- 7.2.1: Controlling Microbial Growth
- Inanimate items, such as doorknobs, toys, or towels, which may harbor microbes and aid in disease transmission, are called fomites. Two factors heavily influence the level of cleanliness required for a particular fomite and, hence, the protocol chosen to achieve this level. The first factor is the application for which the item will be used and the second factor is the level of resistance to antimicrobial treatment by potential pathogens.
- 7.2.2: Using Physical Methods to Control Microorganisms
- For thousands of years, humans have used various physical methods of microbial control for food preservation. Common control methods include the application of high temperatures, radiation, filtration, and desiccation (drying), among others. Many of these methods nonspecifically kill cells by disrupting membranes, changing membrane permeability, or damaging proteins and nucleic acids by denaturation, degradation, or chemical modification.
- 7.2.3: Using Chemicals to Control Microorganisms
- In addition to physical methods of microbial control, chemicals are also used to control microbial growth. A wide variety of chemicals can be used as disinfectants or antiseptics. This section describes the variety of chemicals used as disinfectants and antiseptics, including their mechanisms of action and common uses.
Thumbnail: Scanning electron microscope image of Vibrio cholerae bacteria, which infect the digestive system. (Public Domain; T.J. Kirn, M.J. Lafferty, C.M.P Sandoe and R.K. Taylor).