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Objectives: The predominance of Bantu languages in sub‐Saharan Africa has sparked a large debate over the processes through which they came to disperse over time and space—the "Bantu expansion." The overall genetic similarity shown by Bantu‐speaking populations indicates that movement of people occurred too, but the extent of the correlation between genetics, linguistics and geography has been a matter of debate among scholars of different disciplines. In this work, we aim to investigate how genetic, linguistic and geographic distances relate to each other in Bantu‐speaking populations. Methods: We analyzed genome‐wide SNP array data from a set of 37 Bantu and non‐Bantu‐speaking populations together with related linguistic and geographic data. Due to the complex demographic relationships resulting from events of admixture in the history of these populations, we develop and implement a method for controlling the signatures of admixture. Results: Genetic distances were only minimally correlated with linguistic and geographic distances, possibly as the result of gene flow from neighboring groups into Bantu‐speaking populations. When signatures of admixture are controlled for, the correlation of genetic data with linguistic and geographic distances significantly increases. Discussion: The increase of the correlation between linguistic and genetic distances after the signatures of admixture are taken into account is in agreement with a scenario of spatial co‐dispersal of languages and people. Additional specific cultural and demographic dynamics have probably further affected the relationship between language and genetics, which will be necessary to take into account when integrating multidisciplinary data to reconstruct the history of populations. [ABSTRACT FROM AUTHOR]

Introduction: Viral load testing is essential to manage HIV disease, especially in infants and children. Early infant diagnosis is performed using nucleic‐acid testing in children under 18 months. Resource‐limited health systems face severe challenges to scale‐up both viral load and early infant diagnosis to unprecedented levels. Streamlining laboratory systems would be beneficial to improve access to quality testing and to increase efficiency of antiretroviral treatment programmes. We evaluated the performance of viral load testing to serve as an early infant diagnosis assay in children younger than 18 months. Methods: This study was an observational, prospective study, including children between one and 18 months of age who were born to HIV‐positive mothers in 134 health facilities in Maputo City and Maputo Province, Mozambique. Dried blood spot specimens from heel or toe pricks were collected between January and April 2018, processed using SPEX buffer for both assays, and tested for routine EID and VL testing using the Roche CAP/CTM HIV‐1 Qualitative v2 and Roche CAP/CTM HIV‐1 Quantitative v2 assays respectively. The sensitivity, specificity and positive and negative predictive values were estimated using the EID results as the reference standard. Results: A total of 1021 infants were included in the study, of which 47% were female. Over 95% of mothers and children were on antiretroviral treatment or received antiretroviral prophylaxis respectively. The sensitivity and specificity of using the viral load assay to detect infection were 100% (95% CI: 96.2 to 100%) and 99.9% (95% CI: 99.4 to 100%). The positive and negative predictive values were 99.0% (95% CI: 94.3 to 100%) and 100% (95% CI: 99.6 to 100%). The McNemar's test was 1.000 and Cohen's kappa was 0.994. Conclusions: The comparable performance suggests that viral load assays can be used as an infant diagnostic assay. Infants with either low levels of viraemia or high cycle threshold values should be repeat tested to ensure the result is truly positive prior to treatment initiation, regardless of assay used. Viral load assays could replace traditional early infant diagnosis testing, substantially streamlining molecular laboratory services for children and lowering costs, with the additional advantage of providing baseline viral load results for antiretroviral treatment management. [ABSTRACT FROM AUTHOR]