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Severe acute respiratory coronavirus-2 (SARS-CoV-2) is a novel viral pathogen and therefore a challenge to accurately diagnose infection. Asymptomatic cases are common and so it is difficult to accurately identify infected cases to support surveillance and case detection. Diagnostic test developers are working to meet the global demand for accurate and rapid diagnostic tests to support disease management. However, the focus of many of these has been on molecular diagnostic tests, and more recently serologic tests, for use in primarily high-income countries. Low- and middle-income countries typically have very limited access to molecular diagnostic testing due to fewer resources. Serologic testing is an inappropriate surrogate as the early stages of infection are not detected and misdiagnosis will promote continued transmission. Detection of infection via direct antigen testing may allow for earlier diagnosis provided such a method is sensitive. Leading SARS-CoV-2 biomarkers include spike protein, nucleocapsid protein, envelope protein, and membrane protein. This research focuses on antibodies to SARS-CoV-2 spike protein due to the number of monoclonal antibodies that have been developed for therapeutic research but also have potential diagnostic value. In this study, we assessed the performance of antibodies to the spike glycoprotein, acquired from both commercial and private groups in multiplexed liquid immunoassays, with concurrent testing via a half-strip lateral flow assays (LFA) to indicate antibodies with potential in LFA development. These processes allow for the selection of pairs of high-affinity antispike antibodies that are suitable for liquid immunoassays and LFA, some of which with sensitivity into the low picogram range with the liquid immunoassay formats with no cross-reactivity to other coronavirus S antigens. Discrepancies in optimal ranking were observed with the top pairs used in the liquid and LFA formats. These findings can support the development of SARS-CoV-2 LFAs and diagnostic tools.

This study examined the efficacy of the OncoE6™ Cervical Test, careHPV™ and visual inspection with acetic acid (VIA) in identifying women at risk for cervical cancer and their capability to detect incident cervical precancer and cancer at 1-year follow-up. In a population of 7,543 women living in rural China, women provided a self-collected and two clinician-collected specimens and underwent VIA. All screen positive women for any of the tests, a ∼ 10% random sample of test-negative women that underwent colposcopy at baseline, and an additional ∼ 10% random sample of test-negative women who did not undergo colposcopy at baseline (n = 3,290) were recruited. 2,904 women were rescreened 1 year later using the same tests, colposcopic referral criteria, and procedures. Sensitivities of baseline tests to detect 1-year cumulative cervical intraepithelial neoplasia Grade 3 or cancer (CIN3+) were 96.5% and 81.6% for careHPV™ on clinician-collected and self-collected specimens, respectively, and 54.4% for OncoE6™ test. The OncoE6™ test was very specific (99.1%) and had the greatest positive predictive value (PPV; 47.7%) for CIN3+. Baseline and 1-year follow-up cervical specimens testing HPV DNA positive was sensitive (88.0%) but poorly predictive (5.5-6.0%) of incident CIN2+, whereas testing repeat HPV16, 18 and 45 E6 positive identified only 24.0% of incident CIN2+ but had a predictive value of 33.3%. This study highlights the different utility of HPV DNA and E6 tests, the former as a screening and the latter as a diagnostic test, for detection of cervical precancer and cancer.

Objective To examine the influence of human papillomavirus (HPV) genotypes on the sensitivity of visual inspection with acetic acid (VIA) for screening, and colposcopy for diagnosis of cervical intraepithelial neoplasia grade 2 (CIN2) or more severe (CIN2+). Materials and methods Women aged 25 to 65 years from China (n = 7,541) were screened with 6 tests (careHPV and Hybrid Capture 2 on self- and clinician-collected specimens; HPV-16, HPV-18, HPV-45 E6 detection; and VIA). Biopsies from women with a diagnosis of CIN2+ underwent testing for 25 HPV genotypes using SPF10/LiPA. Human papillomavirus genotyping results were classified according to broad categories of cancer risk. Results Among the 143 women with a diagnosis of CIN2+, the percentage who were HPV16 positive increased with increasing severity of diagnosis: 33.3% for CIN2 (n = 39), 69.1% for CIN3 (n = 94), and 90% for cancer (n = 10). There was a higher percentage of HPV-16 in women with abnormal colposcopic impression (p = .007) and positive VIA (p = .02) than normal colposcopy and negative VIA, respectively. Colposcopy and VIA were more sensitive to detect CIN2+ among HPV-16- and/or HPV-18-positive women than HPV-16-/HPV-18-negative women (67.4% vs 43.1%, p = .008, for colposcopy; and 53.3% vs 37.3%, p = .08, for VIA). Conclusions Human papillomavirus type 16 is related to more clear visual acetowhite changes in the epithelium. Therefore, we should expect a reduction of the performance of VIA for cervical cancer screening to identify women with CIN2+, and reduction of the performance of colposcopy to diagnose CIN2+, in vaccinated populations.

