This shows the population that has been affected by the emergency. The affected population is the key figure to be reported during a response, and will determine the type of response required. During the acute stages of an emergency these figures can be highly changeable and uncertain, but as the response continues the figures should stabilise and then hopefully decline. It is important to recognise the units of measurements used – i.e. individuals, families, households, etc., as these will determine the response. If family or household is used, then how many people make up a family? Likewise if household is used, how many people make up a household? The definition of ‘affected’ can be hard to define and will vary, but may include injured, displaced or those affected by the emergency and in need of some form of assistance (e.g. without shelter, food, water, etc).
Strategic and operational.
Situational.
As early as possible in the response, and should be updated routinely – particularly during the acute stages.
Everyone. Individual clusters and specialists will be interested in the affected numbers that relate to their specialist expertise (e.g. the water, sanitation and hygiene (WASH) cluster will be interested in the number of people without safe drinking water, the shelter cluster in the number of people with damaged or destroyed houses).
The affected population figure will determine the type of response required, and is also one of the triggers for a response in the first place.
Try to use individual people as the unit of measurement rather than households or families, as this will remove any uncertainty around how many make up a family or household.
Use round figures – you can’t have a fraction of a person.
National and local government
Ministry of Health
Local Emergency Management Agency (LEMA)
Office for the Coordination of Humanitarian Affairs (OCHA)
Humanitarian clusters
Humanitarian Data Exchange