Enteric Diseases

ABSTRACT
HIV-1 infection continues to be a global health challenge and a vaccine is urgently needed. Broadly neutralizing antibodies (bNAbs) are considered essential as they inhibit multiple HIV-1 strains, but they are difficult to elicit by conventional immunization. In contrast, non-neutralizing antibodies that correlated with reduced risk of infection in the RV144 HIV vaccine trial are relatively easy to induce, but responses are not durable. To overcome these obstacles, adeno-associated virus (AAV) vectors were used to provide long-term expression of antibodies targeting the V2 region of the HIV-1 envelope protein, including the potent CAP256-VRC26.25 bNAb, as well as non-neutralizing CAP228 antibodies that resemble those elicited by vaccination.

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ABSTRACT
The substitution of moxifloxacin for ethambutol produced promising results for improved tuberculosis (TB) treatment outcomes.

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ABSTRACT
The aims of this study were to determine the prevalence of risk factors associated with hepatocellular carcinoma (HCC) in black adult South Africans and to estimate the size of the associated risks

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ABSTRACT
The genital tract of African women has been shown to differ from what is currently accepted as ‘normal’, defined by a pH≤4.5 and lactobacilli-dominated microbiota. Adolescent girls and young women (AGYW) from sub-Saharan Africa are at high risk for HIV, and we hypothesized that specific biological factors are likely to be influential. This study aimed to compare characteristics of vaginal health in HIV-negative AGYW (16-22-years-old), from two South African communities, to international norms. We measured plasma hormones, vaginal pH, presence of BV (Nugent scoring), sexually transmitted infections (multiplex PCR for Chlamydia trachomatisNeisseria gonorrhoeaTrichomonas vaginalisMycoplasma genitalium) and candidiasis (Gram stain) in AGYW (n = 298) from Cape Town and Soweto. 

ABSTRACT
The VH1-2 restricted VRC01-class of antibodies targeting the HIV envelope CD4 binding site are a major focus of HIV vaccine strategies. However, a detailed analysis of VRC01-class antibody development has been limited by the rare nature of these responses during natural infection and the lack of longitudinal sampling of such responses. To inform vaccine strategies, we mapped the development of a VRC01-class antibody lineage (PCIN63) in the subtype C infected IAVI Protocol C neutralizer PC063.

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We describe the extent of and variables associated with irreproducible HIV-1 PCR positive results within South Africa’s Early Infant Diagnosis (EID) program from 2010 to 2015 and propose criteria for differentiating indeterminate from clearly positive results using the COBAS® AmpliPrep/COBAS® TaqMan HIV-1 Qualitative Test version 2.0 (CAP/CTM Qual v2.0). Fourteen percent of specimens with an instrument-positive result that were repeat-tested yielded a negative result for which cycle threshold (Ct) proved to be the only predictive variable. A Ct <33.0 was found to be the most accurate threshold value for differentiating clearly positive from irreproducible cases, correctly predicting 96.8% of results. Among 70 patients with an irreproducible positive result linked to a follow up HIV-1 PCR test, 67 (95.7%) were negative and 3 (4.3%) were instrument-positive. Criteria differentiating clearly positive from indeterminate results need to be retained within EID services and infants with indeterminate results closely monitored and final HIV status determined.

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Ninety percent of the world’s HIV-positive pregnant women live in 22 countries. These 22 countries, including South Africa (SA) have prioritised the elimination of mother-to-child transmission of HIV (EMTCT). Since 2016 all 22 countries recommend lifelong antiretroviral treatment for all HIV-positive pregnant and lactating women. To measure South African national, provincial and district-level progress towards attaining EMTCT, we analysed the number of in utero (IU) paedatric HIV infections per 100 000 live births (IU case rate), and synthesised factors hindering the monitoring of EMTCT progress and attainment from the viewpoint of provincial and district-level healthcare managers and implementers. We highlight potential innovations to strengthen health systems and improve EMTCT programme delivery.

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Identifying and addressing gaps in the prevention of mother-to-child transmission of HIV (PMTCT) is required if South Africa (SA) is to achieve targets for eliminating MTCT (eMTCT). Potential PMTCT gaps that increase MTCT risk include late maternal HIV diagnosis, lack of or delayed antiretroviral therapy (ART) during pregnancy and breastfeeding, and lack of effective prophylaxis for HIV-exposed infants.

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Differentiating clearly positive from indeterminate results: A review of irreproducible HIV-1 PCR positive samples from South Africa's Early Infant Diagnosis Program

We describe the extent of and variables associated with irreproducible HIV-1 PCR positive results within South Africa’s Early Infant Diagnosis (EID) program from 2010 to 2015 and propose criteria for differentiating indeterminate from clearly positive results using the COBAS® AmpliPrep/COBAS® TaqMan HIV-1 Qualitative Test version 2.0 (CAP/CTM Qual v2.0). Fourteen percent of specimens with an instrument-positive result that were repeat-tested yielded a negative result for which cycle threshold (Ct) proved to be the only predictive variable. A Ct <33.0 was found to be the most accurate threshold value for differentiating clearly positive from irreproducible cases, correctly predicting 96.8% of results. Among 70 patients with an irreproducible positive result linked to a follow up HIV-1 PCR test, 67 (95.7%) were negative and 3 (4.3%) were instrument-positive. Criteria differentiating clearly positive from indeterminate results need to be retained within EID services and infants with indeterminate results closely monitored and final HIV status determined.

Closing the gaps to eliminate mother-to-child transmission of HIV (MTCT) in South Africa: Understanding MTCT case rates, factors that hinder the monitoring and attainment of targets, and potential game changers.

Ninety percent of the world’s HIV-positive pregnant women live in 22 countries. These 22 countries, including South Africa (SA) have prioritised the elimination of mother-to-child transmission of HIV (EMTCT). Since 2016 all 22 countries recommend lifelong antiretroviral treatment for all HIV-positive pregnant and lactating women. To measure South African national, provincial and district-level progress towards attaining EMTCT, we analysed the number of in utero (IU) paedatric HIV infections per 100 000 live births (IU case rate), and synthesised factors hindering the monitoring of EMTCT progress and attainment from the viewpoint of provincial and district-level healthcare managers and implementers. We highlight potential innovations to strengthen health systems and improve EMTCT programme delivery.

Near-real-time tracking of gaps in prevention of mother-to-child transmission of HIV in three districts of KwaZulu-Natal Province, South Africa.

Identifying and addressing gaps in the prevention of mother-to-child transmission of HIV (PMTCT) is required if South Africa (SA) is to achieve targets for eliminating MTCT (eMTCT). Potential PMTCT gaps that increase MTCT risk include late maternal HIV diagnosis, lack of or delayed antiretroviral therapy (ART) during pregnancy and breastfeeding, and lack of effective prophylaxis for HIV-exposed infants.