Brief Report: Self-Reported HIV-Positive Status but Subsequent HIV-Negative Test Results in Population-Based HIV Impact Assessment Survey Participants-11 Sub-Saharan African Countries, 2015-2018

BACKGROUND

HIV testing is a critical step to accessing antiretroviral therapy (ART) because early diagnosis can facilitate earlier initiation of ART. This study presents aggregated data of individuals who self-reported being HIV-positive but subsequently tested HIV-negative during nationally representative Population-Based HIV Impact Assessment surveys conducted in 11 countries from 2015 to 2018.

METHOD

Survey participants aged 15 years or older were interviewed by trained personnel using a standard questionnaire to determine HIV testing history and self-reported HIV status. Home-based HIV testing and counseling using rapid diagnostic tests with return of results were performed by survey staff according to the respective national HIV testing services algorithms on venous blood samples. Laboratory-based confirmatory HIV testing for all participants identified as HIV-positives and self-reported positives, irrespective of HIV testing results, was conducted and included Geenius HIV-1/2 and DNA polymerase chain reaction if Geenius was negative or indeterminate.

RESULTS

Of the 16,630 participants who self-reported as HIV-positive, 16,432 (98.6%) were confirmed as HIV-positive and 198 (1.4%) were HIV-negative by subsequent laboratory-based testing. Participants who self-reported as HIV-positive but tested HIV-negative were significantly younger than 30 years, less likely to have received ART, and less likely to have received a CD4 test compared with participants who self-reported as HIV-positive with laboratory-confirmed infection.

CONCLUSIONS

A small proportion of self-reported HIV-positive individuals could not be confirmed as positive, which could be due to initial misdiagnosis, deliberate wrong self-report, or misunderstanding of the questionnaire. As universal ART access is expanding, it is increasingly important to ensure quality of HIV testing and confirmation of HIV diagnosis before ART initiation.

Age-disparate and intergenerational sex partnerships and HIV: the role of gender norms among adolescent girls and young women in Malawi

BACKGROUND

Age-mixing (age-disparate [5-9 years difference] and intergenerational [≥ 10 years difference]) partnerships are hypothesized drivers of HIV in adolescent girls and young women (AGYW; 15-24 years). These partnerships are often associated with increased gender inequities which undermine women's agency and assertiveness. We assessed whether age-mixing partnerships were associated with HIV in Malawi and if endorsement of inequitable gender norms modifies this relationship.

METHODS

We analyzed data from the Malawi Population-based HIV Impact Assessment, a nationally representative household survey conducted in 2015-2016. Participants underwent HIV testing and completed questionnaires related to actively endorsed gender norms and sexual risk behavior. We used multivariate logistic regression and multiplicative interaction to assess associations among AGYW who reported the age of their primary sex partner from the last year.

RESULTS

The analysis included 1,958 AGYW (mean age = 19.9 years, SD = 0.1), 459 (23.4%) and 131 (6.7%) of whom reported age-disparate and intergenerational partnerships, respectively. AGYW in age-mixing partnerships accounted for 13% of all AGYW and were older, more likely to reside in urban areas, to be married or cohabitating with a partner, and to have engaged in riskier sexual behavior compared with AGYW in age-concordant partnerships (p < 0.05). HIV prevalence among AGYW in age-disparate and intergenerational partnerships was 6.1% and 11.9%, respectively, compared with 3.2% in age-concordant partnerships (p < 0.001). After adjusting for residence, age, education, employment, wealth quintile, and ever been married or cohabitated as married, AGYW in age-disparate and intergenerational partnerships had 1.9 (95% CI: 1.1-3.5) and 3.4 (95% CI: 1.6-7.2) greater odds of HIV, respectively, compared with AGYW in age-concordant partnerships. Among the 614 (31% of the study group) who endorsed inequitable gender norms, AGYW in age-disparate and intergenerational partnerships had 3.5 (95% CI: 1.1-11.8) and 6.4 (95% CI: 1.5-27.8) greater odds of HIV, respectively, compared with AGYW in age-concordant partnerships.

CONCLUSIONS

In this Malawi general population survey, age-mixing partnerships were associated with increased odds of HIV among AGYW. These findings highlight inequitable gender norms as a potential focus for HIV prevention and could inform interventions targeting structural, cultural, and social constraints of this key group.

HIV incidence and prevalence among adults aged 15-64 years in Rwanda: Results from the Rwanda Population-based HIV Impact Assessment (RPHIA) and District-level Modeling, 2019

OBJECTIVES

The 2018-2019 Rwanda Population-based HIV Impact Assessment (RPHIA) was conducted to measure national HIV incidence and prevalence. District-level estimates were modeled to inform resources allocation.

METHODS

RPHIA was a nationally representative cross-sectional household survey. Consenting adults were interviewed and tested for HIV using the national diagnostic algorithm followed by laboratory-based confirmation of HIV status and testing for viral load (VL), limiting antigen (LAg) avidity, and presence of antiretrovirals. Incidence was calculated using normalized optical density ≤ 1·5, VL ≥ 1,000 copies/mL, and undetectable antiretrovirals. Survey and programmatic data were used to model district-level HIV incidence and prevalence.

