Public Health and Communicable Diseases - SA Health - SA.Gov.au

In the early 1800s Chadwick identified the appallingliving conditions of industrial England as causes of illhealth in workers, resulting in their inability to perform inthe workplace as well as they otherwise might. At thistime the miasma theory of disease was predominantand environment was ascribed the status of agent.With Koch’s discoveries from the mid-1870s, cameconcerted attention upon the diad of biological agentand host with less emphasis on the environment. Thusbegan an era where the emphasis of public health was(rightly) communicable disease. These are illnessesdue to specific infectious agents or their toxic productstransmitted from another infected host or from ananimate or inanimate reservoir.The recognition that an understanding of diseasedynamics could be usefully described by the triadhost-agent-environment arose in the 1920s withthe development of social and holistic medicine. Italso came to be the basis of training by AlexanderLangmuir and the Epidemic Intelligence Service and theconcept of ‘shoe leather epidemiology’ was promoted.Importantly, this required investigators to go into thefield to interview cases, their families, industry andother informants such as local health workers andgovernment officials.However, it was always necessary to view theenvironment as a multi-level construct ranging fromcellular interactions, to person to person interactions andto the influences at community and country level. Therehas been an evolving process of developing theory thateffectively integrates these multiple levels of factors thatcan all be viewed as causes of disease 1 .Classical epidemiology is being integrated with socialor cultural investigations as this theory evolves. This isimportant for several reasons. Firstly it reinforces theneed to fully understand the nature of a problem beforedesigning a solution and we see an increasing emphasison introducing ethnographic techniques into traditionalcommunicable disease investigations 2 . Secondly thisinvolves a mix of research methods – quantitative andqualitative to reach that understanding with betteranalytic methods to handle the data from mixed methodresearch becoming available. Finally, just as illness anddisease can be better understood with this paradigm, sotoo can appropriate means of intervention be devised.Clearly, the overwhelming message is that appropriateresources must be invested for adequate fieldinvestigations to secure reliable research findings whichcan be translated into feasible policy.References1. Kreiger N. Theories for social epidemiology in the 21 stcentury: an ecosocial perspective. Int. J Epidemiol.2001;30:668-677.2. Weiss MG. Cultural epidemiology: an introduction andoverview. Anthropology and Medicine 2001;8(1):5-29.Public Healthsurveillance forCommunicable Diseasesin South AustraliaIntroductionCameron MoffattEpidemiology Registrar,Communicable Disease Control BranchDepartment of HealthMaster of Applied Epidemiology ProgrammeAustralian National UniversityCommunicable disease control remains a high priorityfor population health. In Australia, many of the controlsfor communicable diseases already exist outside of thehealth system. These include things such as education,clean water, secure food sources, systems for disposalof refuse and sewage and adherence to regulationssuch as building codes. Disease surveillance helps toidentify cases when breakdowns in these systems mayhave occurred, however the pathogens responsible forthese diseases are frequently evolving, readily exploitingopportunities for change and transmission. In particularviruses transmitted in the air or by respiratory secretionshighlight the need for systems capable of detecting andmonitoring the presence of such pathogens.This paper examines public health surveillance with aparticular focus on notifiable conditions, using wherepossible relevant South Australian examples. Includedis an examination of effective public health surveillanceand its core aims; the main types of surveillancesystems used for monitoring communicable diseases;discussion of the importance of notifiable conditions;specific reporting systems and surveillance; the analysisand dissemination of surveillance data; and concludingremarks.What is public health surveillance?Public health surveillance is the systematic and on-goingassessment of the health of a community, including thetimely collection, analysis, interpretation, disseminationand subsequent use of that data. 1An effective public health surveillance system collectsrelevant data on a problem of public health importance,allowing users of the system to classify and interpretthat data to enable appropriate interventions to beapplied. All surveillance systems need to include thiscapacity for data collection and analysis as well astimely distribution of that data to those responsible forimplementing prevention and control measures.