During major public health incidents, health agencies and emergency services often need to reassure the public about the level of risk involved, advise them of measures that are being taken to safeguard public health, and specify what actions individuals can take to minimise their own risk. Learning lessons from any relevant events that occur in the real world is therefore vital.
So researchers at King's College London and the Health Protection Agency (HPA) assessed public perceptions of the risk to health and the impact of public health communications following the death of Alexander Litvinenko from radioactive polonium-210 in central London on 23 November 2006.
They carried out a telephone survey of a representative sample of adult Londoners during the incident. Interviews were also conducted with a sample of the public who had been in a contaminated area (a central London sushi restaurant and the bar of a London hotel).
One thousand people completed the telephone survey and 86 took part in the interviews. One hundred and seventeen (11.7%) of those surveyed perceived their health to be at risk. Factors associated with perceiving one's health to be at risk included being female, having a non white ethnic background, having a household income of under Ģ30,000 per year, and renting one's home.
Levels of knowledge about polonium-210 were generally low, with recognition of HPA messages ranging from 15% to 58%. The exception was the statement that "If you have not been in one of the areas known to be contaminated with polonium-210, then there is no risk to your health:" 71% of participants recognised that this was correct.
Participants who believed that the incident was related to terrorism or a public health threat were more likely to believe that their health was at risk than those who reported that it was related to espionage or was aimed at a single person.
Most (80%) also felt the HPA's response to the incident had been "appropriate or about right."
Interviewees were also generally satisfied with the information they received, though would have preferred more information about their individual risk of exposure, the results of their urine tests, and the health implications of the incident.
Despite involving radioactive contamination in the heart of a major city, these results show that the polonium incident caused limited public concern about potential health risks, say the authors.
This was partly due to the perception of the incident as a 'spy story' and partly due to successful communication about the restricted nature of any risk. Had the incident been portrayed as linked to terrorism, public concern might have been greater.
Care should be taken in future incidents to ensure that detailed, comprehensible and relevant information about the risks of exposure is made available to those who require it, they conclude.
This view is supported in an accompanying editorial that calls for improved crisis and emergency risk communication to be at the heart of future planning and training.
The research also continues to show that the general public is more resilient in the face of new threats than is sometimes anticipated.