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Browsing by Author "Lessells, Richard John."

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    Dolutegravir for first-line antiretroviral therapy in low-income and middle-income countries: uncertainties and opportunities for implementation and research.
    (Elsevier., 2018) Dorward, Jienchi.; Lessells, Richard John.; Drain, Paul K.; Naidoo, Kogieleum.; De Oliveira, Tulio De Paiva Nazareth Andrade.; Pillay, Yogan.; Abdool Karim, Salim Safurdeen.; Garrett, Nigel Joel.
    Abstract available in pdf.
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    Implementation of an efficient sample pooling strategy for high throughput diagnostic testing of Severe Acute Respiratory Syndrome Corona Virus-2.
    (2022) Anyaneji, Ugochukwu Jacob.; De Oliveira, Tulio Paiva N Andrade.; Petruccione, Francesco.; Giandhari, Jennifer.; Lessells, Richard John.; Singh, Lavanya.
    The rapid identification and isolation of infected individuals remains a key strategy for controlling the spread of SARS-CoV-2. Frequent testing of populations to detect infection early in asymptomatic or presymptomatic individuals can be a powerful tool for intercepting transmission, especially when the viral prevalence is low. However, RT-PCR testing – the gold standard of SARS-CoV-2 diagnosis – is expensive, making regular testing of every individual unfeasible. Sample pooling is one approach to lowering costs. By combining samples and testing them in groups the number of tests required is reduced, substantially lowering costs. Here we report on the implementation of pooling strategies using 3-d and 4-d hypercubes to test a professional sports team in South Africa. We have shown that infected samples can be reliably detected in groups of 27 and 81, with minimal loss of assay sensitivity for samples with individual Ct values of up to 32. We report on the automation of sample pooling, using a liquid-handling robot and an automated web interface to identify positive samples. We conclude that hypercube pooling allows for the reliable RT-PCR detection of SARS-CoV-2 infection, at significantly lower costs than lateral flow antigen tests.
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    Moderate-to-high levels of pretreatment HIV drug resistance in KwaZulu-Natal Province, South Africa.
    (Mary Ann Liebert., 2019) Chimukangara, Benjamin.; Naidoo, Kogieleum.; Rhee, Soo-Yon.; Manasa, Justen.; Gräf, Tiago.; Lewis, Lara.; Cawood, Cherie.; Khanyile, David.; Diallo, Karidia.; Ayalew, Kassahun A.; Shafer, Robert W.; Hunt, Gillian.; Pillay, Deenan.; De Oliveira, Tulio De Paiva Nazareth Andrade.; Abdool Karim, Salim Safurdeen.; Lessells, Richard John.; Kharsany, Ayesha Bibi Mahomed.
    Abstract available in PDF.