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Accurate methods for estimating HIV incidence from cross-sectional samples would have great utility in prevention research. This report describes recent improvements in cross-sectional methods that significantly improve their accuracy. These improvements are based on the use of multiple biomarkers to identify recent HIV infections. These multiassay algorithms (MAAs) use assays in a hierarchical approach for testing that minimizes the effort and cost of incidence estimation. These MAAs do not require mathematical adjustments for accurate estimation of the incidence rates in study populations in the year before sample collection. MAAs provide a practical, accurate, and cost-effective approach for cross-sectional HIV incidence estimation that can be used for HIV prevention research and global epidemic monitoring. [ABSTRACT FROM AUTHOR]

The article presents a study conducted in Uganda on frequency of long-term nonprogressors (LTNP) and HIV viruses' controllers in HIV-1 seroconverters. It states that LTNP is 7 years infected of T-cell count over 600 cells per liter and HIV viruses' controllers have undetectable viral loads on cases without antiretroviral treatment. It notes that the higher frequency of LTNPs in Uganda must be considered in making researches of viral pathogenesis and doing HIV virus vaccine trials in Africa.

The article discusses a study which examines the effect of viral suppression on cross-sectional HIV incidence testing in the Johns Hopkins Hospital Emergency Department in Baltimore, Maryland. HIV-positive patients were tested by the Vironostika-less sensitive enzyme immunoassay. The study found that viral suppression affects the performance of the cross-sectional incidence tests, which rely on antibody titer.

Examines the molecular epidemiology of HIV-1 subtypes in southern China. Prevalence of two distinct HIV epidemics in the country; Statistical variations between cities and HIV serostatus; Characteristics of the epidemic.

Objective: To characterize prevalence, incidence, and associated correlates of HIV infection among MSM in 12 cities across India., Design: Cross-sectional sample using respondent-driven sampling from September 2012 to June 2013., Methods: A total 12022 MSM (~1000/city) were recruited. Participants had to be at least 18 years, self-identify as male, and report oral/anal intercourse with a man in the prior year. HIV infection was diagnosed using three rapid tests. Cross-sectional HIV incidence was estimated using a multiassay algorithm. All estimates incorporate respondent-driven sampling-II weights., Results: Median age was 25 years, 45% self-identified as 'panthi' (predominantly penetrative anal intercourse) and 30.6% reported being married to a woman. Weighted HIV prevalence was 7.0% (range: 1.7-13.1%). In multivariate analysis, significantly higher odds of HIV infection was observed among those who were older, had lower educational attainment, were practicing purely receptive anal sex or both receptive and penetrative sex, and those who were herpes simplex virus-2 positive. Of 1147 MSM who tested HIV positive, 53 were identified as recent HIV infections (annualized incidence = 0.87%; range = 0-2.2%). In multivariate analysis, injecting drugs in the prior 6 months, syphilis, and higher number of male partners and fewer female partners were significantly associated with recent HIV infection., Conclusion: We observed a high burden of HIV among MSM in India with tremendous diversity in prevalence, incidence, and risk behaviors. In particular, we observed high incidence in areas with relatively low prevalence suggesting emerging epidemics in areas not previously recognized to have high HIV burden.

Objective: We previously developed a multiassay algorithm (MAA) to identify recent HIV infection that includes the BED-capture enzyme immunoassay, an avidity assay based on the Genetic Systems HIV-1/HIV-2 + O enzyme immunoassay, CD4 cell count, and HIV viral load. We used this MAA to evaluate the association between recent maternal HIV infection and in-utero transmission of HIV., Methods: Plasma samples were collected at delivery from 2561 HIV-infected women in the postexposure prophylaxis of infants-Malawi trial. The MAA described above was used to identify women with recent HIV infection. Logistic regression models assessed association between recent HIV infection and in-utero HIV transmission (defined as a positive infant HIV DNA test at birth)., Results: Seventy-three women were identified as recently infected using the MAA. Those women were younger and had lower parity than women who were identified as not recently infected using the MAA (P < 0.0001 for age and parity). The frequency of in-utero HIV transmission was 17.8% among women identified as recently infected, compared with 6.7% among women identified as not recently infected (13/73 vs. 166/2488, P = 0.001). In a multivariate model, three factors were independently associated with in-utero HIV transmission: recent infection [adjusted odds ratio (AOR): 2.49, 95% confidence interval (CI): 1.30-4.78, P = 0.006], log(10) HIV viral load at delivery (AOR: 2.01, 95% CI: 1.60-2.51, P < 0.0001), and younger age (per 10 year increase, AOR: 0.66, 95% CI: 0.43-0.93, P = 0.02)., Conclusion: Results obtained using a MAA suggest that recent maternal HIV acquisition is strongly associated with in-utero HIV transmission, independent of HIV viral load at delivery.

