A county government risk manager is contacted by concerned employees that several employees in one of the county's buildings have the same type of cancer. The employees believe that the building environment is the cause of the cancers. The risk manager is concerned for the safety of the employees; what is the source of this Cancer Cluster?
The manager of a local restaurant received a sick call from one of the restaurant's bartenders. He states that his physician has taken him out of work for a few weeks; reportedly due to Hepatitis A. The manager is concerned about the possibility of an outbreak of hepatitis A related to consumption of food and drinks at his restaurant. Do we have the point source of a Foodborne Illness Outbreak that will sicken many of the restaurant patrons?
Clusters of disease occur frequently and they cause significant concern to the public. A cluster of health events is defined as an unusual aggregation, real or perceived, of health events that occurs within a group of people, in a geographic area, or over a period of time without regard to whether the number of cases is greater than expected. Most often, they are reported by employees or individuals expressing concern about apparently similar disease manifestations. The widespread sentiment is that environmental and/or occupational causes are responsible and must be investigated.
In contrast to a cluster as defined above, outbreaks of disease are the occurrence of more cases of disease than expected in a localized group of individuals within a specific period of time. Usually, the cases are presumed to have a common cause or to be related to one another in some way.
An individual who reports an apparent cluster wants assurance that the appropriate persons will be notified and that immediate action will be taken. The public wants answers. These societal concerns are placing greater and greater demands upon the scientific community, asking questions for which there are no answers, demanding answers to questions which defy scientifically valid studies. The process of investigating a reported cluster must be a systematic, integrated approach with respect to determining potential common causes and simultaneously maintaining open communication with the concerned community and/or stakeholders.
Once a cluster investigation is complete, the estimated degree of risk inherent in the situation should be communicated to the concerned community or stakeholders. The risk must be put in the proper context; in a sensitive, non-condescending manner through comparison with involuntary risks associated with more familiar scenarios; such as being struck by lightening or being in an automobile accident.
The risk perceived by community members does not necessarily parallel the estimates of risk that are produced by scientific assessments. An individual's perceived risk often includes many factors, such as:
Physicians are often the best risk communicators as they are qualified to address human health concerns. In this capacity, they must be aware of and responsive to the fact that an individual's perceived problem must be resolved responsibly and sympathetically in order to mitigate escalation of the situation. Such situations become an even bigger challenge when there is no underlying adverse health risk or cluster of disease present.