Hygiene is the maintenance of healthful practices. In modern terminology, this is usually regarded as a particular reference to cleanliness.
Outward signs of good hygiene include the absence of visible dirt (including dust and stains on clothing) or of bad smellss. Since the development of the germ theory of disease, hygiene has come to mean any practice leading to the absence of harmful levels of germs.
Good hygiene is an aid to health, beauty, comfort and social intercourse. Good hygiene directly aids in disease prevention and/or disease isolation. (That is, if you are healthy, good hygiene will help you avoid illness. If you are sick, good hygiene can reduce your contagiousness to others.)
Washing is the most common example of hygienic behavior. Washing is often done with soap or detergent which helps to remove oils and to break up dirt particles so they may be washed away.
Hygienic practices -- such as frequent hand washing or the use of boiled (and thus sterilized) water in medical operations -- have a profound impact on reducing the spread of disease. This is because they kill kill or remove disease-causing microbes (germs) in the immediate surroundings. For instance, washing one's hands after using the toilet and before handling food reduces the chance of spreading E. coli bacteria and hepatitis A, both of which are spread from fecal contamination of food.
In particular, the use of antibacterial soap in the home is of doubtful benefit and may actually be harmful. Antibacterial soaps contain a low concentration of a chemical to kill bacteria. These chemicals may be similar to ones used in fighting infection. Their use in everyday cleansers contribute to the evolution of resistance in common bacteria to these chemicals. This would make antibiotics far less useful in combating infections. There are also growing concerns that the overuse of antibacterial soaps create an environment where a growing child's immune system is understimulated, leaving them more susceptible to disease when they are older.
Commercial and cultural aspects
TV advertising campaigns in many countries have attempted to influence public opinion that only clean and sterile is healthy and safe. While the general advantages of hygienic behavior are undisputed, there are questions about the long-term benefits and dangers of an extreme position.Hygenic practices (an incomplete list)
See also: dry cleaning, vacuum cleaner, washing machine, five second rule
