DIFFICIL-S^® has been independently tested by NHS laboratories at a dilution rate of 1:400 to give at least a 5 log reduction of 99.999% in Clostridium difficile (including spores), MRSA, Listeria, E.coli, Salmonella, Pseudomonas, Mycobacteria (tubercle bacilli), Norovirus and other pathogens.