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Item T‑cell responses to ancestral SARS‑CoV‑2 and Omicron variant among unvaccinated pregnant and postpartum women living with and without HIV in South Africa(Nature Research, 2024-09) Madhi, Shabir A.; McMahon, William C.; Kwatra, Gaurav; Izu, Alane; Jones, Stephanie A.; Mbele, Nkululeko J.; Jafta, Nwabisa; Lala, Rushil; Shalekof, Sharon; Tiemessen, Caroline T.; Nunes, Marta C.SARS-CoV-2 cell-mediated immunity remains understudied during pregnancy in unvaccinated Black African women living with HIV (WLWH) from low- and middle-income countries. We investigated SARS-CoV-2-specifc T-cell responses 1 month following infection in 24 HIV-uninfected women and 15 WLWH at any stage during pregnancy or postpartum. The full-length spike (FLS) glycoprotein and nucleocapsid (N) protein of wild-type (WT) SARS-CoV-2, as well as mutated spike protein regions found in the Omicron variant (B.1.1.529) were targeted by flow cytometry. WT-specific CD4+and CD8+T cells elicited similar FLS- and N-specific responses in HIV-uninfected women and WLWH. SARS-CoV 2-specifc T-lymphocytes were predominantly TNF-α monofunctional in pregnant and postpartum women living with and without HIV, with fever cells producing either IFN-γ or IL-2. Furthermore, T-cell responses were unaffected by Omicron-specific spike mutations as similar responses between Omicron and the ancestral virus were detected for CD4+ and CD8+ T cells. Our results collectively demonstrate comparable T-cell responses between WLWH on antiretroviral therapy and HIV-uninfected pregnant and postpartum women who were naïve to Covid-19 vaccination. Additionally, we show that T cells from women infected with the ancestral virus, Beta variant (B.1.351), or Delta variant (B.1.617.2) can cross-recognize Omicron, suggesting an overall preservation of T-cell immunity.Item Perceptions of counsellors and youth-serving professionals about sexual and reproductive health services for adolescents in Soweto, South Africa(BMC, 2018-02) Mulaudzi, Mamakiri; Dlamini, Busisiwe Nkala; Coetzee, Jenny; Sikkema, Kathleen; Gray, Glenda; Dietrich, Jana JanineBackground: Adolescents in South Africa remain vulnerable to HIV. Therefore, it is crucial to provide accessible adolescent-friendly HIV prevention interventions that are sensitive to their needs. This study aimed to investigate the perceptions of HIV counsellors and other youth-serving professionals about the barriers to providing adolescent youth-friendly sexual and reproductive health services to adolescents in Soweto, South Africa. The study also explored how sexual and reproductive health services in South Africa could be improved to become more accessible to adolescents. Methods: The research team conducted two focus group discussions with HIV counsellors, and 19 semi-structured interviews with youth-serving professionals from organisations working with adolescents. Audio-recorded data were transcribed verbatim and analysed using thematic analysis. Results: The results of the study reveal that counsellors were expected to give adolescents HIV counselling and testing (HCT) but felt restricted by what they perceived as inflexible standard operating procedures. Counsellors reported inadequate training to address adolescent psychosocial issues during HCT. Healthcare provider attitudes were perceived as a barrier to adolescents using sexual and reproductive health services. Participants strongly recommended augmenting adolescent sexual and reproductive health services to include counsellors and adolescents in developing age- and context-specific HIV prevention services for adolescents. Conclusion: Continuous upskilling of HIV counsellors is a critical step in providing adolescent-friendly services.Item Factors influencing access of pregnant women and their infants to their local healthcare system: a prospective, multicentre, observational study(BMC, 2018) Madhi, Shabir A.; Rivera, Luis M.; Sáez-Llorens, Xavier; Menéndez, Clara; Carrim-Ganey, Nazira; Cotton, Mark F.; Katzman, Darren; Luttig, Mariëtha M.; Candelario, Rosalba; Baker, Sherryl; Roychoudhury, MahuaBackground: The successful implementation of maternal vaccination relies on results of clinical trials, considering the prenatal and postnatal attendance at selected healthcare institutions. This study evaluated factors influencing maternal/infant access to healthcare facilities to identify potential barriers to participation in future clinical trials on maternal vaccination. Methods: In this prospective, multi-centre, observational study, pregnant women (N = 3243) were enrolled at ten sites across Panama, the Dominican Republic, South Africa, and Mozambique between 2012 and 2014. They completed questionnaires at enrolment, delivery, and infant follow-up (90 days post-partum) visits, including questions on transportation, phone accessibility, alternative childcare, gestational age at enrolment, delivery location, and health status of their infant. Logistic regression was used to identify factors significantly associated with return to study site for delivery or infant follow-up visits. Results: Among 3229 enrolled women with delivery information, 63.6% (range across sites: 25.3–91.5%) returned to study site for delivery. Older women and those at later gestational age at enrolment were more likely to deliver at the study site. While heterogeneities were observed at site level, shorter travel time at delivery and increased transportation costs at enrolment were associated with increased likelihood of women returning to study site for delivery. Among 3145 women with live-born infants, 3077 (95.3%) provided 90-day follow-up information; of these, 68.9% (range across sites: 25.6–98.9%) returned to study site for follow-up visits. Women with other children and with lower transportation costs at delivery were more likely to return to