What term describes the method of using heat to kill all microorganisms except spores?

The method described by the term "thermal disinfection" utilizes heat to significantly reduce the number of microorganisms present, achieving a state where most pathogens are eliminated, although it does not ensure that all spores are killed. This process is effective in sanitizing instruments and surfaces, making it suitable for applications where a high level of cleanliness is required but complete sterilization is not necessary.

On the other hand, steam sterilization and moist heat sterilization both involve the use of steam to achieve a higher temperature and pressure that effectively destroys microorganisms, including spores. These methods are considered sterilization techniques, as they ensure the complete eradication of all microbial life, including resistant spores. Chemical disinfection relies on the application of chemical agents to eliminate harmful microorganisms and is not based on heat.

In summary, thermal disinfection effectively reduces microbial load but does not achieve the full sterility required to eliminate all types of microorganisms, particularly spores, making it distinct from the other methods of sterilization mentioned.