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Endospores are non-reproductive structures that develop inside bacteria. Spore forming bacteria are tough. These species, which include Bacillus, Clostridioides and Clostridium, can surround themselves with durable coats of protein that allow them to survive in hostile environmental conditions. As spores, bacteria can remain dormant for years, protected from chemical and heat stresses.

Scope of problem

In combating Clostridium difficile (C. diff) not only are strains of the bacteria becoming antibiotic resistant, the spores themselves are resistant to many disinfectant products. C. diff infections can create a frustrating and complex challenge for healthcare facilities – patients who are admitted for one problem and receive antibiotic treatment can, in turn, become a greater risk for infection by other pathogens they come in contact with. Today, approximately 80 percent of C. diff infections remain healthcare-associated with the majority impacting patients in the expanding population of people over the age of 60.

Clostridium difficile

In healthcare settings, Clostridioides (Clostridium) difficile (C. diff), whose symptoms range from diarrhea to life-threatening inflammation of the colon has emerged as a significant threat. C. diff can be found on surfaces, devices, or material (e.g. commodes, bathing tubs, etc.) that becomes contaminated with feces. In its endospore form, C. diff can remain viable on surfaces for several weeks, even months. C. diff spores are transferred to patients mainly via the hands of healthcare personnel who have touched a contaminated surface or item.

This chart shows the surface disinfection performance by a single Klaran WD Series UVC LED against C. diff on a stainless steel surface. The UVC LED device is mounted 1 cm above the contaminated surface to provide an intense disinfection irradiance. Unlike mercury-based UVC sources which radiate heat, UVC LEDs transfer heat from the non-emitting side of the device which enables intense proximal configurations.