Infection-control specialists at the National Institutes of Health's Clinical Center said a New York City patient carrying a multidrug resistant strain of Klebsiella pneumoniae -- a microbe frequently associated with hospital-borne infections -- was admitted to the 243-bed research hospital while participating in a clinical study.
Although a nurse noted the patient's drug resistant strain of Klebsiella pneumoniae and immediately isolated the woman and implemented enhanced infection-control practices, K. pneumoniae began to spread to other Clinical Center patients at about one case per week.
Multidrug resistant K. pneumoniae is among the more dreaded infections because there are few effective treatments and it has a mortality rate of 40 percent.
Enhanced infection-control practices included not only hand washing, masks and gowning medical personnel -- it also involved nurses only treating the infected patients, building a wall, using a vapor of hydrogen peroxide to sanitize rooms and removing sinks and drains where K. pneumoniae had been detected.
The original patient recovered but the infection ultimately colonized 17 patients. Eleven died -- six from the infection and five from their underlying disease.
Dr. Tara N. Palmore, the NIH Clinical Center's deputy hospital epidemiologist, said traditional tests to detect the strain of the infection were of no use, so the hospital teamed with Julie Segre and other National Human Genome Research Institute researchers to use genome sequencing to learn how the microbe spread.
A report published in the online edition of Science Translational Medicine said the hospital found the K. pneumoniae from the first patient was the same strain as the one that infected the second patient and the others.