Short Communication: Defining optimality of a test for recent infection for HIV incidence surveillance.

The estimation of HIV incidence from cross-sectional surveys using tests for recent infection has attracted much interest. It is increasingly recognized that the lack of high performance recent infection tests is hindering the implementation of this surveillance approach. With growing funding opportunities, test developers are currently trying to fill this gap.

A new general biomarker-based incidence estimator.

Background: Estimating disease incidence from cross-sectional surveys, using biomarkers for "recent" infection, has attracted much interest. Despite widespread applications to HIV, there is currently no consensus on the correct handling of biomarker results classifying persons as "recently" infected long after the infections occurred.

Methods: We derive a general expression for a weighted average of recent incidence that-unlike previous estimators-requires no particular assumption about recent infection biomarker dynamics or about the demographic and epidemiologic context.

Seroconverting blood donors as a resource for characterising and optimising recent infection testing algorithms for incidence estimation.

Introduction: Biomarker-based cross-sectional incidence estimation requires a Recent Infection Testing Algorithm (RITA) with an adequately large mean recency duration, to achieve reasonable survey counts, and a low false-recent rate, to minimise exposure to further bias and imprecision. Estimating these characteristics requires specimens from individuals with well-known seroconversion dates or confirmed long-standing infection. Specimens with well-known seroconversion dates are typically rare and precious, presenting a bottleneck in the development of RITAs.

HIV incidence estimation using the BED capture enzyme immunoassay: systematic review and sensitivity analysis.

Background: HIV incidence estimates are essential for understanding the evolution of the HIV epidemic and the impact of interventions. Tests for recent HIV infection allow incidence estimation based on a single cross-sectional survey. The BED IgG-Capture Enzyme Immunoassay (BED assay) is a commercially available and widely used test for recent HIV infection.

Using tests for recent infection to estimate incidence: problems and prospects for HIV.

Tests for recent infection (TRIs), such as the BED assay, provide a convenient way to estimate HIV incidence rates from cross-sectional survey data. Controversy has arisen over how the imperfect performance of a TRI should be characterised and taken into account. Recent theoretical work is providing a unified framework within which to work with a variety of TRI- and epidemic-specific assumptions in order to estimate incidence using imperfect TRIs, but suggests that larger survey sample sizes will be required than previously thought.