RESULTS

Of 31,028 eligible adults, 98·7% participated in RPHIA and 934 tested HIV positive. HIV prevalence among adults in Rwanda was 3·0% (95% CI:2·7-3·3). National HIV incidence was 0·08% (95% CI:0·02-0·14) and 0·11% (95% CI:0·00-0·26) in the City of Kigali (CoK). Based on district-level modeling, HIV incidence was greatest in the 3 CoK districts (0·11% to 0·15%) and varied across other districts (0·03% to 0·10%).

CONCLUSIONS

HIV prevalence among adults in Rwanda is 3.0%; HIV incidence is low at 0.08%. District-level modeling has identified disproportionately affected urban hotspots: areas to focus resources.

Prevalence of and factors associated with late diagnosis of HIV in Malawi, Zambia, and Zimbabwe: Results from population-based nationally representative surveys

INTRODUCTION

Late diagnosis of HIV (LD) increases the risk of morbidity, mortality, and HIV transmission. We used nationally representative data from population-based HIV impact assessment (PHIA) surveys in Malawi, Zambia, and Zimbabwe (2015-2016) to characterize adults at risk of LD and to examine associations between LD and presumed HIV transmission to cohabiting sexual partners.

METHODS

We estimated the prevalence of LD, defined as CD4 count <350 cells/μL, among adults newly diagnosed with HIV during the surveys and odds ratios for associated factors. We linked newly diagnosed adults (index cases) to their household sexual partners and calculated adjusted odds ratios for associations between LD of the index case, viral load of the index case, and duration of HIV exposure in the relationship, and the HIV status of the household sexual partner.

RESULTS

Of 1,804 adults who were newly diagnosed with HIV in the surveys, 49% (882) were diagnosed late. LD was associated with male sex, older age, and almost five times the odds of having an HIV-positive household sexual partner (adjusted odds ratio [aOR], 4.65 [95% confidence interval: 2.56-8.45]). Longer duration of HIV exposure in a relationship and higher viral load of the index case were both independently associated with higher odds of having HIV-positive household sexual partners. Individuals with HIV exposure of more than 5 years had more than three times (aOR 3.42 [95% CI: 1.63-7.18]) higher odds of being HIV positive than those with less than 2 years HIV exposure. The odds of being HIV positive were increased in individuals who were in a relationship with an index case with a viral load of 400-3499 copies/mL (aOR 4.06 [95% CI 0.45-36.46]), 3,500-9,999 copies/mL (aOR 11.32 [95% CI: 4.08-31.39]), 10,000-49,999 copies/mL (aOR 17.07 [95% CI: 9.18-31.72]), and ≥50,000 copies/mL (aOR 28.41 [95% CI: 12.18-66.28]) compared to individuals who were in a relationship with an index case with a viral load of <400 copies/mL.

CONCLUSIONS

LD remains a challenge in Southern Africa and is strongly associated with presumed HIV transmission to household sexual partners. Our study underscores the need for earlier HIV diagnosis, particularly among men and older adults, and the importance of index testing.

Population Viral Load, Viremia, and Recent HIV-1 Infections: Findings From Population-Based HIV Impact Assessments (PHIAs) in Zimbabwe, Malawi, and Zambia

BACKGROUND

HIV population viral load (PVL) can reflect antiretroviral therapy program effectiveness and transmission potential in a community. Using nationally representative data from household surveys conducted in Zimbabwe, Malawi, and Zambia in 2015-16, we examined the association between various VL measures and the probability of at least one recent HIV-1 infection in the community.

METHODS

We used limiting-antigen avidity enzyme immunoassay, viral load suppression (VLS) (HIV RNA <1000 copies/mL), and antiretrovirals in the blood to identify recent HIV-1 cases.

RESULTS

Among 1510 enumeration areas (EAs) across the 3 surveys, 52,036 adults aged 15-59 years resided in 1363 (90.3%) EAs with at least one HIV-positive adult consenting to interview and blood draw and whose VL was tested. Mean HIV prevalence across these EAs was 13.1% [95% confidence intervals (CI) 12.7 to 13.5]. Mean VLS prevalence across these EAs was 58.7% (95% CI: 57.3 to 60.0). In multivariable analysis, PVL was associated with a recent HIV-1 case in that EA (adjusted odds ratio: 1.4, 95% CI: 1.2 to 1.6, P = 0.001). VLS prevalence was inversely correlated with recent infections (adjusted odds ratio: 0.3, 95% CI: 0.1 to 0.6, P = 0.004). The 90-90-90 indicators, namely, the prevalence of HIV diagnosis, antiretroviral therapy coverage, and VLS at the EA level, were inversely correlated with HIV recency at the EA level.

CONCLUSIONS

We found a strong association between PVL and VLS prevalence and recent HIV-1 infection at the EA level across 3 southern African countries with generalized HIV epidemics. These results suggest that population-based measures of VLS in communities may serve as a proxy for epidemic control.

