1 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Chapter 24 Public Health Surveillance and Outbreak Investigation

2 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Objectives 1. Define public health surveillance. 2. Analyze types of surveillance systems. 3. Identify steps in planning, analyzing, interviewing, and evaluating surveillance. 4. Recognize sources of data used when investigating a disease/condition outbreak. 5. Relate the role of the nurse in surveillance and outbreak investigation to the national core competencies for public health nurses (PHNs).

3 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Disease Surveillance Definitions and Importance Use of Public Health Surveillance Purposes of Surveillance Collaboration Among Partners Nurse Competencies Data Sources for Surveillance

4 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Definitions  Disease surveillance  Event  Process data  Outcome data  Biological terrorism  Chemical terrorism

5 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Uses of Public Health Surveillance  Estimate the magnitude of a problem.  Determine geographic distribution of an illness or symptoms.  Portray the natural history of a disease.  Detect epidemics; define a problem.  Generate hypotheses; stimulate research.  Evaluate control measures.  Monitor changes in infectious agents.  Detect changes in health practices.  Facilitate planning.

6 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Purposes of Surveillance  Assess public health status  Define public health priorities  Plan public health programs  Evaluate interventions and programs  Stimulate research

7 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Collaboration Among Partners  Federal agencies  State and local public health agencies  Hospitals  Health care providers  Medical examiners  Veterinarians  Agriculture  Pharmaceutical agencies  Emergency management  Law enforcement agencies  911 systems  Ambulance services  Urgent care and emergency departments  Poison control centers  Nurse hotlines  School  Industry

8 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Nurse Competencies  Analytic assessment skills  Communication  Community dimensions of practice  Basic public health science skills  Leadership and systems thinking  Minnesota Model of Public Health Interventions

9 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Data Sources for Surveillance  Mortality data  Vital statistics reports  Morbidity data  Notifiable disease reports  Laboratory reports  Hospital discharge reports  Billing data  Outpatient health care data  Specialized disease registries  Injury surveillance systems  Environmental surveys  Sentinel surveillance systems

10 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Notifiable Diseases  National notifiable diseases  State notifiable diseases

11 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Case Definitions  Criteria for defining cases of different diseases are essential for having a uniform, standardized method of reporting and monitoring diseases.  Case definition provides understanding of the data that are being collected and reduces the likelihood that different criteria will be used for reporting similar cases of a disease. Suspected Probable Confirmed  Examples

12 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Types of Surveillance Systems Passive System Active System Sentinel System Special Systems

13 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Passive System  Case reports are sent to local health departments by health care providers (i.e., physicians, PHNs), or laboratory reports of disease occurrence are sent to the local health department.  Case reports are summarized and forwarded to the state health department, national government, or organizations responsible for monitoring the problem.  National Notifiable Disease Surveillance System (NNDSS)

14 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Active System  PHN, as an employee of the health department, may begin a search for cases through contacts with local health providers and health care agencies  Nurse names the disease/event and gathers data about existing cases to try to determine the magnitude of the problem (how widespread it is).

15 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Sentinel System  Trends in commonly occurring diseases or key health indicators are monitored  A disease/event may be the sentinel or a population may be the sentinel

16 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Special Systems  Developed for collecting particular types of data and may be a combination of active, passive, and/or sentinel systems  Examples:  PulseNet system  BioNet  Laboratory Response Network (LRN)  Syndronic surveillance systems (bioterrorism)  Enhanced Surveillance Project (ESP)

17 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. The Investigation Investigation Objectives Patterns of Occurrence When to Investigate Steps in an Investigation Displaying of Data

18 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Investigation Objectives  To control and prevent disease or death  To identify factors that contribute to the disease outbreak/event occurrence  To implement measures to prevent occurrences  Defining magnitude of a problem/event  Endemic, hyperendemic, sporadic, epidemic, outbreak, pandemic, holoendemic, outbreak detection

19 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Patterns of Occurrence  Common source  Point source  Mixed outbreak  Intermittent or continuous source  Propagated outbreak  Causal factors from epidemiologic triangle

20 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. When To Investigate  An unusual increase in disease incidence should be investigated.  Most outbreaks of disease occur naturally and/or are predictable.  Outbreaks that occur as result of purposeful introduction of agent to population (bioterrorism) may not have predictable pattern.

21 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Steps in an Investigation  Confirm the existence of an outbreak.  Verify the diagnosis/define a case.  Estimate the number of cases.  Orient the data collected to person, place, and time.  Develop and evaluate a hypothesis.  Institute control measures and communicate findings.

22 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Displaying of Data  Step in analysis that shows graphically what is happening  Reduces the assumptions made about the event and provides a means for describing the event using quantitative data  Help in stating your hypothesis or your best guess about what is happening

23 Copyright © 2012 by Mosby, an imprint of Elsevier Inc. Copyright © 2008 by Mosby, Inc., an affiliate of Elsevier Inc. Spatial Map