Millions of people around the world die from diseases like measles, cholera, malaria, TB, and more each year. These diseases spread in places where poverty, displacement, environmental factors and lack of health care infrastructure create conditions ripe for infection. During emergencies, these conditions can be exacerbated and make it much more difficult to contain outbreaks and stop their further spread.

A disease outbreak occurs when a number of cases of a particular infectious agent is in excess of what would normally be expected for a community, geographic area or season. Outbreaks may be limited to a single neighborhood or affect thousands across a country or continent.

Epidemiology is the discipline that identifies the cause of disease outbreaks and helps to manage their prevention and control. Descriptive epidemiology is one of the key aspects of the investigation of outbreaks and it uses standardized variables such as time, place and person to identify potential outbreak causes.

Outbreaks can be caused by many things including changes to human or animal behaviour, introduction of novel strains and the way that infectious agents are maintained in our environment. Almost always, humans and their behaviors play an important part in how quickly outbreaks develop, expand and are contained. Civil society groups should play a role in supporting the work of governments and taking preventive actions like regular hand washing, covering coughs and sneezes, and keeping sick people away from others. In addition, they should participate in public information and awareness activities.