Disinfection is the destructive action on pathogens due to a mechanism of chemical or physical exercised directly.
LEVELS OF DISINFECTION
Low-level disinfection: a process that eliminates most bacteria, some viruses and some fungi, but it is not capable of killing the tubercle bacilli or bacterial spores.
(reduction of 1-2 log. ie 10/100 times less the number of germs)
Mid-level disinfection: process able to inactivate Mycobacterium tuberculosis, vegetative bacterial forms, most of the viruses and fungi, but not bacterial spores.
(reduction of 3 log. ie 1.000 times less the number of germs)
High-level disinfection: process leading to the destruction of all microorganisms and certain spore forms.
(reduction of 4-5 log. ie 10.000/100.000 times less the number of germs)
Sterilization: elimination of all microbial forms, including spores.
(reduction of 6 log. ie 1.000.000 times less the number of germs)
Source: Antisepsi e disinfezione in ambito sanitario e socio-sanitario - Servizio Sanitario Regionale Emilia-Romagna