Background The uptake of HIV testing has increased in sub-Saharan Africa over the past three decades. However, the proportion of people aware of their HIV status remains lower than required to change the pandemic. HIV self-testing (HIVST) may meet this gap. Assessment of readiness for and the acceptability of HIVST by lay users in South Africa is limited. This paper presents results from a formative study designed to assess the perceived usability and acceptability of HIVST among lay users using several self-test prototypes. Fifty lay users were purposively selected from rural and peri-urban KwaZulu-Natal, South Africa. Acceptability of HIVST was assessed using a simple post-test quantitative assessment tool addressing confidence, ease-of-use, intended future use and willingness to pay. In-depth qualitative interviews explored what participants felt about the HIVST and why, their willingness to recommend and how much they would pay for a test. Results The key finding is that there is high acceptability regardless of self-test prototype. Acceptability is framed by two domains: usability and perceived need. Perceived usability was explored through perceived ease of use, which, regardless of actual correct usage, was reported by many of the respondents. Acceptability is influenced by perceived need, expressed by many who felt that the need for the self-test to protect privacy and autonomy. Ease of access and widespread availability of the test, not at a significant cost, were also important factors. Many participants would recommend self-test use to others and also indicated that they would choose to conduct the test again if it was free while some also indicated being willing to buy a test. Conclusions The positive response and readiness amongst lay users for an HIVST in this context prototype suggests that there would be a ready and willing market for HIVST. For scalability and sustainability usability, including access and availability that are here independent indications of acceptability, should be considered. So too should the desire for future use, as an additional factor pointing to acceptability. The results show high acceptability in all of these areas domains and a general interest in HIVST amongst lay users in a community in KwaZulu-Natal.

careHPV is a new, lower-cost DNA test for human papillomavirus (HPV). There are limited analytic comparisons of careHPV against a referent HPV DNA test like Hybrid Capture 2 (HC2).To assess the test agreement between careHPV and HC2 on self- and clinician-collected specimens.In a population of 7541 women living in rural China, women provided a self-collected (sc) and two clinician-collected (cc) specimens and underwent visual inspection after acetic acid (VIA). The sc specimen and one cc specimen were tested by careHPV and HC2; a random subset of specimens was tested for HPV genotypes.The percent positive on cc specimens and sc specimens was 14.69% and 14.97% for careHPV, respectively, and 15.05% and 18.53% for HC2, respectively; HC2 testing of sc specimens was more likely to test positive than other combinations of tests and specimens (p0.0001 for all comparisons). The agreement between different tests on the same specimens (kappa=0.787 and 0.691 for cc and sc specimens, respectively) was better than the same test on different specimens (kappa=0.653 and 0.649 for HC2 and careHPV, respectively). Disagreement between the same test on different specimens increased with increasing participant age (ptrend=0.0001 for HC2 and 0.002 for careHPV). HC2-positive/careHPV-negative specimens were more likely to test positive for non-carcinogenic HPV genotype than test HPV negative whereas the converse was true for HC2-negative/careHPV-positive specimens.The agreement for HPV DNA detection between careHPV and HC2 was good to very good.

