Rifampin-resistant, isoniazid-susceptible TB in HIV patients.

lishment of a biofilm, which can be avoided by disinfection of the machine with a solution of chlorine (250 ppm). We apply chlorine disinfection in our systems every 2 weeks. The water filter is replaced weekly by a sterilized 0.2 μm membrane filter. The literature mentioned in Russell’s review, the results from our experiments, and the precautions for recontamination mentioned above made us decide to change the Cidex in the Wassenburg machines every 2 weeks, starting on the first day of the week. Our investigations showed that every new disinfecting machine that uses glutaraldehyde must be tested and/or validated for daily use.