Use of epidemiologic methods in disaster management Dr AA Abubakar Dept of Community Medicine Ahmadu Bello University Zaria Nigeria

Learning objectives Define disaster epidemiology Give historical overview of disaster epidemiology Discuss applications of epidemiologic methods to disasters ( before, during & after the events)

Epidemiology The study of the distribution & determinants of health related events in human populations and the application of the study to the control of health problems Host Agent Environment Epidemiologic triad

Study designs in epidemiology Observational study –Descriptive study: Description of the occurrence of a disease in a population Usually described in person, place & time –Analytical study: Analyses relationships between health status & other variables Case control study Cohort study Experimental study or intervention study

Disaster epidemiology Use of epidemiology in disaster situations Epidemiologic methods can be used to measure & describe the adverse effects of natural and man made disasters

Types of studies in disaster epidemiology Surveillance –Ongoing systematic collection, collation & analysis of data & the timely transmission of information to those who need to know for action to be taken Public Health impact evaluation Natural history evaluation Analytic studies of risk factors

Types of studies in disaster epidemiology 2 Clinical investigation Population based study Study of the psychological effects of disasters

Historical development of disaster epidemiology Early review of role of epidemiology during disasters Late 1960 Civil war in Nigeria: Practical application of epidemiology in disaster management Early 1970 Establishment of Center for Research on Epidemiology of Disasters

Historical development of disaster epidemiology Earthquake in Guatemala important epidemiologic studies carried out 1980 Eruption of Mount St Helena was a major milestone in shaping governments response to disasters

Before a disaster Conducting hazard & vulnerability analyses of the population –Hazard analysis: Collecting & assessing data on the nature, causes, frequency, distribution and effects of past events in order to make predictions about future events –Vulnerability analysis: analysis of a population risk when a hazard of a given magnitude occurs

Before a disaster 2 Modeling/ Simulating disaster scenarios Conducting drills Designing emergency protocols Assessing level of Emergency preparedness Assessing flexibility of surveillance systems Training health & safety personnel

During a disaster Conducting disaster damage assessment Conducting rapid field investigations Identifying urgent needs & matching resources Prioritizing relief efforts Conducting disaster surveillance Conducting epidemic investigations

After a disaster Conducting post disaster epidemiologic follow up studies Identifying risk factors for death & injury Planning strategies to reduce impact- related morbidity & mortality Developing specific interventions based on the nature of the disaster

After a disaster 2 Evaluating effectiveness of interventions Conducting descriptive & analytical studies Planning medical & public health responses to future disasters Conducting long term follow-up of rehabilitation & reconstruction activities

Challenges to applying epidemiologic methods Extent of physical destruction Public fear Social disruption Lack of infrastructure for data collection Time urgency for results Movement of populations Lack of local support or expertise

Challenges for selecting study designs Cross sectional: Studies of frequencies of deaths, illnesses, injuries and adverse health effects –Limited by absence of population counts Analytical study: Case control study is the best study to determine risk factors & study interactions among multiple factors –Limited by definition of specific outcomes & issues of selecting cases & controls

Conclusion Epidemiology can provide much needed information on which a rational, effective & flexible policy for the management of disaster is based Epidemiology provides the tools for rapid & effective problem solving during public health emergencies like natural & man made disasters

Questions?