Objective: To assess the association between hormonal contraceptive use and HIV progression., Design: A retrospective analysis of 625 female HIV seroconverters from a Ugandan cohort study., Methods: Multivariate Cox regression analyses incorporating time-varying hormonal contraceptive exposure were used to estimate the adjusted hazard ratios of death, and a composite outcome of AIDS or death, associated with hormonal contraceptive use. Sensitivity analyses included lagging hormonal contraceptive exposure, varying comparison groups, and separately assessing effects of oral and injectable contraceptives., Results: A total of 27.5% of women reported ever using hormonal contraception. Of 625 women, 104 (16.6%) died and 291 (46.6%) progressed to AIDS or death during observation. Time-varying hormonal contraceptive use was not associated with an increased hazard of death as compared with nonuse of hormonal contraception (adjusted hazard ratio 0.76, 95% confidence interval 0.41-1.39, P = 0.37), and was associated with a significantly reduced hazard of progression to AIDS or death (adjusted hazard ratio 0.70, 95% confidence interval 0.50-0.97, P = 0.03). None of the sensitivity analyses suggested an adverse effect of hormonal contraception on HIV progression., Conclusion: Hormonal contraceptive use was not associated with faster progression to death, and was associated with a reduced hazard of progression to the composite outcome of AIDS or death.

Objective: To determine whether heterosexual transmission of HIV differs according to HIV-1 subtype., Design: A retrospective observational cohort., Methods: HIV-1 subtype effects on heterosexual HIV-1 transmission were determined among 268 HIV-discordant couples retrospectively identified from a population cohort in Rakai, Uganda. HIV-1 subtype (gag and gp41 sequencing and multiregion hybridization assay) and viral loads (reverse transcriptase PCR) were determined. Adjusted incidence rate ratios (adj IRR) of HIV transmission by subtype were estimated by multivariable Poisson regression adjusting for characteristics of index HIV-positive and HIV-negative partners., Results: Adjusting for index HIV-positive partners' age, viral load, stage of disease, genital ulcer disease, and HIV-negative partners' genital ulcer disease and nonuse of condoms, subtype A viruses were associated with a higher rate of transmission than subtype D [adj.IRR 1.98, 95% confidence interval (CI) 1.17-3.34], but no differences in transmission were observed between recombinant viruses and subtype D (aIRR 1.53, P = 0.25). Index-positive partners' age less than 30 years (adj.IRR 3.44, 95% CI 1.75-6.78) and viral load (adj.IRR 2.37, 95% CI 1.75-3.21), and index-negative partners' genital ulcer disease (adj.IRR 1.71, 95% CI 1.08-2.70) and nonuse of condoms (adj.IRR 1.94, 95% CI 1.15-3.28) were significant determinants of HIV transmission., Conclusion: In Rakai, Uganda, subtype A viruses have a significantly higher rate of heterosexual transmission than subtype D viruses. Differential subtype transmission efficiency may be important for HIV vaccine evaluation and could contribute to subtype-specific HIV epidemics in sub-Saharan Africa.

Design: We sought to investigate the evolutionary and historical reasons for the different epidemiological patterns of HIV-1 in the early epidemic. In order to characterize the demographic history of HIV-1 subtypes A and D in east Africa, we examined molecular epidemiology, geographical and historical data., Methodology: We employed high-resolution phylodynamics to investigate the introduction of HIV-1A and D into east Africa, the geographic trends of viral spread, and the demographic growth of each subtype. We also used geographic information system data to investigate human migration trends, population growth, and human mobility., Results: HIV-1A and D were introduced into east Africa after 1950 and spread exponentially during the 1970s, concurrent with eastward expansion. Spatiotemporal data failed to explain the establishment and spread of HIV based on urban population growth and migration. The low prevalence of the virus in the Democratic Republic of Congo before and after the emergence of the pandemic was, however, consistent with regional accessibility data, highlighting the difficulty in travel between major population centers in central Africa. In contrast, the strong interconnectivity between population centers across the east African region since colonial times has likely fostered the rapid growth of the epidemic in this locale., Conclusion: This study illustrates how phylodynamic analysis of pathogens informed by geospatial data can provide a more holistic and evidence-based interpretation of past epidemics. We advocate that this 'landscape phylodynamics' approach has the potential to provide a framework both to understand epidemics' spread and to design optimal intervention strategies., (2009 Wolters Kluwer Health | Lippincott Williams & Wilkins)

