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Background Few studies have evaluated tuberculosis control in children and adolescents. We used routine tuberculosis surveillance data to quantify age- and human immunodeficiency virus (HIV)-stratified trends over time and investigate the relationship between tuberculosis, HIV, age, and sex. Methods All children and adolescents (0–19 years) routinely treated for drug-susceptible tuberculosis in South Africa and recorded in a de-duplicated national electronic tuberculosis treatment register (2004–2016) were included. Age- and HIV-stratified tuberculosis case notification rates (CNRs) were calculated in four age bands: 0–4, 5–9, 10–14, and 15–19 years. The association between HIV infection, age, and sex in children and adolescents with tuberculosis was evaluated using multivariable logistic regression. Results Of 719 400 children and adolescents included, 339 112 (47%) were 0–4 year olds. The overall tuberculosis CNR for 0–19 year olds declined by 54% between 2009 and 2016 (incidence rate ratio [IRR] = 0.46; 95% confidence interval [CI],.45–.47). Trends varied by age and HIV, with the smallest reductions (2013–2016) in HIV-positive 0–4 year olds (IRR = 0.90; 95% CI,.85–.95) and both HIV-positive (IRR = .84; 95% CI,.80–.88) and HIV-negative (IRR = 0.89; 95% CI,.86–.92) 15–19 year olds. Compared with 0- to 4-year-old males, odds of HIV coinfection among 15–19 year olds were nearly twice as high in females (adjusted odds ratio [aOR] = 2.49; 95% CI, 2.38–2.60) than in males (aOR = 1.35; 95% CI, 1.29–1.42). Conclusions South Africa's national response to the HIV epidemic has made a substantial contribution to the observed declining trends in tuberculosis CNRs in children and adolescents. The slow decline of tuberculosis CNRs in adolescents and young HIV-positive children is concerning. Understanding how tuberculosis affects children and adolescents beyond conventional age bands and by sex can inform targeted tuberculosis control strategies. [ABSTRACT FROM AUTHOR]

In a context of water scarcity, efforts to increase landscape production should focus on improving water productivity. This requires an appreciation of the various components of evapotranspiration (ET), including soil evaporation (Es) because the latter reflects 'unproductive' water loss. Both complex and simple algorithms have been developed to determine ET. In data scarce areas, developing and testing parsimonious algorithms is useful. This study sought to improve a simple single layer ET model by incorporating an Es component. Empirical methods were also explored to predict ET from vegetation indices (VIs), leaf area index (LAI) and reference evapotranspiration (ET0). A large aperture scintillometer and an eddy covariance (EC) system were used to validate the proposed algorithm at three sites over Grasslands and Albany Thicket biomes in the Eastern Cape, South Africa. There was good agreement between the observed and predicted ET with RMSE of 0.30-0.58 mm d−1 when average daily observed ET was 0.43-3.24 mm. The VIs had moderate correlations with the observed data due to the significant role played by Es (65%-84%) across the sites and stomatal conductance at the Albany Thicket site. The simple algorithms developed would make determining ET easier in data scarce regions. [ABSTRACT FROM AUTHOR]