Introduction To and Overview Of Case Based Surveillance NASTAD Global Program

Overview  Discussion About: –Epidemiological Surveillance –Case-based Surveillance  Reasoning, benefit and added value  Requirements for system implementation –How Implementation Might Look  Case-based surveillance  Biological and behavioural surveillance

Epidemiological Surveillance

Surveillance  What is Surveillance? –Keeping a close watch over something  What is Epidemiological Surveillance? –The ongoing, systematic collection, analysis, and interpretation of health data essential to planning, implementing, and evaluating public health practice, closely integrated with the timely dissemination of these data to those who need to know

Why Do Epidemiological Surveillance?  To understand the disease in order to: –To prevent the disease –To protect the public’s health and wellness  To promote public health and a public health response by identifying: –Public health problems –Populations who are affected –Risk factors  Surveillance is essential for planning, implementation, and evaluation of public health practice

Methods Used for Epidemiological Surveillance  Population-based Surveys –A sample of a population is defined, sampled, and surveyed –With modeling, findings may be generalizable  Sentinel Site Surveillance –As above, but sampling occurs only at a set number of locations –Finding may be generalizable to some part of the population  Case-based Surveillance –A ‘census’ of all known/diagnosed cases of a disease

Methods of Surveillance: Population-based Demographic and Health Survey  National representative household survey –Population, Health, Nutrition  Sample size: –5,000 to 30,000 households  Regular frequency: – +/- 5 years, to allow comparisons over time  Random and representative sample of households selected –Household: All who normally sleep there (including staff), and guests who spent the previous night  60 minutes survey with all eligible: –Men age 15-59; Women age ; Info about children ages 0-5 Data available via

Types of Surveillance: Sentinel Surveillance  Sentinel (and Behavioral) Surveillance –Specific sites and population groups –Predetermined number of persons –Testing done in regular and consistent way (WHO)  Communicable diseases  Antenatal  Men who have sex with men  Injection drug users  Commercial sex workers  Truck drivers Data available via MoH’s, or otherwww.FHI.orgwww.DHS.org

Types of Surveillance: Case-based  Case-based Surveillance –Regular and systematic reporting of all cases –Stronger system if data come from many sources –A living system that is updated as cases are reported –Sensitive to outbreaks, changes in trends

Discussion  What methods of surveillance are in use in your country?  What are some pros and cons of each method of surveillance?  Do you see the data being used to guide: –Planning, implementation, evaluation? –Are data disseminated in a timely and routine fashion?

Why Case-Based Surveillance?

Evolution of Data Needs  Need or desire for—or possible access to—epidemiologic data in countries has evolved over the past 10 years  PEPFAR I (2004): Few national level HIV care and treatment programs –Surveillance need at that time was to monitor HIV (or AIDS) in general population to understand what was happening.  PEPFAR II (2009): Many national large scale prevention, care and treatment programs –People are living with HIV for many years; planners need epidemiologic information about people who are diagnosed with HIV to know how to best treat and best prevent HIV.  Today: There are usable data are everywhere –Program-driven M&E and patient tracking required this.

Benefits of HIV/AIDS Case Surveillance  Provides an ongoing and comprehensive understanding of a country’s epidemic –Who –Where –When –How  Allows for better allocation of resources –Prevention –Care and Treatment  Provides context for M&E information  Leverages existing information; ‘low’ resource needs

Why Case-Based Surveillance Data are available Use of data can improve a local and national response Case-based surveillance provides a framework

Basic Elements of Case-Based Surveillance

As Easy As… ABCDEF

HIV/AIDS Case Surveillance System: Basic Elements A.Define what you want to know –What do you want to be able to describe about HIV/AIDS? –What do you want to be able to describe about trends over time? –What do you want to be able to describe about the population?

