Pre-amble: The promises and pitfalls of using assays for recent infection to estimate HIV incidence

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Pre-amble The promises and pitfalls of using
assays for recent infection to estimate HIV
incidence

• Denis Nash, PhD, MPH
• Associate Professor
• Epidemiology and Biostatistics Program
• Hunter College School of Public Health
• SED Core, HIV Center for Clinical and Behavioral
  Studies

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A prospective study of HIV incidence
HIV status unknown
Recruitment
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A prospective study of HIV incidence
Recruitment
HIV testing
HIV negative
HIV positive
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A prospective study of HIV incidence
Did not seroconvert
Recruitment
Seroconverted
HIV testing
Enrollment of HIV negatives
Prospective follow-up
HIV negative (study participants)
6 months
Baseline
Prospective follow-up
HIV positive (excluded)
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A prospective study of HIV incidence
Did not seroconvert
Recruitment
Seroconverted
HIV testing
Enrollment of HIV negatives
Incidence rate

Prospective follow-up
Person-time
Calculation of HIV incidence
6 months
Baseline
Prospective follow-up
HIV positive (excluded)
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A cross-sectional study of HIV incidence (STARHS)
HIV status unknown
Recruitment
6 months
Baseline
Retrospective follow-up
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A cross-sectional study of HIV incidence (STARHS)
Seroconverted in last 6 months
1. Identification of HIV-positive persons via
conventional HIV testing
2. Additional testing of HIV positives by
recent Infection assay
Seroconverted gt6 months ago
6 months
Baseline
Retrospective follow-up
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A cross-sectional study of HIV incidence (STARHS)
HIV-negative
Seroconverted in last 6 months
Incidence rate

Person-time
Calculation of HIV incidence
Seroconverted gt6 months ago
Excluded
6 months
Baseline
Retrospective follow-up
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Prospective study
STARHS (cross-sectional)
HIV-negative
Did not seroconvert
Seroconverted in last 6 months
Seroconverted

Incidence rate

Incidence rate
Person-time
Person-time
Seroconverted gt6 months ago (excluded)
Baseline
Baseline
6 months
6 months
Prospective follow-up
Prospective follow-up
HIV positive (excluded)