A randomized double-blind controlled trial of convalescent plasma in adults with severe COVID-19

BACKGROUNDAlthough convalescent plasma has been widely used to treat severe coronavirus disease 2019 (COVID-19), data from randomized controlled trials that support its efficacy are limited.METHODSWe conducted a randomized, double-blind, controlled trial among adults hospitalized with severe and critical COVID-19 at 5 sites in New York City (USA) and Rio de Janeiro (Brazil). Patients were randomized 2:1 to receive a single transfusion of either convalescent plasma or normal control plasma. The primary outcome was clinical status at 28 days following randomization, measured using an ordinal scale and analyzed using a proportional odds model in the intention-to-treat population.RESULTSOf 223 participants enrolled, 150 were randomized to receive convalescent plasma and 73 to receive normal control plasma. At 28 days, no significant improvement in the clinical scale was observed in participants randomized to convalescent plasma (OR 1.50, 95% confidence interval [CI] 0.83-2.68, P = 0.180). However, 28-day mortality was significantly lower in participants randomized to convalescent plasma versus control plasma (19/150 [12.6%] versus 18/73 [24.6%], OR 0.44, 95% CI 0.22-0.91, P = 0.034). The median titer of anti-SARS-CoV-2 neutralizing antibody in infused convalescent plasma units was 1:160 (IQR 1:80-1:320). In a subset of nasopharyngeal swab samples from Brazil that underwent genomic sequencing, no evidence of neutralization-escape mutants was detected.CONCLUSIONIn adults hospitalized with severe COVID-19, use of convalescent plasma was not associated with significant improvement in day 28 clinical status. However, convalescent plasma was associated with significantly improved survival. A possible explanation is that survivors remained hospitalized at their baseline clinical status.TRIAL REGISTRATIONClinicalTrials.gov, NCT04359810.FUNDINGAmazon Foundation, Skoll Foundation.

Prevalence of nonsuppressed viral load and associated factors among HIV-positive adults receiving antiretroviral therapy in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe (2015 to 2017): results from population-based nationally representative surveys

INTRODUCTION

The global target for 2020 is that ≥90% of people living with HIV (PLHIV) receiving antiretroviral therapy (ART) will achieve viral load suppression (VLS). We examined VLS and its determinants among adults receiving ART for at least four months.

METHODS

We analysed data from the population-based HIV impact assessment (PHIA) surveys in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe (2015 to 2017). PHIA surveys are nationally representative, cross-sectional household surveys. Data collection included structured interviews, home-based HIV testing and laboratory testing. Blood samples from PLHIV were analysed for HIV RNA, CD4 counts and recent exposure to antiretroviral drugs (ARVs). We calculated representative estimates for the prevalence of VLS (viral load <1000 copies/mL), nonsuppressed viral load (NVL; viral load ≥1000 copies/mL), virologic failure (VF; ARVs present and viral load ≥1000 copies/mL), interrupted ART (ARVs absent and viral load ≥1000 copies/mL) and rates of switching to second-line ART (protease inhibitors present) among PLHIV aged 15 to 59 years who participated in the PHIA surveys in Eswatini, Lesotho, Malawi, Zambia and Zimbabwe, initiated ART at least four months before the survey and were receiving ART at the time of the survey (according to self-report or ARV testing). We calculated odds ratios and incidence rate ratios for factors associated with NVL, VF, interrupted ART, and switching to second-line ART.

RESULTS

We included 9200 adults receiving ART of whom 88.8% had VLS and 11.2% had NVL including 8.2% who experienced VF and 3.0% who interrupted ART. Younger age, male sex, less education, suboptimal adherence, receiving nevirapine, HIV non-disclosure, never having married and residing in Zimbabwe, Lesotho or Zambia were associated with higher odds of NVL. Among people with NVL, marriage, female sex, shorter ART duration, higher CD4 count and alcohol use were associated with lower odds for VF and higher odds for interrupted ART. Many people with VF (44.8%) had CD4 counts <200 cells/µL, but few (0.31% per year) switched to second-line ART.

CONCLUSIONS

Countries are approaching global VLS targets for adults. Treatment support, in particular for younger adults, and people with higher CD4 counts, and switching of people to protease inhibitor- or integrase inhibitor-based regimens may further reduce NVL prevalence.

Mapping male circumcision for HIV prevention efforts in sub-Saharan Africa

BACKGROUND

HIV remains the largest cause of disease burden among men and women of reproductive age in sub-Saharan Africa. Voluntary medical male circumcision (VMMC) reduces the risk of female-to-male transmission of HIV by 50-60%. The World Health Organization (WHO) and Joint United Nations Programme on HIV/AIDS (UNAIDS) identified 14 priority countries for VMMC campaigns and set a coverage goal of 80% for men ages 15-49. From 2008 to 2017, over 18 million VMMCs were reported in priority countries. Nonetheless, relatively little is known about local variation in male circumcision (MC) prevalence.

METHODS

We analyzed geo-located MC prevalence data from 109 household surveys using a Bayesian geostatistical modeling framework to estimate adult MC prevalence and the number of circumcised and uncircumcised men aged 15-49 in 38 countries in sub-Saharan Africa at a 5 × 5-km resolution and among first administrative level (typically provinces or states) and second administrative level (typically districts or counties) units.