HIV self-testing (HIVST) is increasingly being sought and offered globally, yet there is limited information about the test features that will be required for an HIV self-test to be easy to use, acceptable to users, and feasible for manufacturers to produce. We conducted formative usability research with participants who were naive to HIVST using five prototypes in Kenya, Malawi, and South Africa. The tests selected ranged from early-stage prototypes to commercially ready products and had a diverse set of features. A total of 150 lay users were video-recorded conducting unsupervised self-testing and interviewed to understand their opinions of the test. Participants did not receive a test result, but interpreted standardized result panels. This study demonstrated that users will refer to the instructions included with the test, but these can be confusing or difficult to follow. Errors were common, with less than 25 % of participants conducting all steps correctly and 47.3 % of participants performing multiple errors, particularly in sample collection and transfer. Participants also had difficulty interpreting results. To overcome these issues, the ideal HIV self-test requires pictorial instructions that are easy to understand, simple sample collection with integrated test components, fewer steps, and results that are easy to interpret.

careHPV, a lower-cost DNA test for human papillomavirus (HPV), is being considered for cervical cancer screening in low- and middle-income countries. However, not a single large-scaled study exists to investigate the optimal positive cutoff point of careHPV test. We pooled data for 9,785 women participating in two individual studies conducted from 2007 to 2011 in rural China. Woman underwent multiple screening tests, including careHPV on clinician-collected specimens (careHPV-C) and self-collected specimens (careHPV-S), and Hybrid Capture 2 on clinician-collected specimens (HC2-C) as a reference standard. The primary endpoint was cervical intraepithelial neoplasia grade 3 or more severe (CIN3+) ( n = 127), and secondary endpoint was CIN2+ ( n = 213). The area under the curves (AUCs) for HC2-C and careHPV-C were similar (0.954 versus 0.948, P = 0.166), and better than careHPV-S (0.878; P < 0.001 versus both). The optimal positive cutoff points for HC2-C, careHPV-C, and careHPV-S were 1.40, 1.74, and 0.85, respectively. At the same cutoff point, careHPV-C was not significantly less sensitive and more specific for CIN3+ than HC2-C, and careHPV-S was significantly less sensitive for CIN3+ than careHPV-C and HC2-C. Raising the cutoff point of careHPV-C from 1.0 to 2.0 could result in nonsignificantly lower sensitivity but significantly higher specificity. Similar results were observed using CIN2+ endpoint. careHPV using either clinician- or self-collected specimens performed well in detecting cervical precancer and cancer. We found that the optimal cutoff points of careHPV were 2.0 on clinician-collected specimens and 1.0 on self-collected specimens.

Objective To examine the determinants of a positive visual inspection after acetic acid (VIA), including the relationship of testing positive for high-risk human papillomavirus (HR-HPV), which is the necessary cause of cervical cancer. Design A prospective cohort study. Setting Three clinical sites in rural China. Population A total of 7541 women aged 25–65 years. Methods All women underwent VIA, DNA testing, by two DNA tests performed on both clinician- and self-collected specimens, and HPV E6 oncoprotein testing. Those positive by any test underwent colposcopy and four-quadrant biopsy evaluation. A random sample of women with negative screening results also underwent colposcopy and, if colposcopic abnormalities were observed, four-quadrant biopsy evaluation was performed. Women diagnosed with cervical intraepithelial neoplasia grade 2 (CIN2), or more severe grades (CIN2 + ), underwent treatment. Main outcome measure Testing positive for VIA. Results Overall, 7.6% (95% confidence interval, 95% CI, 7.0–8.2%) had a positive VIA. Women who tested positive for HPV were more likely to have a positive VIA than women who tested negative for HPV (15.0%, 95% CI 12.9–17.2% versus 6.3%, 95% CI 5.7–6.9%; P

