Risk communication aims to reduce both ‘hazard’ - the physical, structural and economic damage caused by an event - and ‘outrage’ - the level of emotion, concern, fear, anxiety or anger brought on by the event or threat. Effective risk communication aims to keep ‘outrage’ in proportion to ‘hazard’ so that people will have the appropriate level of concern to motivate them to act and mitigate the danger facing them.

People process information in a particular way during a crisis and this is the basis for risk communication principles. Under stress, people may not hear the information properly or cannot remember it. They may oversimplify what they have heard. They may hold onto current beliefs and find it difficult to do things differently - seeking evidence to confirm these beliefs rather than challenge them. 

The advice being given can seem counterintuitive, e.g. that homes - normally places of safety - are in fact places of potential danger due to the spread of disease or an impending hurricane. If people are to believe the advice, the person giving it must be trusted. People may follow the advice of someone known and trusted even if they have no expertise and provide inaccurate information. Communication must be simple, credible, timely and consistent; it may need to be repeated and come from multiple sources. Communication must be specific to the context and provide clear actions that are relatively easy to follow.

People experience a wide range of emotions in response to a crisis. Communicators should expect fear and anxiety, uncertainty, hopelessness and helplessness and understand how these emotions can affect communication. Sometimes a perceived threat can motivate people to act, but fear of the unknown can be debilitating and make some people react inappropriately, or not at all. Risk communication aims to stop people from feeling that nothing can be done to change the situation or to reduce the threat. If people feel they have no power to influence the situation they may withdraw mentally and physically; enabling them to participate in the response can help to reduce their fears and helplessness. 

Denial is also a common reaction to a crisis. It can occur because people lack information or because they have been deliberately targeted with disinformation. It can also occur when people feel overwhelmed by fear and powerless to counter a threat that is far outside their experience.

Contrary to popular belief people rarely act irrationally during a crisis. What can be erroneously described as ‘panic’ is an extreme ‘fight or flight’ reaction which is a normal and rational survival response to threats. Accusing people of panic and of being irrational is usually counterproductive; when unwanted behaviours do occur (such as ‘panic buying’) it is preferable to acknowledge why this is happening and redirect people to more helpful actions. Criticising people for particular behaviours (such as breaking lockdowns or curfews) can also help to reinforce those behaviours amongst others by setting up negative social norms. Ongoing communication with people to understand why they are engaging in unhelpful actions and what motivates them should be at the heart of effective risk communication.

The stigmatisation of certain people or groups is very common in disease outbreaks; some people may be the victims of violence. Stigma should be challenged and care must be taken to avoid using communications or images that reinforce it. Mistrust of those responding - both government and aid organisations - can also be an issue and the affected community must be consulted on how to try and address this.