study site for follow-up visits. Among 666 infants reported sick, 94.3% were taken to a healthcare facility, with only 41.9% (range across sites: 4.9–77.3%) to the study site. Conclusion: Although high retention was observed from enrolment through 90 days after delivery, post-partum surveillance should be broadened beyond the study sites and additional follow-up visits should be planned within the neonatal period. The factors influencing maternal/infant access to healthcare facilities and the issues identified in this study should be taken into consideration in planning future clinical studies on maternal immunisation in low- and middle-income countries.Item Social health insurance contributes to universal coverage in South Africa, but generates inequities: survey among members of a government employee insurance scheme(BMC, 2018) Goudge, Jane; Harris, Bronwyn; Nxumalo, Nonhlanhla; Chersich, Matthew F.; Alaba, Olufunke A.; Govender, VeloshneeBackground: Many low- and middle-income countries are reforming their health financing mechanisms as part of broader strategies to achieve universal health coverage (UHC). Voluntary social health insurance, despite evidence of resulting inequities, is attractive to policy makers as it generates additional funds for health, and provides access to a greater range of benefits for the formally employed. The South African government introduced a voluntary health insurance scheme (GEMS) for government employees in 2005 with the aim of improving access to care and extending health coverage. In this paper we ask whether the new scheme has assisted in efforts to move towards UHC. Methods: Using a cross-sectional survey across four of South Africa’s nine provinces, we interviewed 1329 government employees, from the education and health sectors. Data were collected on socio-demographics, insurance coverage, health status and utilisation of health care. Multivariate logistic regression was used to determine if service utilisation was associated with insurance status. Results: A quarter of respondents remained uninsured, even higher among 20–29 year olds (46%) and lower-skilled employees (58%). In multivariate analysis, the odds of an outpatient visit and hospital admission for the uninsured was 0.3 fold that of the insured. Cross-subsidisation within the scheme has provided lower-paid civil servants with improved access to outpatient care at private facilities and chronic medication, where their outpatient (0.54 visits/ month) and inpatient utilisation (10.1%/year) approximates that of the overall population (29.4/month and 12.2% respectively). The scheme, however, generated inequities in utilisation among its members due to its differential benefit packages, with, for example, those with the most benefits having 1.0 outpatient visits/month compared to 0.6/ month with lowest benefits. Conclusions: By introducing the scheme, the government chose to prioritise access to private sector care for government employees, over improving the availability and quality of public sector services available to all. Government has recently regained its focus on achieving UHC through the public system, but is unlikely to discontinue GEMS, which is now firmly established. The inequities generated by the scheme have thus been institutionalised within the country’s financing system, and warrant attention. Raising scheme uptake and reducing differentials between benefit packages will ameliorate inequities within civil servants, but not across the country as a whole.Item Reagent‑free detection of Plasmodium falciparum malaria infections in feld‑collected mosquitoes using mid‑infrared spectroscopy and machine learning(Nature Research, 2024) Okumu, Fredos O.; Mwanga, Emmanuel P.; Kweyamba, Prisca A.; Siria, Doreen J.; Mshani, Issa H.; Mchola, Idrisa S.; Makala, Faraja E.; Seleman, Godian; Abbasi, Said; Mwinyi, Sophia H.; González‑Jiménez, Mario; Waynne, Klaas; Baldini, Francesco; Babayan, Simon A.Field-derived metrics are critical for efective control of malaria, particularly in sub-Saharan Africa where the disease kills over half a million people yearly. One key metric is entomological inoculation rate, a direct measure of transmission intensities, computed as a product of human biting rates and prevalence of Plasmodium sporozoites in mosquitoes. Unfortunately, current methods for identifying infectious mosquitoes are laborious, time consuming, and may require expensive reagents that are not always readily available. Here, we demonstrate the frst feld-application of mid-infrared spectroscopy and machine learning (MIRS-ML) to swiftly and accurately detect Plasmodium falciparum sporozoites in wild-caught Anopheles funestus, a major Afro-tropical malaria vector, without requiring any laboratory reagents. We collected 7178 female An. funestus from rural Tanzanian households using CDC-light traps, then desiccated and scanned their heads and thoraces using an FT-IR spectrometer. The porozoite infections were confrmed using enzyme-linked immunosorbent assay (ELISA) and polymerase chain reaction (PCR), to establish references for training supervised algorithms. The XGBoost model was used to detect sporozoite-infectious specimen, accurately predicting ELISA and PCR outcomes with 92% and 93% accuracies respectively. These fndings suggest that MIRS-ML can rapidly detect P. falciparum in feld-collected mosquitoes, with potential for enhancing surveillance in malaria-endemic regions. The technique is both fast, scanning 60–100 mosquitoes per hour, and cost-efcient, requiring no biochemical reactions and therefore no reagents. Given its previously proven capability in monitoring key entomological indicators like mosquito age, human blood index, and identities of vector species, we conclude that MIRS-ML could constitute a low-cost multi-functional toolkit for monitoring malaria risk and evaluating interventions.