Water heating by a domestic water heater. Two conflicting safety issues affect water heater temperature—the risk of scalding from excessively hot water greater than , and the risk of incubating bacteria colonies, particularly "Legionella", in water that is not hot enough to kill them. Both risks are potentially life-threatening and are balanced by setting the water heater's thermostat to . The European Guidelines for Control and Prevention of Travel Associated Legionnaires’ Disease recommend that hot water should be stored at and distributed so that a temperature of at least and preferably is achieved within one minute at points of use. If there
Sociality and disease transmission Sociality and disease transmission The effects of how social grouping strategies may reduce or increase the spread of disease is critical for the health of large groups of people. Places with large amounts of human interaction have a high risk for disease transmission. Social groups, community structures, and different cultures have different strategies and behaviors of reducing the spread of disease. Animals groups and humans that live in a place with high population density have an increased risk of disease prevalence. Some ways that large groups can help reduce the spread of disease is to have clean water supply and