Objective: To analyze antiretroviral drug susceptibility in HIV from recently infected adults in Rakai, Uganda, prior to the availability of antiretroviral drug treatment., Methods: Samples obtained at the time of HIV seroconversion (1998-2003) were analyzed using the GeneSeq HIV and PhenoSense HIV assays (Monogram Biosciences, Inc., South San Francisco, California, USA)., Results: Test results were obtained for 104 samples (subtypes: 26A, 1C, 66D, 9A/D, 1C/D, 1 intersubtype recombinant). Mutations used for genotypic surveillance of transmitted antiretroviral drug resistance were identified in six samples: three had nucleoside reverse transcriptase inhibitor (NRTI) surveillance mutations (two had M41L, one had K219R), and three had protease inhibitor surveillance mutations (I47V, F53L, N88D); none had nonnucleoside reverse transcriptase inhibitor (NNRTI) surveillance mutations. Other resistance-associated mutations were identified in some samples. However, none of the samples had a sufficient number of mutations to predict reduced antiretroviral drug susceptibility. Ten (9.6%) of the samples had reduced phenotypic susceptibility to at least one drug (one had partial susceptibility to didanosine, one had nevirapine resistance, and eight had resistance or partial susceptibility to at least one protease inhibitor). Fifty-three (51%) of the samples had hypersusceptibility to at least one drug (seven had zidovudine hypersusceptibility, 28 had NNRTI hypersusceptibility, 34 had protease inhibitor hypersusceptibility). Delavirdine hypersusceptibility was more frequent in subtype A than D. In subtype D, efavirenz hypersusceptibility was associated with substitutions at codon 11 in HIV-reverse transcriptase., Conclusion: Phenotyping detected reduced antiretroviral drug susceptibility and hypersusceptibility in HIV from some antiretroviral-naive Ugandan adults that was not predicted by genotyping. Phenotyping may complement genotyping for analysis of antiretroviral drug susceptibility in populations with nonsubtype B HIV infection.

Objective: To estimate the survival time from HIV infection to death., Methods: A community cohort in Rakai district, Uganda, identified 837 seroconverters followed annually between 1995 and 2003 until they died, were censored by outmigration or truncated on 31 December 2003 because antiretroviral treatment became available. HIV-1 subtype was determined by multiple hybridization assay for 396 seroconverters. The median interval from infection to death was estimated by Kaplan-Meier survival analyses and Weibull models. Hazard ratios (HR) and their 95% confidence intervals (CI) associated with survival were estimated using Cox proportional hazards modeling, Results: There were 122 deaths over 2330 person-years (py), an average mortality of 5.2/100 py. The median survival time was 8.7 years (95% CI 8.1-9.3), and did not differ by sex, place of residence or time period of seroconversion. Survival time decreased significantly with older age at infection (P = 0.01). Survival was shorter with subtypes D, AD recombinant or multiple infections compared with subtype A (log rank P = 0.04), but this was of borderline significance after adjustment (adjusted HR 3.47, 95% CI 0.89-15.44, P = 0.07). Non-A subtypes constituted 84.6% of all identifiable infections and had a median survival time of 7.5 years (95% CI 6.4-8.5), whereas over 90% of those infected with subtype A were still alive 7 years post-infection., Conclusion: The median survival time in Rakai was shorter than reported in other African populations, and we hypothesize that this may be a result of the predominance of non-A subtypes with faster disease progression in this population.

Objective: To evaluate adherence, treatment interruptions, and outcomes in patients purchasing antiretroviral fixed-dose combination (FDC) therapy., Design: Ninety-seven participants were recruited into a prospective 24-week observational cohort study of HIV-positive, antiretroviral-naive individuals initiating self-pay Triomune or Maxivir therapy in Kampala, Uganda. Adherence was measured by monthly structured interview, unannounced home pill count, and electronic medication monitors (EMM). Treatment interruptions were measured as continuous intervals greater than 48 h without opening the EMM. The primary outcomes were survival with viral suppression below 400 copies/ml, CD4 cell increases, and genotypic drug resistance at 24 weeks., Results: The median baseline CD4 cell count was 56 cells/microl and median log10 copies RNA/ml was 5.54; mean adherence ranged from 82 to 95% for all measures but declined significantly over time. In an intent-to-treat analysis, 70 (72%) patients had an undetectable plasma HIV-RNA level at week 24. Sixty-two of 95 (65%) individuals with continuous EMM data had a treatment interruption of greater than 48 h. Treatment interruptions accounted for 90% of missed doses. None of 33 participants who did not interrupt treatment for over 48 h had drug resistance, whereas eight of 62 (13%) participants who did interrupt therapy experienced drug resistance. Antiretroviral resistance was seen in 8% of individuals and overall mortality was 10% at 24 weeks., Conclusion: HIV-positive individuals purchasing generic FDC antiretroviral therapy have high rates of adherence and viral suppression, low rates of antiretroviral resistance, and robust CD4 cell responses. Adherence is an important predictor of survival with full viral suppression. Treatment interruptions are an important predictor of drug resistance.