RESULTS

We found striking within-country and between-country variation in MC prevalence; most (12 of 14) priority countries had more than a twofold difference between their first administrative level units with the highest and lowest estimated prevalence in 2017. Although estimated national MC prevalence increased in all priority countries with the onset of VMMC campaigns, seven priority countries contained both subnational areas where estimated MC prevalence increased and areas where estimated MC prevalence decreased after the initiation of VMMC campaigns. In 2017, only three priority countries (Ethiopia, Kenya, and Tanzania) were likely to have reached the MC coverage target of 80% at the national level, and no priority country was likely to have reached this goal in all subnational areas.

CONCLUSIONS

Despite MC prevalence increases in all priority countries since the onset of VMMC campaigns in 2008, MC prevalence remains below the 80% coverage target in most subnational areas and is highly variable. These mapped results provide an actionable tool for understanding local needs and informing VMMC interventions for maximum impact in the continued effort towards ending the HIV epidemic in sub-Saharan Africa.

Mapping HIV prevalence in sub-Saharan Africa between 2000 and 2017

HIV/AIDS is a leading cause of disease burden in sub-Saharan Africa. Existing evidence has demonstrated that there is substantial local variation in the prevalence of HIV; however, subnational variation has not been investigated at a high spatial resolution across the continent. Here we explore within-country variation at a 5 × 5-km resolution in sub-Saharan Africa by estimating the prevalence of HIV among adults (aged 15–49 years) and the corresponding number of people living with HIV from 2000 to 2017. Our analysis reveals substantial within-country variation in the prevalence of HIV throughout sub-Saharan Africa and local differences in both the direction and rate of change in HIV prevalence between 2000 and 2017, highlighting the degree to which important local differences are masked when examining trends at the country level. These fine-scale estimates of HIV prevalence across space and time provide an important tool for precisely targeting the interventions that are necessary to bringing HIV infections under control in sub-Saharan Africa.

Fine-scale estimates of the prevalence of HIV in adults across sub-Saharan Africa reveal substantial within-country variation and local differences in both the direction and rate of change in the prevalence of HIV between 2000 and 2017.

Changing Antiretroviral Eligibility Criteria: Impact on the Number and Proportion of Adults Requiring Treatment in Swaziland

OBJECTIVE

Early initiation of antiretroviral treatment (ART) at CD4 cell count ≥ 500 cells per microliter reduces morbidity and mortality in HIV-infected adults. We determined the proportion of HIV-infected people with high viral load (VL) for whom transmission prevention would be an additional benefit of early treatment.

DESIGN

A randomly selected subset of a nationally representative sample of HIV-infected adults in Swaziland in 2012.

METHODS

Eight to 12 months after a national survey to determine adult HIV prevalence, 1067 of 5802 individuals identified as HIV-infected were asked to participate in a follow-up cross-sectional assessment. CD4 cell enumeration, VL measurements, and ART status were obtained to estimate the proportion of currently untreated adults and of the entire HIV-infected population with high VL (≥ 1000 copies/mL) whose treatment under a test-and-treat or VL threshold eligibility strategy would reduce HIV transmission.

RESULTS

Of the 927 (87% of 1067) participants enrolled, 466 (50%) reported no ART use. Among them, 424 (91%) had VL ≥ 1000 copies per milliliter; of these, 148 (35%) were eligible for ART at the then existing CD4 count threshold of <350 cells per microliter; an additional 107 (25%) were eligible with expanded CD4 criterion of <500 cells per microliter; and 169 (40%) remained ART ineligible. Thus, 36% of the 466 currently untreated and 18% of the total 927 had high VL yet remained ART ineligible under a CD4 criterion of <500 cells per microliter.

CONCLUSIONS

A test-and-treat or VL threshold for treatment eligibility is necessary to maximize the HIV transmission prevention benefits of ART.

A smartphone dongle for diagnosis of infectious diseases at the point of care

This work demonstrates that a full laboratory-quality immunoassay can be run on a smartphone accessory. This low-cost dongle replicates all mechanical, optical, and electronic functions of a laboratory-based enzyme-linked immunosorbent assay (ELISA) without requiring any stored energy; all necessary power is drawn from a smartphone. Rwandan health care workers used the dongle to test whole blood obtained via fingerprick from 96 patients enrolling into care at prevention of mother-to-child transmission clinics or voluntary counseling and testing centers. The dongle performed a triplexed immunoassay not currently available in a single test format: HIV antibody, treponemal-specific antibody for syphilis, and nontreponemal antibody for active syphilis infection. In a blinded experiment, health care workers obtained diagnostic results in 15 min from our triplex test that rivaled the gold standard of laboratory-based HIV ELISA and rapid plasma reagin (a screening test for syphilis), with sensitivity of 92 to 100% and specificity of 79 to 100%, consistent with needs of current clinical algorithms. Patient preference for the dongle was 97% compared to laboratory-based tests, with most pointing to the convenience of obtaining quick results with a single fingerprick. This work suggests that coupling microfluidics with recent advances in consumer electronics can make certain laboratory-based diagnostics accessible to almost any population with access to smartphones.

