is for Epi

1. is for Epi Epidemiology basics for non-epidemiologists

2. Session IVPart I Surveillance

3. Session Overview • Introduction to Public Health Surveillance • Passive, active, and syndromic surveillance • Communicable disease law • Paper-based surveillance of reportable diseases • Applications and limitations • Federal Public Health Surveillance • CDC’s role • Data sources • Surveillance reporting examples

4. Session Overview (cont’d.) • Techniques for Review of Surveillance Data • Considerations when working with surveillance data • Access to data sources for rate numerators and denominators • Descriptive epidemiology • Graph and map surveillance rates

5. Today’s Learning Objectives • Recognize the applications and limitations of current public health surveillance practices • Understand the function of three different types of surveillance: active, passive, and syndromic • Be familiar with federal public health surveillance systems relevant to epidemiology programs • Understand the reciprocal pathway of data exchange through county, state, and federal surveillance efforts • Recognize the major components of surveillance data analysis

6. What is Surveillance?

7. What is Surveillance? CDC: The ongoing systematic collection, analysis, and interpretation of health data, essential to the planning, implementation, and evaluation of public health practice, closely integrated with the timely dissemination to those who need to know.

8. Standardized data collection County and state health departments and CDC who analyze data using statistical methods -Physicians -Laboratories -STD clinics -Community health clinics

9. Standardized data collection County and state health departments and CDC who analyze data using statistical methods -Physicians -Laboratories -STD clinics -Community health clinics Dissemination to those who need to know Dissemination to those who need to know -Public health officials -Health directors -Health policy officials

10. Standardized data collection County and state health departments and CDC who analyze data using statistical methods -Physicians -Laboratories -STD clinics -Community health clinics Dissemination to those who need to know Dissemination to those who need to know Change in public health practice (vaccination, reduction of risk factors, medical intervention, etc.) -Public health officials -Health directors -Health policy officials Public health planning and intervention

11. Standardized data collection County and state health departments and CDC who analyze data using statistical methods -Physicians -Laboratories -STD clinics -Community health clinics Dissemination to those who need to know Public health evaluation Dissemination to those who need to know Change in public health practice (vaccination, reduction of risk factors, medical intervention, etc.) -Public health officials -Health directors -Health policy officials Public health planning and intervention

12. NNDSS & NETSS • The National Notifiable Disease Surveillance System (NNDSS) • Disease-specific epidemiologic information • 60 nationally notifiable infectious diseases • 10 non-notifiable infectious diseases • The National Electronic Telecommunications System for Surveillance (NETSS)

13. Elements of Surveillance • Mortality reporting – legally required • Morbidity reporting – legally required • Epidemic reporting • Timely reporting • Laboratory investigations • Individual case investigations • Epidemic field investigations • Analysis of data

14. Types of Surveillance • Passive • Active • Syndromic

15. Passive Surveillance Laboratories, physicians, or other health care providers regularly report cases of disease to the local or state health department based on a standard case definition of that particular disease.

16. Communicable Disease Reporting:Passive Surveillance Lab Physician Hospital Public CDC Local Health Department State

17. Acquired Immunodeficiency Syndrome (AIDS)  Anthrax Arboviral neuroinvasive and non-neuroinvasive diseases Botulism Brucellosis Chancroid Chlamydia trachomatis, genital infections Cholera Coccidioidomycosis  Cryptosporidiosis Cyclosporiasis Diphtheria Ehrlichiosis Enterohemorrhagic Escherichia coli Giardiasis Gonorrhea Haemophilus influenzae, invasive disease Hansen disease (leprosy) Specific reportable diseases and conditions are mandated by state law, and may be different for every state. Recommended Reportable Diseases

18. Active Surveillance Local or state health departments initiate the collection of specific cases of disease from laboratories, physicians, or other health care providers.

19. Communicable Disease Reporting:Active Surveillance Lab Physician Hospital CDC Local Heath Department State

20. Active Surveillance Applications • Outbreak investigations • Other times when complete case ascertainment is desired (e.g., research study)

21. Syndromic Surveillance The ongoing, systematic collection, analysis, interpretation, and application of real-time indicators for disease that allow for detection before public health authorities would otherwise identify them.

