Fast, broad-range disinfection of bacteria, fungi, viruses and prions

Abstract

Effective disinfectants are of key importance for the safe handling and reprocessing of surgical instruments. This study tested whether new formulations containing SDS, NaOH and 1-propanol (n-propanol) are simultaneously active against a broad range of pathogens including bacteria, fungi, non-enveloped viruses and prions. Inactivation and disinfection were examined in suspension and on carriers, using coagulated blood or brain homogenate as an organic contaminant. Coomassie blue staining was used to assess whether the formulations undesirably fixed proteins to rough surfaces. A mixture of 0.2 % SDS and 0.3 % NaOH in 20 % n-propanol achieved potent decontamination of steel carriers contaminated with PrP TSE , the biochemical marker for prion infectivity, from 263K scrapie hamsters or from patients with sporadic or variant Creutzfeldt-Jakob disease. 263K scrapie infectivity on carriers was decreased by ¢5.5 logs. Furthermore, the formulation effectively inactivated poliovirus, hepatitis A virus and caliciviruses (including murine norovirus) in suspension tests. It also yielded significant titre reductions of bacteria (Enterococcus faecium, Mycobacterium avium; .6 logs), fungi (spores of Aspergillus niger; ¢5 logs) and poliovirus (.4 logs) embedded in coagulated blood on carriers. The formulation was not found to fix proteins more than was observed with water as the cleaning reagent. In conclusion, SDS, NaOH and n-propanol can synergistically achieve fast, broad-range disinfection.

Inactivation of Caliciviruses

“…Inactivation by alcohols of caliciviruses on coupons (including skin) and in solution has been addressed in numerous studies [8,9,31,67,68,69,70,71,72,73,74,75,76,77,78]. Selected calicivirus inactivation results determined in coupon studies (virus dried onto surfaces) and in solution studies have been displayed in Table 6.…”

“…There is extensive literature describing the inactivation of caliciviruses by other classes of disinfectants, including aldehydes [8,31,72,79,88,112,113,114], quaternary ammonium compounds [8,69,75,76,79,81,82,85,103,107,113], surfactants [8,69,73,112,113], sodium hydroxide [31,79], and other chemicals [103,115,116]. The calicivirus inactivation efficacy information for these agents determined in coupon studies (virus dried onto surfaces) and in solution studies is summarized in Table 8.…”

Prions and endotoxins: reprocessing strategies for reusable medical devices

“…These two categories of chemicals should be avoided in the decontamination step early in the prion inactivation process (Rutala and Weber, 2010). Cleaners whose formulations include sodium dodecyl sulfate (SDS) show promise with ≥ 5.5 log 10 LD 50 reductions in prion activity (Peretz et al ., 2006;Beekes et al ., 2010). Given the wide variety of alkaline and enzyme cleaners, it is important to validate the effi cacy of the cleaner of choice as part of a comprehensive validation experiment when developing a prion inactivation strategy that uses contemporary proprietary chemicals.…”

Evaluation of a combinatorial approach to prion inactivation using an oxidizing agent, SDS, and proteinase K

“…Prior investigations have demonstrated minimal effects on CJD infectivity [14], but up to a 3 log 10 reduction on scrapie infectivity [15]. More recently, SDS in combination with NaOH has been shown to successfully inactivate the 263 K hamster scrapie agent, resulting in a > 5.5 log 10 reduction in infectivity [16,17]. Proteases have also been reported to have prion inactivation potential [18-22].…”