A comparison of two measures of HIV diversity in multi-assay algorithms for HIV incidence estimation

BACKGROUND

Multi-assay algorithms (MAAs) can be used to estimate HIV incidence in cross-sectional surveys. We compared the performance of two MAAs that use HIV diversity as one of four biomarkers for analysis of HIV incidence.

METHODS

Both MAAs included two serologic assays (LAg-Avidity assay and BioRad-Avidity assay), HIV viral load, and an HIV diversity assay. HIV diversity was quantified using either a high resolution melting (HRM) diversity assay that does not require HIV sequencing (HRM score for a 239 base pair env region) or sequence ambiguity (the percentage of ambiguous bases in a 1,302 base pair pol region). Samples were classified as MAA positive (likely from individuals with recent HIV infection) if they met the criteria for all of the assays in the MAA. The following performance characteristics were assessed: (1) the proportion of samples classified as MAA positive as a function of duration of infection, (2) the mean window period, (3) the shadow (the time period before sample collection that is being assessed by the MAA), and (4) the accuracy of cross-sectional incidence estimates for three cohort studies.

RESULTS

The proportion of samples classified as MAA positive as a function of duration of infection was nearly identical for the two MAAs. The mean window period was 141 days for the HRM-based MAA and 131 days for the sequence ambiguity-based MAA. The shadows for both MAAs were <1 year. Both MAAs provided cross-sectional HIV incidence estimates that were very similar to longitudinal incidence estimates based on HIV seroconversion.

CONCLUSIONS

MAAs that include the LAg-Avidity assay, the BioRad-Avidity assay, HIV viral load, and HIV diversity can provide accurate HIV incidence estimates. Sequence ambiguity measures obtained using a commercially-available HIV genotyping system can be used as an alternative to HRM scores in MAAs for cross-sectional HIV incidence estimation.

Performance of a limiting-antigen avidity enzyme immunoassay for cross-sectional estimation of HIV incidence in the United States

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.

Mobile device for disease diagnosis and data tracking in resource-limited settings

BACKGROUND

Collection of epidemiological data and care of patients are hampered by lack of access to laboratory diagnostic equipment and patients' health records in resource-limited settings. We engineered a low-cost mobile device that combines cell-phone and satellite communication technologies with fluid miniaturization techniques for performing all essential ELISA functions.

METHODS

We assessed the device's ability to perform HIV serodiagnostic testing in Rwanda and synchronize results in real time with electronic health records. We tested serum, plasma, and whole blood samples collected in Rwanda and on a commercially available sample panel made of mixed antibody titers.

RESULTS

HIV testing on 167 Rwandan patients evaluated for HIV, viral hepatitis, and sexually transmitted infections yielded diagnostic sensitivity and specificity of 100% and 99%, respectively. Testing on 40 Rwandan whole-blood samples-using 1 μL of sample per patient-resulted in diagnostic sensitivity and specificity of 100% and 100%. The mobile device also successfully transmitted all whole-blood test results from a Rwandan clinic to a medical records database stored on the cloud. For all samples in the commercial panel, the device produced results in agreement with a leading ELISA test, including detection of weakly positive samples that were missed by existing rapid tests. The device operated autonomously with minimal user input, produced each result 10 times faster than benchtop ELISA, and consumed as little power as a mobile phone.

CONCLUSIONS

A low-cost mobile device can perform a blood-based HIV serodiagnostic test with laboratory-level accuracy and real-time synchronization of patient health record data.

Microfluidics-based diagnostics of infectious diseases in the developing world

One of the great challenges in science and engineering today is to develop technologies to improve the health of people in the poorest regions of the world. Here we integrated new procedures for manufacturing, fluid handling and signal detection in microfluidics into a single, easy-to-use point-of-care (POC) assay that faithfully replicates all steps of ELISA, at a lower total material cost. We performed this 'mChip' assay in Rwanda on hundreds of locally collected human samples. The chip had excellent performance in the diagnosis of HIV using only 1 μl of unprocessed whole blood and an ability to simultaneously diagnose HIV and syphilis with sensitivities and specificities that rival those of reference benchtop assays. Unlike most current rapid tests, the mChip test does not require user interpretation of the signal. Overall, we demonstrate an integrated strategy for miniaturizing complex laboratory assays using microfluidics and nanoparticles to enable POC diagnostics and early detection of infectious diseases in remote settings.

Addressing research priorities for prevention of HIV infection in the United States

More than half a million Americans became newly infected with human immunodeficiency virus (HIV) in the first decade of the new millennium. The domestic epidemic has had the heaviest impact on men who have sex with men and persons from racial and ethnic minority populations, particularly black persons. For example, black men who have sex with men represent <1% of the US population but 25% of new HIV infections, according to Centers for Disease Control and Prevention estimates published in 2008. Although black and Hispanic women constitute 24% of all US women, they accounted for 82% of HIV infections among women in 2005, according to data from 33 states with confidential name-based reporting. There is a nearly 23-fold higher rate of AIDS diagnoses among black women (45.5 diagnoses per 100,000 women) and a nearly 6-fold higher rate among Hispanic women (11.2 diagnoses per 100,000 women), compared with the rate among white women (2.0 diagnoses per 100,000 women). Investigators from the HIV Prevention Trials Network, a National Institutes of Health-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 prevention of HIV infection. Reaching persons not receiving health messages and services with novel approaches to both prevention and treatment is an essential priority for control of HIV infection in the United States; our research is designed to guide the best approaches and assess the impact of bridging treatment and prevention.