New, lower-cost tests that target high-risk human papillomavirus (HR-HPV) have been developed for cervical cancer screening in lower-resource settings but large, population-based screening studies are lacking. Women ages 25 to 65 years and living in rural China (n = 7,543) self-collected a cervicovaginal specimen, had 2 cervical specimens collected by a clinician, and underwent visual inspection after acetic acid (VIA). The self- and one clinician-collected specimens underwent HR-HPV DNA testing by careHPV (QIAGEN) and Hybrid Capture 2 (HC2; QIAGEN) and the other clinician-collected specimen was tested for HPV16, 18, and 45 E6 using OncoE6 (Arbor Vita Corporation). Women who screened positive for any test and a random sample of those negative on all tests underwent colposcopic evaluation. The percent test positive was 1.8% for HPV E6 oncoprotein, between 14% and 18% for HR-HPV DNA testing, and 7.3% for VIA. The sensitivity for cervical intraepithelial neoplasia grade 3 or more severe (CIN3+; n = 99) was 53.5% for OncoE6, 97.0% for both careHPV and HC2 testing of the clinician-collected specimen, 83.8% for careHPV testing and 90.9% for HC2 testing of the self-collected specimen, and 50.5% for VIA. OncoE6 had the greatest positive predictive value (PPV), at 40.8% for CIN3+, compared with the other tests, which had a PPV of less than 10%. OncoE6 tested 70.3% positive for HPV16, 18, or 45-positive CIN3+ and tested negative for all HPV16-, 18-, or 45-negative CIN3+ (P < 0.0001). HPV E6 oncoprotein detection is useful for identifying women who have cervical precancer and cancer. Cancer Prev Res; 6(9); 938–48. ©2013 AACR.

Summary Background A new test ( care HPV; QIAGEN, Gaithersburg, MD, USA) has been developed to detect 14 high-risk types of carcinogenic human papillomavirus (HPV) in about 2·5 h, to screen women in developing regions for cervical intraepithelial neoplasia (CIN). We did a cross-sectional study to assess the clinical accuracy of care HPV as a rapid screening test in two county hospitals in rural China. Methods From May 10 to June 15, 2007, the care HPV test was done locally by use of self-obtained vaginal and provider-obtained cervical specimens from a screening population-based set of 2530 women aged 30 to 54 years in Shanxi province, China. All women were assessed by visual inspection with acetic acid (VIA), Digene High-Risk HPV HC2 DNA Test (HC2), liquid-based cytology, and colposcopy with directed biopsy and endocervical curettage as necessary. In 2388 women with complete data, 441 women with negative colposcopy, but unsatisfactory or abnormal cytology or who were positive on HC2 or the new care HPV test, were recalled for a second colposcopy, four-quadrant cervical biopsies, and endocervical curettage. An absence of independence between the tests was not adjusted for and the Bonferroni correction was used for multiple comparisons. Findings Complete data were available for 2388 (94·4%) women. 70 women had CIN2+ (moderate or severe CIN or cancer), of whom 23 had CIN3+. By use of CIN2+ as the reference standard and area-under-the-curve analysis with a two-sided alpha error level of 0·0083, the sensitivities and specificities of the care HPV test for a cut-off ratio cut-point of 0·5 relative light units, were 90·0% (95% CI 83·0–97·0) and 84·2% (82·7–85·7), respectively, on cervical specimens, and 81·4% (72·3–90·5) and 82·4% (80·8–83·9), respectively, on vaginal specimens (areas under the curve not significantly different, p=0·0596), compared with 41·4% (29·9–53·0) and 94·5% (93·6–95·4) for VIA (areas under the curve significantly different, p=0·0001 and p=0·0031, for cervical and vaginal-specimen comparisons for the care HPV test, respectively). The sensitivity and specificity of HC2 for cervical specimens were 97·1% (93·2–100) and 85·6% (84·2–87·1), respectively (areas under the curve not significantly different from the care HPV test on cervical specimens, p=0·0163). Interpretation The care HPV test is promising as a primary screening method for cervical-cancer prevention in low-resource regions. Funding Bill & Melinda Gates Foundation.

