Blog | Wednesday, September 18, 2013

The copper kerfuffle


Several months ago we invited a guest post from Stephan Harbarth and Matthias Maiwald, a post that questioned the biological plausibility of a recently published clinical trial of copper surfaces that claimed a more than 50% reduction in the rate of health care-associated infection (HAI) and/or MRSA-VRE colonization. Now Harbarth, Maiwald and Stephanie Dancer have published a more extended critique of the study in a letter-to-the-editor in the September issue of Infection Control and Hospital Epidemiology. I encourage you to read the letter, and the reply from the authors, and make up your own mind about the validity of the findings and the transparency with which the authors reported their outcomes.

My two cents: The authors have been caught out in a case of selective reporting (or at least egregious obfuscation) of their outcomes, and it would probably have been better for them not to issue a reply (mostly because the reply is not persuasive).

The reply claims that “any HAI” wasn’t reported because it would have also included some patients with colonization, and the development of infection versus colonization may be biologically different. But it is still OK to report the outcome “HAI and/or colonization”? They also make the case that Harbarth, et al cannot question the biological plausibility of their findings because they themselves have also argued that the environment is a source of HAI pathogens. This of course misses the point entirely. Harbarth, et al aren’t arguing that the environment has no role, they are arguing that it is implausible, given what we know about the pathogenesis of HAIs, that the environment has the major role suggested by the findings of this study.

A well-designed, persuasive, multicenter, randomized controlled trial that demonstrated a greater than 50% reduction in HAI by changing high-touch surface composition should have been published in a very high impact journal (e.g. JAMA, the New England Journal of Medicine, The Lancet), and the findings should have been front-page news in major media outlets. Alas, that didn’t happen with this study, for some of the reasons outlined in the letter by Harbarth, et al.

Daniel J. Diekema, MD, FACP, practices infectious diseases, clinical microbiology, and hospital epidemiology in Iowa City, Iowa, splitting time between seeing patients with infectious diseases, diagnosing infections in the microbiology laboratory, and trying to prevent infections in the hospital. This post originally appeared at the blog Controversies in Hospital Infection Prevention.