Screening HIV-infected patients for non-AIDS-defining malignancies

The use of antiretroviral therapy has reduced mortality and shifted the spectrum of malignancies affecting people living with HIV/AIDS (PLWH). We review guidelines and evidence for screening PLWH for non-AIDS-defining malignancies as compared with the general population. Cervical cancer screening clearly differs for HIV-seropositive women, with two Pap tests 6 months apart in the first year and then annually if normal. The role of cervical human papillomavirus screening has not yet been defined in HIV-seropositive women. Anal cancer screening consists of an annual digital rectal examination, and some (but not all) guidelines also recommend annual anal Pap tests. Screening for breast and colorectal cancer should follow standard, age-appropriate screening recommendations that apply to the general population. Screening HIV-infected men for prostate cancer, as with the general population, lacks a clear benefit. Despite increasing rates of hepatocellular carcinoma and lung cancers among PLWH, there is insufficient evidence to support routine screening.

Longitudinal anthropometric patterns among HIV-infected and HIV-uninfected women

INTRODUCTION

Previous studies suggest that indicators of central adiposity such as waist-to-hip ratio (WHR) and waist circumference may be altered by HIV infection, antiretroviral treatment, or both.

METHODS

Waist and hip circumference and body mass index (BMI) were measured among participants of the Women's Interagency HIV Study semiannually from 1999 to 2004. Generalized linear models evaluated longitudinal patterns of these measures and associations with demographic and clinical characteristics.

RESULTS

WHR was significantly larger, whereas BMI and waist and hip circumference were significantly smaller at almost all 11 semiannual visits among 942 HIV-infected women compared with 266 HIV-uninfected women. Among HIV-uninfected women, mean waist and hip circumference and BMI increased over the 5-year study period (waist: +4.1 cm or 4.4%, hip: +3.76 cm or 3.5%, and BMI +2.43 kg/m2 or 8.2%), whereas WHR remained stable. Among the HIV-infected women, waist and hip circumference, BMI, and WHR did not significantly change. Independent predictors of smaller BMI among HIV-infected women included white race, hepatitis C virus seropositivity, current smoking, higher viral load, and lower CD4 cell count. Independent predictors of larger WHR among HIV-infected women included age, white and other non-African American race, higher CD4 cell count, and protease inhibitor (PI) use. Use of a highly active antiretroviral therapy (HAART) regimen was not an independent predictor of BMI or WHR.

CONCLUSIONS

HIV-infected women had higher WHRs compared with HIV-uninfected women, despite lower BMIs and waist and hip measurements. BMI and waist and hip circumference increased over 5 years among the HIV-uninfected women but remained stable in the HIV-infected women. Among HIV-infected women, PI use was associated with a larger WHR, although HAART use itself was not appreciably associated with BMI or WHR.

Antiretroviral therapy exposure and incidence of diabetes mellitus in the Women's Interagency HIV Study

OBJECTIVE

To determine the incidence of diabetes mellitus (DM) in a nationally representative cohort of HIV-infected women and a comparison group of HIV-uninfected women.

DESIGN

A prospective study between October 2000 and March 2006 of 2088 participants from the Women's Interagency HIV Study who did not have evidence of DM at enrollment (1524 HIV infected and 564 HIV uninfected).

METHODS

Incident DM was defined as either having fasting glucose > or = 1.26 g/l, reporting antidiabetic medication, or reporting DM diagnosis (with subsequent confirmation by fasting glucose > or = 1.26 g/l or reported antidiabetic medication); all were assessed at semi-annual study visits.

RESULTS

DM developed in 116 HIV-infected and 36 HIV-uninfected women over 6802 person-years. HIV-infected women reporting no recent antiretroviral therapy had a DM incidence rate of 1.53/100 person-years; those reporting HAART containing a protease inhibitor (PI) had a rate of 2.50/100 person-years and those reporting non-PI-containing HAART a rate of 2.89/100 person-years. None of these rates differed from the HIV-uninfected women (1.96/100 person-years) substantially or beyond levels expected by chance. Among HIV-infected women, longer cumulative exposure to nucleoside reverse transcriptase inhibitors (NRTI) was associated with an increased risk of DM incidence compared with no NRTI exposure: relative hazard (RH) 1.81 [95% confidence interval (CI), 0.83-3.93] for > 0 to 3 years exposure and RH 2.64 (95% CI, 1.11-6.32) for > 3 years exposure.

CONCLUSION

Longer cumulative exposure to NRTI was associated with increased DM incidence in HIV-infected women. Regular DM monitoring is advisable because NRTI form the backbone of effective antiretroviral therapy.