Background Serological assays for human IgG4 to the Onchocerca volvulus antigen Ov16 have been used to confirm elimination of onchocerciasis in much of the Americas and parts of Africa. A standardized source of positive control antibody (human anti-Ov16 IgG4) will ensure the quality of surveillance data using these tests. Methodology/Principal Findings A recombinant human IgG4 antibody to Ov16 was identified by screening against a synthetic human Fab phage display library and converted into human IgG4. This antibody was developed into different positive control formulations for enzyme-linked immunosorbent assay (ELISA) and rapid diagnostic test (RDT) platforms. Variation in ELISA results and utility as a positive control of the antibody were assessed from multiple laboratories. Temperature and humidity conditions were collected across seven surveillance activities from 2011–2014 to inform stability requirements for RDTs and positive controls. The feasibility of the dried positive control for RDT was evaluated during onchocerciasis surveillance activity in Togo, in 2014. When the anti-Ov16 IgG4 antibody was used as a standard dilution in horseradish peroxidase (HRP) and alkaline phosphatase (AP) ELISAs, the detection limits were approximately 1ng/mL by HRP ELISA and 10ng/mL by AP ELISA. Positive control dilutions and spiked dried blood spots (DBS) produced similar ELISA results. Used as a simple plate normalization control, the positive control antibody may improve ELISA data comparison in the context of inter-laboratory variation. The aggregate temperature and humidity monitor data informed temperature parameters under which the dried positive control was tested and are applicable inputs for testing of diagnostics tools intended for sub-Saharan Africa. As a packaged positive control for Ov16 RDTs, stability of the antibody was demonstrated for over six months at relevant temperatures in the laboratory and for over 15 weeks under field conditions. Conclusions The recombinant human anti-Ov16 IgG4 antibody-based positive control will benefit inter-laboratory validation of ELISA assays and serve as quality control (QC) reagents for Ov16 RDTs at different points of the supply chain from manufacturer to field use., Author Summary Serological markers such as antibody responses to pathogen-specific antigens are used to inform disease epidemiology in many elimination programs. A major challenge with program-scale serological testing, and with any diagnostic test validation, is access to consistent and unlimited control reagents with which to provide assay QC and facilitate data consolidation. In the context of disease elimination, clinical positive sera will be particularly difficult to source and use as routine, inter-laboratory reagents. This study reports on a recombinant antibody specific against a key serological marker for onchocerciasis: its selection, testing, and incorporation into protocols across relevant immunoassay platforms. We have demonstrated it is a viable reagent for integration into QC and QA protocols to support long-term serological testing for onchocerciasis to support disease elimination efforts. This approach should be generalizable to other diagnostic tools supporting programs to achieve the 2020 goals of the London Declaration on Neglected Tropical Diseases.

In a feasibility study using a prototype, lateral-flow test for human papillomavirus type 16, 18, and/or 45 (HPV16/18/45) E6 oncoproteins, 51 of 75 (68%; 95% confidence interval [95% CI] of 56 to 78%) of HPV16/18/45 DNA-positive specimens from women with a diagnosis of CIN3+ (cervical intraepithelial neoplasia grade 3+ or cervical cancer) tested positive for HPV16/18/45 E6 oncoprotein. None of 16 (95% CI of 0 to 37%) HPV16/18/45 DNA-positive cervical specimens from women with a negative or CIN1 diagnosis tested positive for HPV16/18/45 E6 oncoprotein.

Cervical cancer kills 230 000 women annually. Low-resource regions of the world are disproportionately burdened with 80% of the cases. Efficient screening methods are the key to decreasing the death toll from this disease. High-risk human papillomavirus (HPV) types have been identified as the etiological agent for >99% of cervical cancers. Infection with HPV is ubiquitous and is often resolved by the host. High-risk HPV infections leading to cervical cancer require the production of both HPV E6 and E7 oncoproteins (1)(2)(3)(4)(5). Thus, an assay capable of detecting high-risk HPV E6 from cervical swab samples may have a high positive predictive value and may help to accurately identify women at increased risk of progression to cancer. Internal studies have shown that cervical cancer cell lines produce ∼1 ng of E6 per 1 000 000 cells (data not shown). Work is continuing to quantify E6 amounts in cervical cell samples from clients with cancer, high-grade lesions (cervical intraepithelial neoplasia 2/3), and low-grade lesions (cervical intraepithelial neoplasia 1). Protein determinations performed on provider-collected cervical swabs indicate that the swabs collect 500 000 …