HIV/AIDS Case Surveillance System: Basic Elements B.Define what needs to be reported to answer your questions –HIV infection (all stages) or –Advanced stage HIV disease (stages 3, 4) or –AIDS (stage 4)

Monitor HIV Disease HIV disease sentinel events HIV exposure (exposed infants or sexual transmission ) HIV infection 1 st positive HIV test 1 st CD4 count 1 st CD4 count <350 1 st viral load 1 st CD4 <200 AIDS-related Opportunistic Infection Death

Monitor HIV Disease HIV disease sentinel events HIV exposure (exposed infants or sexual transmission ) HIV infection 1 st positive HIV test 1 st CD4 count 1 st CD4 count <350 1 st viral load 1 st CD4 <200 AIDS-related Opportunistic Infection Death AIDS Case Reporting

Monitor HIV Disease HIV disease sentinel events HIV exposure (exposed infants or sexual transmission ) HIV infection 1 st positive HIV test 1 st CD4 count 1 st CD4 count <350 1 st viral load 1 st CD4 <200 AIDS-related Opportunistic Infection Death HIV Case Reporting

HIV/AIDS Case Surveillance System: Basic Elements C.Define which other events should be reported to help you answer what you want to know –1 st positive test  First event for a person… sets the clock –1 st CD4+ test  How long post diagnosis are CD4 tests done?  Do counts seem to be high or low? –1 st CD4+ < 200  What is the average time from HIV diagnosis to AIDS diagnosis?  How many people who are eligible for ART are on ART? –HIV exposure (children)  What happens to the babies exposed to HIV? –Death  What is the average time from HIV diagnosis to death?

HIV/AIDS Case Surveillance System: Basic Elements D.Define who must report –Public health facilities –Laboratories –Private health facilities –Other

Data Flow for Case Surveillance National (unduplicated dataset with all variables) Sub-national (all variables) Health facility (all variables) Health facility (all variables) Sub-national (all variables) Health facility (all variables) Health facility (all variables) Sub-national (all variables) Health facility (all variables) Health facility (all variables)

HIV/AIDS Case Surveillance System: Basic Elements E.Define how cases will be linked and cleaned –Name-based  John Adams  Jane Allen –Code-based  JA1268F F.Define how cases will be reported –Paper –Electronic –Where will cases be cleaned and de-duplicated –Where will cases be stored

Discussion In your country: A.Is there a need for this? B.Do you think there is/could be interest in this?

Discussion C.In your country, are there: –Local data collection systems? –Larger tracking or M&E systems?

Patient Registers

Patient Care Record

EMR

Discussion D.Are there any existing data pathways that could be used?

Discussion  What are some questions that can be answered via case-based surveillance? And the Public Health benefit –Do people test for HIV early or late in their infection?  Implications for increased HIV transmission and years lost of life; would look to have more ‘early testers’. –What is the average time between HIV diagnosis and AIDS diagnosis and/or death?  As above. Would look to increase the time between events. –What proportion of people who test positive for HIV enter into the treatment and care system?  How can the referral system be improved to capture all? –What proportion of people in the treatment and care system access regular and routine care?  Are national standards adhered to? Are other resources needed to support routine care? –What proportion of those eligible for ART have access?  Are the national standards adhered to? What can improve access?

Some Important Considerations

The Need for a Unique Case Identifier  Patient Identification –What it is  A unique way to identify each case (person) –Why it is important  Patient identification is important if we want to have a unique count of persons infected with HIV  Patient identification allows patient tracking over time  Each event is entered into the system to determine if it is a unique (new) record. Some will be new cases; some will be an update to an existing patient in the system. Updates include: –Transition from HIV to AIDS –A pregnancy –A visit to a different clinic system –A death

Selecting a Unique Case Identifier  The case identifier must: –Be unique to the individual –Not change over time or allow time of change to be known –Be easy to identify from a clinical record –Be something that is or is derived from routinely collected data  The case identifier must be able to: –Distinguish duplicate reports for the same person –Distinguish cases with the identifier who are different persons –Allow follow-up information from the surveillance program and healthcare provider to be easily connected with existing information

Discussion  In your country, is there something like a unique ID code in use?

