Table 2.
Proportions of disease transmissions to hamsters after intracerebral inoculation of 0.03 ml of fresh or formalin-fixed scrapie-infected brain tissue, either unheated or exposed to dry heat at various times and temperatures
| Specimen | Undiluted | Log10
dilution
|
||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| −0.7 | −1 | −2 | −3 | −4 | −5 | −6 | −7 | −8 | −9 | −10 | ||
| Fresh tissue | ||||||||||||
| Unheated control | 4/4 | 7/7 | 12/12 | 11/11 | 10/12 | 0/12 | 0/8 | |||||
| Heated 5 min | ||||||||||||
| 150°C | 8/8 | 8/8 | 8/8 | 8/8 | ||||||||
| 300°C | 34/34 | 12/12 | 8/8 | |||||||||
| 600°C | 0/15 | |||||||||||
| 1,000°C | 0/17 | |||||||||||
| Heated 15 min | ||||||||||||
| 150°C | 8/8 | 8/8 | 8/8 | 8/8 | ||||||||
| 300°C | 33/33 | 12/12 | 7/8 | |||||||||
| 600°C | 5/18 | |||||||||||
| Formalin-fixed tissue | ||||||||||||
| Unheated control | 7/8 | 5/12 | 3/12 | 1/12 | 0/12 | 0/8 | ||||||
| Heated 5 min | ||||||||||||
| 150°C | 8/8 | 8/8 | 8/8 | 7/8 | ||||||||
| 300°C | 34/34 | 12/12 | 8/8 | |||||||||
| 600°C | 1/24 | |||||||||||