Using human papillomavirus (HPV) testing for cervical cancer screening in lower-resource settings (LRS) will result in a significant number of screen-positive women. This analysis compares different triage strategies for detecting cervical precancer and cancer among HPV-positive women in LRS. This was a population-based study of women aged 25–65 years living in China (n = 7,541). Each woman provided a self-collected and two clinician-collected specimens. The self-collected and one clinician-collected specimen were tested by two HPV DNA tests—careHPV™ and Hybrid Capture 2; the other clinician-collected specimen was tested for HPV16/18/45 E6 protein. CareHPV™-positive specimens were tested for HPV16/18/45 DNA. HPV DNA-positive women underwent visual inspection with acetic acid (VIA) and then colposcopic evaluation with biopsies. The performance for detection of cervical intraepithelial neoplasia grade 3 or cancer (CIN3+) among HPV DNA-positive women was assessed for different triage strategies: HPV16/18/45 E6 or DNA detection, VIA, colposcopic impression, or higher signal strength (≥10 relative light units/positive control [rlu/pc]). The percent triage positive ranges were 14.8–17.4% for VIA, 17.8–20.9% for an abnormal colposcopic impression; 7.9–10.5% for HPV16/18/45 E6; 23.4–28.4% for HPV16/18/45 DNA; and 48.0–62.6% for higher signal strength (≥10 rlu/pc), depending on the HPV test/specimen combination. The positivity for all triage tests increased with severity of diagnosis. HPV16/18/45 DNA detection was approximately 70% sensitive and had positive predictive values (PPV) of approximately 25% for CIN3+. HPV16/18/45 E6 detection was approximately 50% sensitive with a PPV of nearly 50% for CIN3+. Different triage strategies for HPV DNA-positive women provide important tradeoffs in colposcopy or treatment referral percentages and sensitivity for prevalent CIN3+. What's new? The careHPV™ test is a novel technology for primary cervical cancer screening of women from lower-resource settings. However, triage strategies are needed to identify which HPV-positive women are at highest risk of cervical precancer and cancer. Here, multiple viable and affordable strategies to manage HPV-positive women depending on local requirements and resources are identified, based on evaluation of the performance of different triage strategies for developing countries. The different strategies for women who test positive for HPV DNA provide important tradeoffs in colposcopy or treatment referral percentages and sensitivity for cervical intraepithelial neoplasia grade 3 or cancer (CIN3+).

Gestational diabetes is a global epidemic where many urban areas in Southeast Asia have found prevalence rates as high as 20%, exceeding the highest prevalence rates in the developed world. It can have serious and life-threatening consequences for mothers and babies. We are developing two variants of a new, simple, low-cost rapid test for screening for gestational diabetes mellitus for use primarily in low-resource settings. The pair of assays, both semiquantitative rapid diagnostic strip tests for glycated albumin, require neither fasting nor an oral glucose challenge test. One variant is an extremely simple strip test to estimate the level of total glycated albumin in blood. The other, which is slightly more complex and expensive, is a test that determines the ratio of glycated albumin to total albumin. The screening results can be used to refer women to receive additional care during delivery to avoid birth complications as well as counseling on diet and exercise during and after pregnancy. Results with the latter test may also be used to start treatment with glucose-lowering drugs. Both assays will be read visually. We present initial results of a preliminary cost-performance comparison model evaluating the proposed test versus existing alternatives. We also evaluated user needs and schematic paper microfluidics-based designs aimed at overcoming the challenge of visualizing relatively narrow differences between normal and elevated levels of glycated albumin in blood.