Antiretroviral therapies associated with lipoatrophy in HIV-infected women

We previously demonstrated that HIV infection is associated with peripheral and central lipoatrophy in women. We now describe the association of specific antiretroviral drugs (ARV) with body fat changes over a four-year period from 1999 to 2003. 775 HIV-positive and 205 HIV-negative women in the Women's Interagency HIV Study with anthropometric measurements, weight, bioelectric impedance analysis and ARV collected semiannually were included in analysis. Exposure to ARV was defined as report of use for 3 consecutive semiannual study visits. The average 6-month change in weight, percent total body fat, and circumference measurements (i.e., hip, waist, chest, arm, and thigh) was compared between those exposed and those unexposed to the specific ARV for any of the same three consecutive visits. Weight, percent total body fat, and hip, waist, thigh, chest, and arm circumferences decreased in HIV-positive women, but increased in HIV-negative women on average for every six-month interval over the 4-year study period. Among the HIV-positive women, didanosine was the only ARV associated with decreases in circumference measures in the hip (-0.65 cm, 95% confidence interval [CI]: -1.18, -0.12), waist (-0.71 cm, 95% CI: -1.37, -0.04), chest (-0.71 cm, 95% CI: -1.17, -0.26), and arm (-0.23 cm, 95% CI: -0.48, 0.03; p = 0.08). These prospective data suggest that fat loss continues to predominate in HIV-positive women and exposure to didanosine for at least 12 months may further worsen fat loss.

Relation of stavudine discontinuation to anthropometric changes among HIV-infected women

OBJECTIVE

To characterize changes in regional anthropometry associated with stavudine exposure and discontinuation.

DESIGN

Seven hundred thirty-four HIV-infected participants who reported using stavudine (574 of whom later discontinued stavudine) and 698 HIV-uninfected participants from the Women's Interagency HIV Study provided anthropometrics at 8706 semiannual visits between July 1999 and March 2005.

METHODS

Changes in weight, waist, chest, upper arm, hip, and midthigh circumferences were evaluated using linear regression with generalized estimating equations.

RESULTS

HIV-uninfected women demonstrated increases in regional anthropometry at every body site, whereas HIV-infected women demonstrated decreases in weight and circumferences of the waist, chest, hip, and thigh. A smaller annual decrease in hip circumference was seen after discontinuing stavudine for >2.25 years compared with the decrease observed while on stavudine (P = 0.01). Discontinuing stavudine for >2.25 years was associated with smaller (P < 0.05) decreases in hip (-0.06 cm/y) and thigh (-0.005 cm/y) circumference compared with the decreases observed between 1 and 2.25 years (hip: -0.46 cm/y, thigh: -0.24 cm/y) or < or =1 year (hip: -0.64 cm/y, thigh: -0.27 cm/y) after stavudine discontinuation.

CONCLUSIONS

Regardless of continuing or discontinuing stavudine, HIV-infected women demonstrate decreases in weight and body circumference measurements over time. The lower limb seems to be most affected by stavudine exposure, with stabilization observed more than 2 years after discontinuation.

Incidence of lipoatrophy and lipohypertrophy in the women's interagency HIV study

OBJECTIVE

To estimate the incidence of lipoatrophy and lipohypertrophy among HIV-infected and HIV-uninfected women from the Women's Interagency HIV Study.

DESIGN

Eight hundred fifteen women with semiannual data on self-report of bidirectional change in body fat, anthropometric measurements, weight, and bioelectric impedance analysis were included in a 30-month incidence analysis.

METHODS

Lipoatrophy and lipohypertrophy in both peripheral (arms, legs, and buttocks) and central (waist, chest, and upper back) sites were defined by self-report of either a decrease or an increase in a body fat region over the previous 6 months that was confirmed by a corresponding change in anthropometric measurement.

RESULTS

Weight and total body fat increased in HIV-uninfected women but remained stable in HIV-infected women over 30 months. Among HIV-infected women, the incidence of peripheral (relative hazard, 2.1; 95% confidence interval [CI], 1.4-3.3) and central (relative hazard, 1.9; 95% CI, 1.2-2.8) lipoatrophy was about double that among HIV-uninfected women, after adjustment for age and race. The incidence of peripheral lipohypertrophy appeared lower among HIV-infected women than among HIV-uninfected women (relative hazard, 0.8; 95% CI, 0.6-1.1), while the incidence of central lipohypertrophy did not differ by HIV status. Of HIV-infected women with 2 of 4 lipodystrophy outcomes, most (81%) had combined peripheral and central lipoatrophy or combined peripheral and central lipohypertrophy. Only 14% of these women had both peripheral lipoatrophy and central lipohypertrophy.

CONCLUSIONS

These prospective data suggest that lipoatrophy, affecting both peripheral and central sites, predominates in HIV-infected women. The simultaneous occurrence of peripheral lipoatrophy and central lipohypertrophy was uncommon.

Protease inhibitor use and the incidence of diabetes mellitus in a large cohort of HIV-infected women

OBJECTIVE

To assess the association between protease inhibitor (PI) use and the incidence of diabetes mellitus (DM) among participants in the Women's Interagency HIV Study.

DESIGN

Prospective multicenter cohort study. The diagnosis of DM was based on self-report at semiannual interviews conducted from 1994 to 1998.

