Just what is the risk?

Swine flu, avian flu and SARS – It seems that infectious disease is rarely far from a headline – but are we too quick to panic?

When it comes to new outbreaks of infectious disease effective risk communication is vital - but one group of scientists think that the risk of outbreaks can be amplified by an over eager media.

With the current outbreak of swine flu, and in the absence of a vaccine at present, the only way to contain the virus is to get people around the world to take precautionary measures say a group of Scandinavian researchers - but getting that message across is a fine balance.  

Writing in the Journal of Behavioral Medicine, Johannes Brug, Arja Aro, and Jan Hendrik Richardus say: “Risk communication messages that are not comprehended by the public at risk, or communication of conflicting risk messages will result in lack of precautionary actions, as will communications from a non-trustworthy source. However, risk communication messages are sometimes very quickly adopted by the media, possibly leading to an ‘amplification' of risk information that may lead to unnecessary mass scares and unnecessary or ineffective precautionary action.”

Ideally, say the team, implementation of precautionary measures needs effective risk communication that leads to the realistic perceptions of those risks, as well as knowledge and skills to promote precautionary practices. Looking at how risk is communicated - they show that - in the early stages of a possible pandemic, risk perceptions and people's confidence in recommended protective actions depend on effective communications.

The researchers show that there are three key parameters that convince people to take precautions. Firstly, they need to be aware of the risk to them. Secondly, they need to believe that effective protective actions are available and have confidence in them. Lastly, communications about risk need to be carefully managed so that they express the actual risk accurately to prevent mass scares.

But of course it isn’t just the media who have the potential to over blow the risks - there are many medical and public health institutions tasked with disseminating information to the population. 

So in the recent outbreak of swine flu - did they get it right?

One swine flu study led by Professor Neil Ferguson of the MRC Centre for Outbreak Analysis and Modelling at Imperial College London concludes that the Health Organisation's decision to raise the global pandemic alert to level 5 was indeed the right one.

Professor Ferguson and colleagues analysed the Mexican outbreak using early data on international spread and viral and genetic diversity to make an early assessment of the swine flu virus’ severity and potential to spread. The study has found that transmissibility is higher than that of seasonal flu.