Guidelines for second generation HIV surveillance - World Health ...

Contents
Acknowledgements
1. Introduction 3
1.1. What is second generation surveillance 3
1.2. Purpose of this document 4
1.3. Background 4
Ethical considerations 4
1.4. What this update includes 5
1.5. Process (→ “From start to finish: the process of HIV surveillance”) 5
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Evaluating a National Surveillance System
2. Where are the epidemic hotspots in your country 6
2.1. Prepare an inventory of existing information 6
2.1.1. Identify sources of data 6
2.1.2. Know your epidemic 7
2.1.3. Learn where most new infections come from in your country 7
2.1.4. Develop a surveillance inventory 7
2.2. Identify key populations at increased risk for HIV 8
2.2.1. Step 1: Decide which key populations are important to track 9
2.2.2. Step 2: Estimate the size of key populations, if relevant 13
2.2.3. Step 3: Assess the levels of risk intensity among key populations at increased risk 15
2.2.4. Step 4: Assess the current level of HIV prevalence 17
2.3. Create a national picture: map epidemiological zones 19
2.4. What are the gaps in your country’s surveillance activities 21
3. Design a comprehensive surveillance system 23
3.1 Develop a surveillance plan 24
3.1.1. Recommended surveillance activities by epidemic category 26
3.1.2. Collect data on a regular basis from a variety of sources 30
3.1.3. Track paediatric cases with advanced HIV infection 32
3.1.4. Understand mortality trends in surveillance 33
3.1.5. Review the design of your surveillance system regularly 33
3.2. Integrate the plan into existing health systems 34
3.2.1. Develop the infrastructure to support second generation surveillance 34
3.2.2. Strengthen laboratory systems 35
3.2.3. Provide technical support 36
3.2.4. Use external collaborators for surveillance activities 36
4. Use results to predict trends 38
4.1. What the biological trends indicate 38
4.1.1. Make use of your HIV prevalence data 38
4.1.2. Step 1: Understand the relationship between prevalence trends, incidence and mortality 39
4.1.3. Step 2: Assess selection bias in surveillance trend data 41
4.1.4. Step 3: Look for more evidence that supports a change in trends 44
4.1.5. Tools for deriving incidence from HIV prevalence data 44
4.2. What the behavioural trends indicate 47
4.2.1. Use behavioural data to know your epidemic 48
4.2.2. Bias in behavioural data 48
4.2.3. The role of integrated biological and behavioural surveys 49
4.2.4. Other sources of data 49
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