Two new interesting papers in ICHE, both of significance I think. The first from Kings’ College Guy’s and St Thomas’ in London examines the degree of environmental contamination from patients with diarrhoea and toxigenic C. difficile but undetectable toxin. These patients are called a “potential Clostridium difficile excretor” in some papers. In this study, Biswas and colleagues (including Jon Otter and Simon Goldenberg) demonstrated that C. difficile was recovered from 49% of rooms from patients producing toxin and from 34% of the rooms of “potential Clostridium difficile excretor” group. Call me ‘Mr Picky’ but at what level of contamination does ‘potential’ become actual? 13% of sites tested in the ‘potential’ group were positive (around half that of the CDI group). So, actual infection seems to cause more contamination, which if patients are having more bowel movements I would accept, but the level of contamination from those without toxin production is, I would say significant (not forgetting that the toxin test is as reliable as flipping a coin). The authors are right, all excretors are a risk and we should not shrink from efforts to detect them. Thinking further, It would be interesting to see if the level of contamination could be linked with the frequency of bowel movements (and possibly the Bristol stool chart score?). Should be possible if nursing records are reliable (ahem..). Without getting too graphic there would likely be a splatter factor. Should we increase cleaning frequency for patients with multiple type 7 stools in a day?
The second paper looked at the association between hospital room square footage and acquisition of CDI, showing an Odds Ratio of 3 for every increase of 50 square feet. Interesting, possibly effective cleaning is more difficult in a large space, the cleaning equipment is recontaminating or any disinfectant is losing efficacy? What are the implications for multi-occupancy bays as in the UK? Still lots to learn about the environment.