BACKGROUND: Liquid-based cytology (LBC) has been compared with conventional cytology in numerous studies. In the current study of 2 LBC systems, the accuracy, rates of unsatisfactory cytology, and sufficiency of residual LBC specimens for Hybrid Capture 2 (HC2) HPV DNA testing were compared. METHODS: Eligible women ages 30 to 49 years were recruited for this cross-sectional population-based study in rural China. Women were assessed by visual inspection with acetic acid (VIA), LBC, and high-risk HPV HC2 DNA assay. Cervical specimens were preserved according to SurePath or ThinPrep protocols. LBC results were manually read. HC2 testing was performed on specimens with sufficient residual volume. Colposcopies and biopsies were performed on women who were VIA positive at the time of initial screening. Women with abnormal LBC or HC2 test results were called back for colposcopies and 4-quadrant cervical biopsies. RESULTS: Of 2005 eligible women, 972 were tested by SurePath and 1033 by ThinPrep. Compared with SurePath samples, ThinPrep samples had higher rates of unsatisfactory cytology (0.2% for SurePath and 1.5% for ThinPrep) and insufficient residual volume for HC2 (0.0% for SurePath and 18.2% for ThinPrep). SurePath samples yielded higher sensitivities and similar specificities for LBC and HC2 testing of residual specimens, but these differences were not determined to be significant by area-under-the-curve analysis (LBC performance: 0.89 for SurePath and 0.85 for ThinPrep; HC2 performance: 0.91 for SurePath and 0.89 for ThinPrep). CONCLUSIONS: Both methods yielded similar validity in detecting significant cervical lesions. However, SurePath samples yielded higher rates of satisfactory LBC slides and sufficient residual volume for HC2. Cancer (Cancer Cytopathol) 2011;000:000–000. V C 2011 American Cancer Society.

South Africa bears the world's largest burden of HIV with over 6.4 million people living with the virus. The South African government's response to HIV has yielded remarkable results in recent years; over 13 million South Africans tested in a 2012 campaign and over 2 million people are on antiretroviral treatment. However, with an HIV & AIDS and STI National Strategic Plan aiming to get 80 percent of the population to know their HIV status by 2016, activists and public health policy makers argue that non-invasive HIV self-testing should be incorporated into the country HIV Counseling and Testing [HCT] portfolios. In-depth qualitative interviews (N = 12) with key stakeholders were conducted from June to July 2013 in South Africa. These included two government officials, four non-governmental stakeholders, two donors, three academic researchers, and one international stakeholder. All stakeholders were involved in HIV prevention and treatment and influenced HCT policy and research in South Africa and beyond. The interviews explored: interest in HIV self-testing; potential distribution channels for HIV self-tests to target groups; perception of requirements for diagnostic technologies that would be most amenable to HIV self-testing and opinions on barriers and opportunities for HIV-linkage to care after receiving positive test results. While there is currently no HIV self-testing policy in South Africa, and several barriers exist, participants in the study expressed enthusiasm and willingness for scale-up and urgent need for further research, planning, establishment of HIV Self-testing policy and programming to complement existing facility-based and community-based HIV testing systems. Introduction of HIV self-testing could have far-reaching positive effects on holistic HIV testing uptake, giving people autonomy to decide which approach they want to use for HIV testing, early diagnosis, treatment and care for HIV particularly among hard-to reach groups, including men.

Introduction : HIV self-testing (HIVST) has the potential to increase uptake of HIV testing among untested populations in sub-Saharan Africa and is on the brink of scale-up. However, it is unclear to what extent HIVST would be supported by stakeholders, what policy frameworks are in place and how variations between contexts might influence country-preparedness for scale-up. This qualitative study assessed the perceptions of HIVST among stakeholders in three sub-Saharan countries. Methods : Fifty-four key informant interviews were conducted in Kenya ( n =16), Malawi ( n =26) and South Africa ( n =12) with government policy makers, academics, activists, donors, procurement specialists, laboratory practitioners and health providers. A thematic analysis was conducted in each country and a common coding framework allowed for inter-country analysis to identify common and divergent themes across contexts. Results : Respondents welcomed the idea of an accurate, easy-to-use, rapid HIV self-test which could increase testing across all populations. High-risk groups, such as men, Men who have sex with men (MSM), couples and young people in particular, could be targeted through a range of health facility and community-based distribution points. HIVST is already endorsed in Kenya, and political support for scale-up exists in South Africa and Malawi. However, several caveats remain. Further research, policy and ensuing guidelines should consider how to regulate, market and distribute HIVST, ensure quality assurance of tests and human rights, and critically, link testing to appropriate support and treatment services. Low literacy levels in some target groups would also need context-specific consideration before scale up. World Health Organization (WHO) policy and regulatory frameworks are needed to guide the process in those areas which are new or specific to self-testing. Conclusions : Stakeholders in three HIV endemic sub-Saharan countries felt that HIVST will be an important complement to existing community and facility-based testing approaches if accompanied by the same essential components of any HIV testing service, including access to accurate information and linkages to care. While there is an increasingly positive global policy environment regarding HIVST, several implementation and social challenges limit scale-up. There is a need for further research to provide contextual and operational evidence that addresses concerns and contributes to normative WHO guidance. Keywords: HIVST; country readiness; policy and political support for self-testing; HIV testing; opportunities and limitations of self-tests. To access the supplementary material to this article please see Supplementary Files in the column to the right (under Article Tools). (Published: 20 March 2015) Citation: van Rooyen H et al. Journal of the International AIDS Society 2015, 18 :19445 http://www.jiasociety.org/index.php/jias/article/view/19445 | http://dx.doi.org/10.7448/IAS.18.1.19445

