TABLE 2.
Effectiveness of Various Prion Decontamination Methods Evaluated by Selected Inactivation Studies
| Publication | Year | Prion strain |
Source material |
Assay used |
Decontamination methods |
Transmission, % (infected/total) |
Log reduction |
|---|---|---|---|---|---|---|---|
| Taylor et al10 | 1997 | 22A scrapie strain | Brain macerates | VM mice, IC | Immersed in H2O, 1 h then autoclaving in H2O, 121°C; 30 min | 100 (11/11) | ... |
| Autoclaving in NaOH (2M), 121°C; 30 min | 0 (0/18) | ... | |||||
| Taylor et al11 | 1998 | 263K scrapie strain | Brain macerates | Hamsters, homogenate, IC | Autoclaving, 134°C; 18 min (1 cycle) | 100 (10/10)a | 3.3 |
| Autoclaving, 134°C; 18 min (2 cycles) | 60 (3/5)a | 4.6 | |||||
| Fichet et al14 | 2004 | 263K scrapie strain | Stainless steel wires in 10% homogenate | Hamsters, implanted | NaOCl (20,000 ppm), 20°C; 1 h | 0 (0/8) | >5.6 |
| NaOH (1N), 20°C; 1 h | 0 (0/12) | >5.6 | |||||
| Autoclaving (dry),b 134°C; 18 min | 60 (6/10) | 4 to 4.5 | |||||
| Autoclaving in H2O, 134°C; 18 min | 0 (0/11) | > 5.6 | |||||
| Yan et al15 | 2004 | 263K scrapie strain | Stainless steel wires in 10% homogenate | Hamsters, implanted | Autoclaving, 134°C; 18 min | 10 (1/10) | ... |
| NaOH (1 M) bath, 24 h then autoclaving 134°C; 18 min | 20 (2/10) | ... | |||||
| Enzymatic detergent (2%) wash then autoclaving, 134°C; 18 min | 100 (10/10) | ... | |||||
| Alkaline detergent (pH, 11) wash 70°C; 10 min then autoclaving, 134°C; 18 min | 22 (2/9) | ... | |||||
| Jackson et al16 | 2005 | RML strain | Stainless steel wires in 10% or 20% homogenate | Tg20 mice, implanted | Autoclaving, 121°C; 20 min (20% homogenate) | 33 (2/6)c | ... |
| Autoclaving, 134°C; 20 min (20% homogenate) | 25 (1/4)c | ... | |||||
| Autoclaving, 134°C; 20 min (10% homogenate) | 100 (13/13) | ... | |||||
| Peretz et al22 | 2006 | Sporadic CJD strain | Stainless steel wires in 10% homogenate | Tg23372 mice, implanted | Autoclaving, 121°C; 30 min | 0 | ... |
| Autoclaving, 121°C; 2 h | 73 | ... | |||||
| Autoclaving, 134°C; 2 h | 46 | ... | |||||
| Fernie et al17 | 2007 | 301V BSE, 263K scrapie, or 22A scrapie strains | Brain macerates | VM mice or LVG hamsters, homogenate, IC | Autoclaving, 134°C; 18 min (301V, VM mice) | 64 (9/14) | ... |
| Autoclaving, 134°C; 18 min (263K, LVG hamsters) | 13 (2/16) | ... | |||||
| Autoclaving, 134°C; 18 min (22A, VM mice) | 0 (0/15) | ... | |||||
| Giles et al21 | 2008 | 301V BSE, cattle BSE | Stainless steel wires in 10% homogenate | Tg2091 or Tg4092 mice, implanted | Autoclaving, 134°C; 2 h (301V strain, Tg 2091 mice) | 14 | ... |
| Autoclaving, 134°C; 2 h (cattle BSE strain, Tg 4092 mice) | 89 | ... | |||||
| Lehmann et al18 | 2009 | 263K scrapie strain | Stainless steel wires in 20% homogenate | Hamsters, implanted | Autoclaving, 134°C; 18 min | 57 | 4.11 |
| Rogez-Kreuz et al19 | 2009 | 263K scrapie strain | Stainless steel wires in 10% homogenate | Hamsters, implanted | Autoclaving, 134°C; 18 min | 50 | ≥5 to 6 |
| NaOH (1 N), room temperature, 1 h then autoclaving, 134°C: 18 min | 28 | ≥5 to 6 | |||||
| Enzymatic detergent (2%), 37°C; 10 min then autoclaving, 134°C; 18 min | 100 | 4.0 | |||||
| Alkaline detergent A (1%), 70°C; 10 min then autoclaving, 134°C; 18 min | 0 | ≥5 to 6 |
NOTE. BSE, bovine spongiform enchephalopathy; h, hours; IC, intracerebrally inoculated; LVG, Lakeview Golden; min, minutes.
a
Transmission rates are from hamsters injected with 10−1 dilution group.
b
Wires were placed on support during autoclaving at 134°C.
c
All infected mice did not display clinical signs and survived to the end of the experiment but were classified as infected after neuropathological examination.