Comparative evaluation of a novel fluorescent marker and environmental surface cultures to assess the efficacy of environmental cleaning practices at a tertiary care hospital.

BACKGROUND

Cleaning high-touch surfaces serves as a crucial step towards controlling the transmission of multidrug-resistant pathogens in hospital environments. The process can be made most effective if scientifically monitored using a simple, feasible and reliable technique, especially in resource-poor settings.

AIM

To identify a novel florescent marker (FM) comparable to the already existing commercial FM systems and to assess its efficacy in evaluating cleaning of high-touch surfaces in a hospital environment.

METHODS

A liquid detergent used for washing purposes was identified as a novel FM. Pre- and post-cleaning sampling were performed from 250 high-touch surfaces in different patient-care areas using this marker and aerobic colony counts. Concordance between the two methods was assessed and compared by Cohen's kappa coefficient. The sensitivity, specificity, positive predictive and negative predictive values for the new FM method were calculated against the microbiological method.

FINDINGS

A good correlation (κ = 0.60) with overall concordance of 79.6% was observed between the two methods. The sensitivity, specificity, positive predictive value and negative predictive value of the FM were 79.58% (95% confidence interval (CI): 72-85.85%), 79.63% (95% CI: 70.79-86.78), 83.70% (95% CI: 76.38-89.50) and 74.78% (95% CI: 65.83-82.38), respectively.

CONCLUSIONS

The FM used in the present study proved to be a simple and cost-effective alternative to commercially available FMs for assessing environmental cleaning practices on a daily basis in resource-poor settings. Additional studies making direct comparisons of the FM used here with the established FMs are warranted before it can be generalized for use.