Disinfection is defined as a procedure, the result of which is transient and that eliminates or kills microorganisms and/or deactivates undesirable viruses that are carried by inert contaminated environments. Such operations, which are carried out in accordance with defined objectives, relate solely to the microorganisms that are present at the time the procedure is carried out.

Disinfection is a generic term that refers to any antimicrobial measure (regardless of the level of the outcome attained), using a product that exhibits in-vitro properties that meet the criteria of a disinfectant or antiseptic agent. The name of each disinfection procedure should indicate its application domain, for example, medical device disinfection, floor disinfection, and hand disinfection.

Sanitation refers to the provision of facilities and services for the safe management of human excreta from the toilet to containment and storage and treatment onsite or conveyance, treatment and eventual safe end use or disposal. More broadly sanitation also included the safe management of solid waste and animal waste. Inadequate sanitation is a major cause of infectious diseases such as cholera, typhoid and dysentery world-wide. It also contributes to stunting and impaired cognitive function and impacts on well-being through school attendance, anxiety and safety with lifelong consequences, especially for women and girls. Improving sanitation in households, health facilities and schools underpins progress on a wide range of health and economic development issues including universal health coverage and combatting antimicrobial resistance.

Disinfection is defined broadly as the destruction of microorganisms, except bacterial spores, on inanimate objects (e.g., medical devices such as endoscopes). Three levels of disinfection are achievable depending on the amount and kind of microbial killing involved. These levels of disinfection are as follows:

1.High-level disinfection (HLD): the destruction of all viruses, vegetative bacteria, fungi, mycobacterium, and some, but not all, bacterial spores.32,33 For LCGs, HLD is operationally defined as the ability to kill 106 mycobacteria (a six-log reduction). The efficacy of HLD is dependent on several factors and includes the type and level of microbial contamination; effective precleaning of the endoscope; presence of biofilm; physical properties of the object; concentration, temperature, pH, and exposure time to the germicide; and drying after rinsing to avoid diluting the disinfectant.32

2. Intermediate-level disinfection: the destruction of all mycobacteria, vegetative bacteria, fungal spores, and some nonlipid viruses, but not bacterial spores.

3. Low-level disinfection: a process that can kill most bacteria (except mycobacteria or bacterial spores), most viruses (except some nonlipid viruses), and some fungi.