Inactivation of Brucella Suis, Burkholderia pseudomallei, Francisella tularensis, and Yersinia pestis using Vaporous Hydrogen Peroxide

Abstract

This study evaluated the inactivation of Brucella suis, Burkholderia pseudomallei, Francisella tularensis, and Yersinia pestis on glass, Hypalon ® rubber glove, and stainless steel using vaporous hydrogen peroxide fumigation of a ~15 m 3 chamber. A suspension of approximately 1 x 10 8 colony forming units (CFU) of each organism was dried on coupons of each type of test surface and exposed to vaporous hydrogen peroxide. A significant reduction in the log10 CFU of each organism on all test materials was observed between the controls evaluated after a 1-hour drying time and unexposed controls evaluated after decontamination. For all organisms, qualitative growth assessments showed that vaporous hydrogen peroxide exposure completely inactivated bacterial viability on all replicates of the test materials incubated up to 7 days post-exposure. In parallel, all Geobacillus stearothermophilus biological indicators (BI) exposed to vaporous hydrogen peroxide exhibited no growth after 1 and 7 days incubation. This study provides information on using a combination of quantitative and qualitative growth assessments to evaluate vaporous hydrogen peroxide for the surface decontamination of B. suis, B. pseudomallei, F. tularensis, and Y. pestis within a large-scale chamber. ArticlesInactivation of Brucella suis, Burkholderia pseudomallei, Francisella tularensis, and Yersinia pestis Using Vaporous Hydrogen Peroxide

Evaluation of Biological Indicator Spores as Tools for Assessment of Fumigation Decontamination Effectiveness

“…One explanation might be that these virus species were present in the lowest titers, with the exception of ERAV-1, but the log 10 reduction of bacteria, virus, and bacterial spores present in higher titers was lower than for the enveloped virus species BVDV and LPAI. This indicates that the decontamination procedure was not powerful enough to reduce the other microorganism titers 4 log 10 or more, which is inconsistent with other studies where VHP is considered an effective disinfection method against related microorganisms (Rogers et al, 2010). Previous studies point out the significance of the titer of the test organisms for the result of the disinfection, at least in suspension tests, which might be one explanation for the low efficiency of VHP observed in this study as the concentration of the test organisms before disinfection is relatively high (Johnston et al, 2000).…”

“…However, formaldehyde has carcinogenic and allergenic properties and due to this, FA is used in a more restrictive way today than previously and less harmful alternatives have been explored (Epizone, 2011). One of the alternatives to FA is vaporized hydrogen peroxide (VHP) (Bentley et al, 2012;Johnston et al, 2005;Rogers et al, 2010). The disinfection mechanism of hydrogen peroxide is based on the release of free oxygen radicals that react with proteins, lipids, and nucleic acid (McDonnell & Russell, 1999;Pottage et al, 2010).…”

Persistence and Inactivation ofBurkholderia malleiChina 7 Deposited on Nonporous Laboratory Materials

“…Several studies have demonstrated the inactivation of B mallei in water and that deposited on surfaces 7,12 –18 ; however, there is currently no criterion established for determining an appropriate level of decontamination for B mallei . As noted previously for other biological agents, 9,10,19 –21 complete inactivation may be a suitable requirement following remediation. In the present study, B mallei inoculated onto glass, rubber glove, and stainless steel and exposed to vaporous hydrogen peroxide was decontaminated >6 logs, as demonstrated by the lack of growth (no turbidity) in liquid cultures after 7 days of incubation.…”

“…The decontamination procedure was performed with the VHP 1000ED Biodecontamination System (STERIS Corporation), in which fumigation parameters were used as previously described. 8,9 Briefly, the decontamination process consisted of dehumidification (10 minutes; ≤6.9 mg/L, relative humidity), conditioning (20 minutes; 6.5 g/min, hydrogen peroxide), decontamination (5.5 hours; 5.0 g/min, hydrogen peroxide), and aeration phases (>4 hours), which were all controlled by the hydrogen peroxide generator. Four 12-inch fans were placed inside the test chamber to provide turbulence for maximizing vaporous hydrogen peroxide distribution.…”

“…Following the 1 hour of drying, the coupons were transferred into a 15-m 3 BSC III as previously described. 8,9 In parallel, Spordex VHP Biological Indicators (STERIS Corporation, Mentor, Ohio) containing Geobacillus stearothermophilus spores and VHP Chemical Indicator NB305 Strips (STERIS Corporation) were used to verify the decontamination process. Sixteen biological and chemical indicators were placed at separate locations within the ARCA chamber and subjected to decontamination; as a positive control, a single biological indicator and chemical indicator were affixed to the outside of the test chamber that was not decontaminated.…”