What's the minimum temperature that will kill all pathogens?

Here in NZ recently, surgery was performed on a patient with CJD. The surgical instruments were sterilised in an autoclave, but to my surprise, the hospital announced that there was a small chance that patients later operated on with them could become infected. An autoclave is like a pressure cooker, reaching temperatures well above 100 Celsius. How hot would it need to be to reduce to zero the chance of any viruses or bacteria surviving?

The ones that we use are validated at 121-122 degrees celsius. The hospital is correct that there is a certain degree of resistance to heat that bacterial populations can exibit. But above that mark, nothing, not even endospores should be alive. That's why time is so important. Heat penetration into the items being autoclaved is one factor to consider. I'd double check the sterilization records for use of the standard B. stearothermophilus for valid operation.

One pathogen called strain 121 survives temperatures of 121C and 250F. These temperatures are considered to be adequate autoclave temps and most pathogens are killed. Prions (proteins) can be killed at 137C. I can only speculate as to how hot it would have to be to kill strain 121.

Don't be so surprised. Yes there a small chance that the instruments could cause infection. There's also a small chance that you'll die under anesthesia. There's even a chance you could be hit by a bus if you step outside your front door. There are no guarantees in life.