Data Management and Cleaning  Data Deduplication –What it is  An evaluation and assessment of each case entered into the system to determine if it is a unique (new) case, or if it is an update on an existing patient in the system –Why it is important  Deduplication is important if we want to have a unique count of persons infected with HIV  Deduplication, and matching records to the source file, allows patient tracking over time

Data Management and Cleaning  Data Deduplication –How it can be done  Manually or automatically  Cases are matched by certain selected criteria: –Unique ID Code - Each record needs one for each patient  Ideally, people have national identifiers (and they are used!) before a record is entered  More often a unique identifier must be established from some combination of common demographic information  The more unique, the more certainty that records are for the same person –Combination of other variables that are somewhat unique:  NameParents Names  Date of BirthLocation of Birth  Location of Residence  Records that match are appended to each other to track over time

Data Management and Cleaning  Data Validation –What it is  A review of data to see that what is submitted is accurate  Examples: –Are the report dates more recent than the last data transfer? –Does everyone have a birthdate? –How many fields are completely empty? –Why it is important  Speaks to the quality of the data  People make mistakes. The wrong file can be uploaded, data can be deleted, or records can be shifted. –How it can be done  Chart review (sub-set) vs. submitted data  Record review (sub-set) vs. submitted data

A Central Management System Why?  De-duplication of cases between and among systems to provide a unique count of cases –Patient tracking within and between networks –Better trend monitoring –Additional data source to triangulate with existing prevalence estimates and/or program outputs  Greater controls for patient privacy and data confidentiality  Ownership of surveillance data buy government to enable leadership in public health functions

Discussion  In your country, is data management and data validation visible or available?

Putting the Pieces Together ~ an example from Haiti

Strategic Planning 1.What is the goal? –Stop mother to child transmission 2.What is needed to reach the goal? –Test all pregnant women –Provide treatment, care, outreach, support –Provide follow-up after birth for exposed children 3.What resources and systems exist? –Patient registers –Some reporting pathways –Case managers

Sample : Reporting the Spectrum of HIV/AIDS Morbidity and Mortality Pregnancy+ HIV+ Test Pre-Natal and Pediatric Surveillance Prophylaxis at Delivery 1 st ART (PMTCT Prophylaxis) Entry to PMTCT Prophylaxis Post- Delivery + while Nursing Infant Visit within 72 Hours Infant PCR Infant HIV Screen (6 months) Infant HIV Screen (18 months) Entry to ART/Care Entry to Care (if HIV+) Infant Prophylaxis after birth (AZT, NVP)

MESI Monitoring, Evaluation, and Surveillance Interface National EMR (I-TECH) Local EMRs VCT PMTCT PEPFAR Treatment and Care GHESKIO/PIH Treatment and Care HIV/AIDS Case Surveillance Centralized Database Epidemiologic Analyses Periodic Reports Quality Assurance Laboratory- Based Reporting

(MESI, Haiti, Daily/Weekly)- “Surveillance”-Online (MESI, Haiti, Daily/Weekly)- “Surveillance”-Offline (I-TECH, WA, Biweekly/Monthly)-EMR (GHESKIO, Haiti, Biweekly/Monthly)-EMR (PIH, MA, Biweekly/Monthly)-EMR HAITI HIV SURV MOH MESI ITECH MESI 1 De-duplication Surveillance Loop

Sample Roles and Responsibilities

Sample Data Collection Tool Proposed:  PMTCT Case ‘Flagged’ by case surveillance system  Site level staff contacted to arrange for follow-up  Sentinel event tool used to track woman pre- and post- natally  Cues for staff follow-up: –Tool –User interface –National data system

Summary

Case Based Surveillance  When devising or expanding a case-based surveillance system, priorities include: –Knowing what you want to know and –Tracking what you want to track  However, you might also consider: –Best use of existing resources where resources include: –Data systems, data variables, data flow, and data- personnel