Community Environmental Contamination of Toxigenic Clostridium difficile

Clostridium difficile infection is often considered to result from recent acquisition of a C difficile isolate in a healthcare setting. However, C difficile spores can persist for long periods of time, suggesting a potentially large community environmental reservoir. The objectives of this study were to assess community environmental contamination of toxigenic C difficile and to assess strain distribution in environmental versus clinical isolates.

From 2013 to 2015, we collected community environmental swabs from homes and public areas in Houston, Texas to assess C difficile contamination. All positive isolates were tested for C difficile toxins A and B, ribotyped, and compared with clinical C difficile isolates obtained from hospitalized patients in Houston healthcare settings.

A total of 2538 environmental samples were collected over the study period. These included samples obtained from homes (n = 1079), parks (n = 491), chain stores (n = 225), fast food restaurants (n = 123), other commercial stores (n = 172), and hospitals (n = 448). Overall, 418 environmental isolates grew toxigenic C difficile (16.5%; P < .001) most commonly from parks (24.6%), followed by homes (17.1%), hospitals (16.5%), commercial stores (8.1%), chain stores (7.6%), and fast food restaurants (6.5%). A similar distribution of ribotypes was observed between clinical and environmental isolates with the exception that ribotype 027 was more common in clinical isolates compared with environmental isolates (P < .001).

We identified a high prevalence of toxigenic C difficile from community environs that were similar ribotypes to clinical isolates. These findings suggest that interventions beyond isolation of symptomatic patients should be targeted for prevention of C difficile infection.