High levels of toxigenic contamination of hospital environments: a hidden threat in hospital-acquired infections in Kenya.

INTRODUCTION

The contribution of (formerly ) to the burden of hospital-associated infections (HAIs) remains undetermined in many African countries.

AIM

This study aimed to identify a sensitive and readily adaptable detection assay and to evaluate the HAI risk in Kenya.

METHODOLOGY

Sterile swabs in neutralizing buffer were used to sample equipment or surfaces that patients and clinical staff touched frequently. These swabs were either plated directly on chromogenic agar or cultured in an enrichment broth before plating. The swab suspensions, enrichment broth and plate cultures were screened by quantitative PCR (qPCR) to determine the most efficient detection method. The HAI risk was evaluated by testing the -positive samples by qPCR for the A, B and binary toxins.

RESULTS

was detected on 4/57 (7.0 %) equipment and surfaces by direct culture. The additional enrichment step increased the detection rate 10-fold to 43/57 (75.4 %). In total, 51/57 (89.5 %) environmental samples were positive for detected through either culture or qPCR. The genes encoding the primary toxins, and , were detected on six surfaces, while the genes encoding the binary toxins, and , were detected on 2/57 (3.5 %) and 3/57 (5.3 %) surfaces, respectively. Different toxin gene profiles were detected: the - gene profile on 4/10 (40 %) high-touch surfaces, + on 3/10 (30 %) surfaces, on 2/10 (20 %) surfaces and on one high-touch surface.

CONCLUSION

The widespread contamination of hospital environments by toxigenic gives a strong indication of the high risk of infections (CDIs). The two-step culture process described can easily be adapted for monitoring hospital environment contamination by .