SETTING

Six inner-city clinical sites in the United States (Brooklyn, NY; Bronx, NY; Washington, DC; Chicago, IL; San Francisco, CA; and Los Angeles, CA).

PARTICIPANTS

A total of 1785 nonpregnant women who had no history of prior DM. The women made up four groups: 1) PI users (n = 609, person-years [PY] at risk = 707); 2) reverse transcriptase inhibitor (RTI)-only users (n = 932, PY = 1486); 3) HIV-infected women reporting no antiretroviral therapy (ART) ever (n = 816, PY = 1480); and 4) HIV-uninfected women (n = 350, PY = 905).

MAIN OUTCOMES

Incidence of DM and median body mass index (BMI) from 1995 to 1998 were compared among the four groups.

RESULTS

Sixty-nine incident cases of DM occurred among 1785 women (1.5 cases per 100 PY; 95% CI: 1.2-1.9). The incidence of DM among PI users was 2.8 cases per 100 PY (2.8%) versus 1.2% among both RTI users and women on no ART (95% CI: 1.6-4.1 [PI]; 0.7-1.8 [RTI and no ART]; P = 0.01 for comparison of the PI group with the RTI group) and 1.4% among HIV-uninfected women (95% CI: 0.7-2.2, P = 0.06 for comparison with PI group). Weight gain was not associated with either PI or RTI use. Multivariate models identified PI use (hazard ratio [HR] = 2.90 [95% CI: 1.50-5.60]; P = 0.002), age (HR = 1.75 per 10 years [95% CI: 1.31-2.34]; P = 0.0002) and BMI as independent risk factors for DM.

CONCLUSIONS

PI use was associated with a threefold increase in the risk of reporting incident DM. Routine screening for diabetes, particularly among older and heavier patients using PI therapy, is advisable.

Tuberculosis in the elderly

As the result of the strengthening of TB-control programs nationwide, a decline in the overall number of reported TB cases in the United States has been observed within the last 10 years. Despite these declines in absolute numbers, the elderly continue to account for a disproportionate share of the cases. The high number of cases diagnosed at autopsy among the elderly suggests that this condition often remains unrecognized, possibly due to the subtle clinical manifestations in this age group. Evidence suggests that, compared with their community-dwelling counterparts, the institutionalized elderly are at a greater risk for re-activation of latent TB and for the acquisition of new TB infection. More studies are needed to make final conclusions. New guidelines for the treatment of LTBI emphasize targeted TST among persons at high risk for development of active TB and no longer use age as an exclusionary condition. All nursing home residents must therefore be regularly screened for LTBI and treated if necessary. Even though elderly persons are at greater risk for hepatic toxicity from TB treatment, the poor outcome of untreated TB in this age group warrants more aggressive treatment of this condition.

Penicillin resistance and other predictors of mortality in pneumococcal bacteremia in a population with high human immunodeficiency virus seroprevalence

Rates of invasive disease caused by penicillin-resistant pneumococci are rising. Previous reports have found no association between resistant pneumococci and increased mortality. To evaluate the impact of penicillin resistance and other variables on mortality, we retrospectively studied all cases of pneumococcal bacteremia identified by our microbiology laboratory from 1 January 1992 through 31 December 1996. There were 462 cases of pneumococcal bacteremia in 432 patients. The mean age was 35 years; 55% of the cases occurred in male patients, 58% were in black patients, and 40% were in Hispanic patients. One-half of the cases occurred in patients with documented human immunodeficiency virus (HIV) infection. Penicillin resistance was first noted in 1994 and increased yearly, accounting for 17% of 1996 isolates. Of all resistant isolates, 65% were resistant to penicillin at a high level. The overall mortality was 17%. On multivariate analysis, high-level penicillin resistance, older age, severe disease, multilobar infiltrates and/or effusion(s) on chest roentgenogram, and Hispanic ethnicity were independent predictors of mortality in pneumococcal bacteremia. In HIV-infected patients, a CD4 cell count below the median just missed statistical significance. This is the first report demonstrating penicillin resistance as an independent predictor of mortality among patients with pneumococcal bacteremia.

Factors influencing time to sputum conversion among patients with smear-positive pulmonary tuberculosis

For hospitalized patients with smear-positive pulmonary or laryngeal tuberculosis, the Centers for Disease Control and Prevention recommends that three consecutive sputum samples be negative for acid-fast bacilli (AFB) before respiratory isolation is discontinued. Limited data are available to predict the length of time to obtain three negative sputum smears and cultures and to determine factors associated with a prolonged interval before sputum smear and culture conversion, especially among patients infected with human immunodeficiency virus (HIV). For 100 consecutive patients with smear-positive pulmonary tuberculosis, the mean and median numbers of days from the initiation of appropriate therapy to the first of three consecutive negative smears were calculated, and associated risk factors were determined. The mean number of days before the first of three consecutive negative sputum smears was 33 days; the median was 23 days. On stepwise multiple regression analysis, cavitary disease, numerous AFB on the initial smear, and no prior history of tuberculosis were the factors independently associated with an increased number of days for both smear and culture conversion. HIV does not prolong the period of infectiousness.