22. What are “indicators of disease?” • “Indicators” • Clinical signs that we can categorize into syndromes • NOT a specific diagnosis! Example: Cough + Sore throat + Fatigue + Fever = Influenza-Like Illness

23. Common Syndromesunder Surveillance • Gastroenteritis • Influenza-like illness (ILI) • Meningitis / Encephalitis • Rash / Fever • Botulinic • Hemorrhagic

24. Why Do Syndromic Surveillance? • Early detection of clusters in naturally occurring outbreaks or a BT event • Minimizes mortality & morbidity • Characterize outbreak • Magnitude, rate of spread, effectiveness of control measures • Quick investigation • Detection of unexplained deaths

25. Limitations of Syndromic Surveillance • Inadequate specificity: false alarms • Uses resources in investigation • Inadequate sensitivity: failure to detect outbreaks/BT events • Outbreak is too small • Population disperses after exposure, cluster not evident

26. Limitations of Syndromic Surveillance • Costly • Staff expertise required • Formal evaluation of syndromic surveillance systems are incomplete

27. Surveillance Applications

28. Applications • Establish public health priorities • Aid in determining resource allocation • Assess public health programs • Facilitate research • Determine baseline level of disease • Early detection of epidemics • Estimate magnitude of the problem • Determine geographical distribution

29. Establish Public Health Priorities • Frequency • Incidence, prevalence, mortality, years of life lost • Severity • Case fatality rate, hospitalization, disability • Cost • Direct, indirect

30. Resource Allocation TUBERCULOSIS: Reported cases per 100,000 population, United States and U.S. territories, 2002 Source:http://www.cdc.gov/dphsi/annsum/index.htm

31. Assess Public Health Programs Gonorrhea: reported cases per 100,000 population, United States, 1987 - 2002 Data Graphed by Race and Ethnicity Data Graphed by Gender Source:http://www.cdc.gov/dphsi/annsum/index.htm

32. Determine Baseline Rates TUBERCULOSIS among U.S.-born and foreign-born persons, by year, United States, 1990-2002 *For 120 cases, origin of patients was unknown.

33. Early Detection of Epidemics Boston, MA

34. Surveillance Limitations

35. Limitations • Uneven application of information technology • Paper-based versus Electronic • Timeliness • Reporting time requirement • Reporting burden • Completeness • Unreported cases • Incomplete reports

36. Limitations: Multiple Categorical Systems Current Situation Program Specific Reports and Summaries MMWR Annual Summaries MMWR Weekly Tables Statistical Surveys for Chronic Diseases, Injuries and Other Public Health Problems STD*MIS TIMS NNDSS EIP Systems PHLIS HARS CDC Varied communications methods and security - specific to each system - including diskettes, e-mail, direct modem lines, etc. Reporting by Paper Form, Telephone & Fax Data Sources State Health Dept EIP Systems HARS STD*MIS TIMS NETSS PHLIS Physicians Varied communications methods and security - specific to each system- including paper forms, diskettes, e-mail, direct modem lines, etc. Chart Review Lab Reports HARS STD*MIS TIMS NETSS EIP Systems* PHLIS * EIP Systems (ABC, UD, Foodnet) City/County Health Department STD*MIS (Optional at the Clinic) TIMS (Optional at the Clinic)

37. National Electronic Disease Surveillance System (NEDSS) • NEDSS is not a surveillance system • Electronically integrates existing surveillance systems for easy data collection, storage and access • Security to meet confidentiality needs

38. Surveillance Challenges at the State Level • Quality of the data • Balancing priorities • Discrepancies and perspectives • Translating data into information

39. Quality of the Data • Completeness of case ascertainment • Completeness and accuracy of case information • Timeliness of reports • Sentinel indicators ‘Tip of the iceberg’

40. Discrepancies and Perspectives • Clinical vs surveillance case definitions • Cases ‘worked’ vs cases ‘counted’ • Place of exposure, residence, diagnosis • Re-infection or duplicate report • Stats by date of onset, diagnosis, report

41. Translating Data into Information • Provides the basis for public health action • Requires sound analysis and interpretation • Extracts meaningful, actionable findings • Requires clear presentation of complex issues