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1.  HIV Diversity as a Biomarker for HIV Incidence Estimation: Including a High-Resolution Melting Diversity Assay in a Multiassay Algorithm 
Journal of Clinical Microbiology  2014;52(1):115-121.
Multiassay algorithms (MAAs) can be used to estimate cross-sectional HIV incidence. We previously identified a robust MAA that includes the BED capture enzyme immunoassay (BED-CEIA), the Bio-Rad Avidity assay, viral load, and CD4 cell count. In this report, we evaluated MAAs that include a high-resolution melting (HRM) diversity assay that does not require sequencing. HRM scores were determined for eight regions of the HIV genome (2 in gag, 1 in pol, and 5 in env). The MAAs that were evaluated included the BED-CEIA, the Bio-Rad Avidity assay, viral load, and the HRM diversity assay, using HRM scores from different regions and a range of region-specific HRM diversity assay cutoffs. The performance characteristics based on the proportion of samples that were classified as MAA positive by duration of infection were determined for each MAA, including the mean window period. The cross-sectional incidence estimates obtained using optimized MAAs were compared to longitudinal incidence estimates for three cohorts in the United States. The performance of the HRM-based MAA was nearly identical to that of the MAA that included CD4 cell count. The HRM-based MAA had a mean window period of 154 days and provided cross-sectional incidence estimates that were similar to those based on cohort follow-up. HIV diversity is a useful biomarker for estimating HIV incidence. MAAs that include the HRM diversity assay can provide accurate HIV incidence estimates using stored blood plasma or serum samples without a requirement for CD4 cell count data.
doi:10.1128/JCM.02040-13
PMCID: PMC3911463  PMID: 24153134
2.  Performance of a Limiting-Antigen Avidity Enzyme Immunoassay for Cross-Sectional Estimation of HIV Incidence in the United States 
PLoS ONE  2013;8(12):e82772.
Background
A limiting antigen avidity enzyme immunoassay (HIV-1 LAg-Avidity assay) was recently developed for cross-sectional HIV incidence estimation. We evaluated the performance of the LAg-Avidity assay alone and in multi-assay algorithms (MAAs) that included other biomarkers.
Methods and Findings
Performance of testing algorithms was evaluated using 2,282 samples from individuals in the United States collected 1 month to >8 years after HIV seroconversion. The capacity of selected testing algorithms to accurately estimate incidence was evaluated in three longitudinal cohorts. When used in a single-assay format, the LAg-Avidity assay classified some individuals infected >5 years as assay positive and failed to provide reliable incidence estimates in cohorts that included individuals with long-term infections. We evaluated >500,000 testing algorithms, that included the LAg-Avidity assay alone and MAAs with other biomarkers (BED capture immunoassay [BED-CEIA], BioRad-Avidity assay, HIV viral load, CD4 cell count), varying the assays and assay cutoffs. We identified an optimized 2-assay MAA that included the LAg-Avidity and BioRad-Avidity assays, and an optimized 4-assay MAA that included those assays, as well as HIV viral load and CD4 cell count. The two optimized MAAs classified all 845 samples from individuals infected >5 years as MAA negative and estimated incidence within a year of sample collection. These two MAAs produced incidence estimates that were consistent with those from longitudinal follow-up of cohorts. A comparison of the laboratory assay costs of the MAAs was also performed, and we found that the costs associated with the optimal two assay MAA were substantially less than with the four assay MAA.
Conclusions
The LAg-Avidity assay did not perform well in a single-assay format, regardless of the assay cutoff. MAAs that include the LAg-Avidity and BioRad-Avidity assays, with or without viral load and CD4 cell count, provide accurate incidence estimates.
doi:10.1371/journal.pone.0082772
PMCID: PMC3873916  PMID: 24386116
3.  Addressing HIV prevention research priorities in the United States 
More than half a million Americans became newly infected with HIV in the first decade of the new millennium. The domestic epidemic has had the heaviest impact on men who have sex with men (MSM) and people from racial and ethnic minority populations, particularly African-Americans. For example, Black MSM represent <1% of the U.S. population but 25% of the new HIV cases, as per CDC estimates published in 2008. While Black and Hispanic women constitute 24% of all U.S. women, they accounted for 82% of HIV cases in women in 2005, based on data from 33 states with confidential name-based reporting. There is a nearly 23-fold higher rate of AIDS diagnoses for Black women (45.5/100,000 women) and nearly 6-fold higher rate for Hispanic women (11.2/100,000) compared to the rate for white women (2.0/100,000). Investigators from the HIV Prevention Trials Network (HPTN), an NIH-sponsored collaborative clinical trials group, have crafted a domestic research agenda with community input. Two new domestic studies are in progress (2009) and a community-based clinical trial feasibility effort is in development (2010 start date). These studies focus on outreach, testing, and treatment of infected persons as a backbone for HIV prevention. Reaching persons not receiving health message and service with novel approaches to both prevention and care/treatment is an essential priority for HIV control in the U.S.; our research is designed to guide the best approaches and assess the impact of bridging treatment and prevention.
doi:10.1086/651485
PMCID: PMC2862583  PMID: 20397942
HIV; prevention; United States; homosexual; women; transmission; antiretroviral treatment; black; Hispanic

Results 1-3 (3)