A systematic review of chlorine-based surface disinfection efficacy to inform recommendations for low-resource outbreak settings.

BACKGROUND

Infectious diseases can be transmitted via fomites (contaminated surfaces/objects); disinfection can interrupt this transmission route. However, disinfection guidelines for low-resource outbreak settings are inconsistent and not evidence-based.

METHODS

A systematic review of surface disinfection efficacy studies was conducted to inform low-resource outbreak guideline development. Due to variation in experimental procedures, outcomes were synthesized in a narrative summary focusing on chlorine-based disinfection against 7 pathogens with potential to produce outbreaks in low-resource settings (Mycobacterium tuberculosis, Vibrio cholerae, Salmonella spp., hepatitis A virus, rotavirus, norovirus, and Ebola virus).

RESULTS

Data were extracted from 89 laboratory studies and made available, including 20 studies on relevant pathogens used in combination with surrogate data to determine minimum target concentration × time ("CT") factors. Stainless steel (68%) and chlorine-based disinfectants (56%) were most commonly tested. No consistent trend was seen in the influence of chlorine concentration and exposure time on disinfection efficacy. Disinfectant application mode; soil load; and surface type were frequently identified as influential factors in included studies.

CONCLUSIONS

This review highlights that surface disinfection efficacy estimates are strongly influenced by each study's experimental conditions. We therefore recommend laboratory testing to be followed by field-based testing/monitoring to ensure effectiveness is achieved in situ.