Browsing by Subject "Southern Africa"

Now showing 1 - 3 of 3
  • Thumbnail Image
    Item
    A historical perspective on arboviruses of public health interest in Southern Africa
    (Taylor & Francis, 2024) Hungwe, Faith T. T.; Laycock, Katherine M.; Ntereke, Tlhalefo D.; Mabaka, Rorisang; Paganotti, Giacomo M.; Pediatrics, School of Medicine
    Arboviruses are an existing and expanding threat globally, with the potential for causing devastating health and socioeconomic impacts. Mitigating this threat necessitates a One Health approach that integrates vector surveillance, rapid disease detection, and innovative prevention and control measures. In Southern Africa, limited data on the epidemiology of arboviruses, their vectors, and their hosts prevent an effective response. We reviewed the current knowledge on arboviruses in Southern Africa and identified opportunities for further research. A literature search was conducted to identify studies published on arboviruses in 10 tropical and temperate countries of the Southern African Development Community (SADC) from 1900 onward. We identified 280 studies, half (51.1%) originating from South Africa, that described 31 arboviral species, their vectors, and their clinical effects on hosts reported in the region. Arboviral research flourished in the SADC in the mid-20th century but then declined, before reemerging in the last two decades. Recent research consists largely of case reports describing outbreaks. Historical vector surveillance and serosurveys from the mid-20th century suggest that arboviruses are plentiful across Southern Africa, but large gaps remain in the current understanding of arboviral distribution, transmission dynamics, and public health impact.
  • Thumbnail Image
    Item
    High Unreported Mortality in Children and Youth (<25 Years) Living With HIV Who Were Lost to Care From Antiretroviral Therapy Programs in Southern Africa: Results From a Multicountry Tracing Study
    (Wolters Kluwer, 2022-12-15) Nyakato, Patience; Christ, Benedikt; Anderegg, Nanina; Muhairwe, Josephine; Jefferys, Laura; van Dijk, Janneke; Vinikoor, Michael J.; van Lettow, Monique; Chimbetete, Cleophas; Phiri, Sam J.; Egger, Matthias; Ballif, Marie; Yiannoutsos, Constantin T.; Schomaker, Michael; Kassanjee, Reshma; Davies, Mary-Ann; Cornell, Morna; International epidemiology Databases to Evaluate AIDS Southern Africa (IeDEA-SA); Biostatistics and Health Data Science, Richard M. Fairbanks School of Public Health
    Background: Antiretroviral therapy program mortality maybe underestimated if deceased patients are misclassified as lost. Methods: We used two-stage inverse probability weighting to account for probability of being: sampled for tracing and found by the tracer. Results: Among 680 children and youth aged <25 years on antiretroviral therapy who were lost and traced in Southern Africa between October 2017 and November 2019, estimated mortality was high at 9.1% (62/680). After adjusting for measured covariates and within-site clustering, mortality remained lower for young adults aged 20–24 years compared with infants aged <2 years [adjusted hazard ratio: 0.40 (95% confidence interval: 0.31 to 0.51)]. Conclusions: Our study confirms high unreported mortality in children and youth who are lost and the need for tracing to assess vital status among those who are lost to accurately report on program mortality.
  • Thumbnail Image
    Item
    Virologic response of adolescents living with perinatally acquired HIV receiving antiretroviral therapy in the period of early adolescence (10-14 years) in South Africa
    (Wolters Kluwer, 2021) Nyakato, Patience; Schomaker, Michael; Sipambo, Nosisa; Technau, Karl-Günter; Fatti, Geoffrey; Rabie, Helena; Tanser, Frank; Eley, Brian; Euvrard, Jonathan; Wood, Robin; Tsondai, Priscilla R.; Yiannoutsos, Constantin T.; Cornell, Morna; Davies, Mary-Ann; Biostatistics and Health Data Science, Richard M. Fairbanks School of Public Health
    Background and objectives: Adolescents living with perinatally acquired HIV (ALPHIV) on antiretroviral therapy (ART) have been noted to have poorer adherence, retention and virologic control compared to adolescents with non-perinatally acquired HIV, children or adults. We aimed to describe and examine factors associated with longitudinal virologic response during early adolescence. Design: A retrospective cohort study. Methods: We included ALPHIV who initiated ART before age 9.5 years in South African cohorts of the International epidemiology Database to Evaluate AIDS-Southern Africa (IeDEA-SA) collaboration (2004-2016); with viral load (VL) values <400 copies/ml at age 10 years and at least one VL measurement after age 10 years. We used a log-linear quantile mixed model to assess factors associated with elevated (75th quantile) VLs. Results: We included 4396 ALPHIV, 50.7% were male, with median (interquartile range) age at ART start of 6.5 (4.5, 8.1) years. Of these, 74.9% were on a non-nucleoside reverse transcriptase inhibitor (NNRTI) at age 10 years. After adjusting for other patient characteristics, the 75th quantile VLs increased with increasing age being 3.13-fold (95% CI 2.66, 3.68) higher at age 14 versus age 10, were 3.25-fold (95% CI 2.81, 3.75) higher for patients on second-line protease-inhibitor and 1.81-fold for second-line NNRTI-based regimens (versus first-line NNRTI-based regimens). There was no difference by sex. Conclusions: As adolescents age between 10 and 14 years, they are increasingly likely to experience higher VL values, particularly if receiving second-line protease inhibitor or NNRTI-based regimens, which warrant adherence support interventions.