Probably the most common single discriminant algorithm in use today is the linear algorithm. Unfortunately, this algorithm has been shown to frequently behave poorly in high dimensions relative to other algorithms, even on suitable Gaussian data. This is because the algorithm uses sample estimates of the means and covariance matrix which are of poor quality in high dimensions. It seems reasonable that if these unbiased estimates were replaced by estimates which are more stable in high dimensions, then the resultant modified linear algorithm should be an improvement. This paper studies using a shrinkage estimate for the covariance matrix in the linear algorithm. We chose the linear algorithm, not because we particularly advocate its use, but because its simple structure allows one to more easily ascertain the effects of the use of shrinkage estimates. A simulation study assuming two underlying Gaussian populations with common covariance matrix found the shrinkage algorithm to significantly outperform the standard linear algorithm in most cases. Several different means, covariance matrices, and shrinkage rules were studied. A nonparametric algorithm, which previously had been shown to usually outperform the linear algorithm in high dimensions, was included in the simulation study for comparison.

Background Diagnostics provide a means to measure progress toward disease elimination. Many countries in Africa are approaching elimination of onchocerciasis after successful implementation of mass drug administration programs as well as vector control. An understanding of how markers for infection such as skin snip microfilaria and Onchocerca volvulus-specific seroconversion perform in near-elimination settings informs how to best use these markers. Methods All-age participants from 35 villages in Togo were surveyed in 2013 and 2014 for skin snip Onchocerca volvulus microfilaria and IgG4 antibody response by enzyme-linked immunosorbent assay (ELISA) to the Onchocerca volvulus-specific antigen Ov16. A Gaussian mixture model applying the expectation-maximization (EM) algorithm was used to determine seropositivity from Ov16 ELISA data. For a subset of participants (n = 434), polymerase chain reaction (PCR) was performed on the skin snips taken during surveillance. Results Within the 2,005 participants for which there was Ov16 ELISA data, O. volvulus microfilaremia prevalence and Ov16 seroprevalence were, 2.5 and 19.7 %, respectively, in the total population, and 1.6 and 3.6 % in children under 11. In the subset of 434 specimens for which ELISA, PCR, and microscopy data were generated, it was found that in children under 11 years of age, the anti-Ov16 IgG4 antibody response demonstrate a sensitivity and specificity of 80 and 97 %, respectively, against active infections as determined by combined PCR and microscopy on skin snips. Further analysis was performed in 34 of the 35 villages surveyed. These villages were stratified by all-age seroprevalence into three clusters: < 15 %; 15–20 %; and > 20 %. Age-dependence of seroprevalence for each cluster was best reflected by a two-phase force-of-infection (FOI) catalytic model. In all clusters, the lower of the two phases of FOI was associated with a younger age group, as reflected by the seroconversion rates for each phase. The age at which transition from lower to higher seroconversion, between the two phases of FOI, was found to be highest (older) for the cluster of villages with