990s, 2 percent of staph blood infections were due to MRSA in the U.K., but that figure is now about 45 percent. The U.K. rate of MRSA bloodstream infections are among the highest in Europe.
The government introduced several anti-MRSA programs since 2004 and set a target of reducing these rates 50 percent by 2008 compared to 2003-2004 base rates. Government health agencies said last year there has been about a 20 reduction of MRSA across all U.K. hospitals since implementing the new programs. A report on the progress of the efforts published in December looked at MRSA rates between 2001 and 2006 and found a 27 percent decrease in the probability that a patient will acquire MRSA.
To accomplish this decrease the Department of Health introduced the “clean your hands campaign,” offering support to hospitals facing the biggest infection
challenges and improving the quality and infection prevention training of temporary staff. The “clean your hands campaign” was launched in September 2004 and British officials say it was instrumental in raising infection control awareness.
Last September, the Department of Health created rules banning doctors' traditional white coats and required hospitals to adopt a “bare below the elbows” dress code. The rules call for only short sleeve shirts, but also ban wristwatches, rings, bracelets and neckties when carrying out clinical activity. New rules were also created for isolating patients who are infected with Clostridium difficile or MRSA. A legal requirement now requires all chief executives of health facilities to report MRSA and Clostridium difficile infections to the Health Protection Agency (HPA) or face fines.
In November, funding was made available for deep cleaning of all National Health Service (NHS) hospitals in England, which was supposed to be completed by March 2008. In January, the NHS announced new funding so all its hospitals can hire two new infection control nurses, two isolation nurses and an antimicrobial pharmacist.
In February, a campaign was launched to remind the public and doctors that antibiotics are not effective on many ailments and is causing the emergence of antibiotic-resistant bacteria.
The cost of the initiatives totals an investment of about $500 million per year
by 2011.
“We have gone from what has been described by the HPA as ‘a seemingly unstoppable rise in MRSA bloodstream infections throughout the 1990s’ to a 10 percent fall in cases of MRSA,” said National Health Secretary Allen Johnson,
following the additional staff funding announcement in January. “Patients have my assurance that the government will not take its foot off the pedal and will continue to do all we can to tackle infection.”