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Background: The group of > 40 cryptic whitefly species called Bemisia tabaci sensu lato are amongst the world's worst agricultural pests and plant-virus vectors. Outbreaks of B. tabaci s.l. and the associated plant-virus diseases continue to contribute to global food insecurity and social instability, particularly in sub-Saharan Africa and Asia. Published B. tabaci s.l. genomes have limited use for studying African cassava B. tabaci SSA1 species, due to the high genetic divergences between them. Genomic annotations presented here were performed using the 'Ensembl gene annotation system', to ensure that comparative analyses and conclusions reflect biological differences, as opposed to arising from different methodologies underpinning transcript model identification., Results: We present here six new B. tabaci s.l. genomes from Africa and Asia, and two re-annotated previously published genomes, to provide evolutionary insights into these globally distributed pests. Genome sizes ranged between 616-658 Mb and exhibited some of the highest coverage of transposable elements reported within Arthropoda. Many fewer total protein coding genes (PCG) were recovered compared to the previously published B. tabaci s.l. genomes and structural annotations generated via the uniform methodology strongly supported a repertoire of between 12.8-13.2 × 10 3 PCG. An integrative systematics approach incorporating phylogenomic analysis of nuclear and mitochondrial markers supported a monophyletic Aleyrodidae and the basal positioning of B. tabaci Uganda-1 to the sub-Saharan group of species. Reciprocal cross-mating data and the co-cladogenesis pattern of the primary obligate endosymbiont 'Candidatus Portiera aleyrodidarum' from 11 Bemisia genomes further supported the phylogenetic reconstruction to show that African cassava B. tabaci populations consist of just three biological species. We include comparative analyses of gene families related to detoxification, sugar metabolism, vector competency and evaluate the presence and function of horizontally transferred genes, essential for understanding the evolution and unique biology of constituent B. tabaci. s.l species., Conclusions: These genomic resources have provided new and critical insights into the genetics underlying B. tabaci s.l. biology. They also provide a rich foundation for post-genomic research, including the selection of candidate gene-targets for innovative whitefly and virus-control strategies., (© 2023. The Author(s).)

Background: The novel anti-malarial cipargamin (KAE609) has potent, rapid activity against Plasmodium falciparum. Transient asymptomatic liver function test elevations were previously observed in cipargamin-treated subjects in two trials: one in malaria patients in Asia and one in volunteers with experimentally induced malaria. In this study, the hepatic safety of cipargamin given as single doses of 10 to 150 mg and 10 to 50 mg once daily for 3 days was assessed. Efficacy results, frequency of treatment-emerging mutations in the atp4 gene and pharmacokinetics have been published elsewhere. Further, the R561H mutation in the k13 gene, which confers artemisinin-resistance, was associated with delayed parasite clearance following treatment with artemether-lumefantrine in Rwanda in this study. This was also the first study with cipargamin to be conducted in patients in sub-Saharan Africa., Methods: This was a Phase II, multicentre, randomized, open-label, dose-escalation trial in adults with uncomplicated falciparum malaria in five sub-Saharan countries, using artemether-lumefantrine as control. The primary endpoint was ≥ 2 Common Terminology Criteria for Adverse Events (CTCAE) Grade increase from baseline in alanine aminotransferase (ALT) or aspartate transaminase (AST) during the 4-week trial., Results: Overall, 2/135 patients treated with cipargamin had ≥ 2 CTCAE Grade increases from baseline in ALT or AST compared to 2/51 artemether-lumefantrine patients, with no significant difference between any cipargamin treatment group and the control group. Cipargamin exposure was comparable to or higher than those in previous studies. Hepatic adverse events and general safety and tolerability were similar for all cipargamin doses and artemether-lumefantrine. Cipargamin was well tolerated with no safety concerns., Conclusions: This active-controlled, dose escalation study was a detailed assessment of the hepatic safety of cipargamin, across a wide range of doses, in patients with uncomplicated falciparum malaria. Comparison with previous cipargamin trials requires caution as no clear conclusion can be drawn as to whether hepatic safety and potential immunity to malaria would differ with ethnicity, patient age and or geography. Previous concerns regarding hepatic safety may have been confounded by factors including malaria itself, whether natural or experimental infection, and should not limit the further development of cipargamin. Trial registration ClinicalTrials.gov number: NCT03334747 (7 Nov 2017), other study ID CKAE609A2202., (© 2021. The Author(s).)

Introduction: Failure on second-line antiretroviral therapy (ART) with protease inhibitor (PI) mutations (VF-M) is on the rise. However, there is a paucity of information on the factors associated with this observation in low-income countries. Knowledge of underlying factors is critical if we are to minimize the number of PLHIV switched to costly third-line ART. Our study investigated the factors associated with VF-M., Methods: We conducted a matched case-control analysis of patients' records kept at the Joint Clinical Research Center, starting from January 2008 to May 2018. We matched records of patients who failed the second-line ART with major PI mutations (cases) with records of patients who were virologically suppressed (controls) by a ratio of 1:3. Data analysis was conducted using STATA Version 14. Categorical variables were compared with the outcomes failure on second-line ART with PI mutations using the Chi-square and Fisher's exact tests where appropriate. Conditional logistic regression for paired data was used to assess the association between the outcome and exposure variables, employing the backward model building procedure., Results: Of the 340 reviewed patients' records, 53% were women, and 6.2% had previous tuberculosis treatment. Males (aOR = 2.58, [CI 1.42-4.69]), and patients concurrently on tuberculosis treatment while on second-line ART (aOR = 5.65, [CI 1.76-18.09]) had higher odds of VF-M. ART initiation between 2001 and 2015 had lower odds of VF-M relative to initiation before the year 2001., Conclusion: Males and patients concomitantly on tuberculosis treatment while on second-line ART are at a higher risk of VF-M. HIV/AIDS response programs should give special attention to this group of people if we are to minimize the need for expensive third-line ART. We recommend more extensive, explorative studies to ascertain underlying factors.

Background: Uganda's Ministry of Health registered a 12% increase in new Tuberculosis (TB) cases between 2001 and 2005. Of these, 20% were from Kampala district and most from Mulago national referral hospital where the largest and the oldest medical school is found. Medical students are likely to have an increased exposure to TB infection due to their training in hospitals compared to other university students. The study compared the prevalence of TB infection and associated factors among undergraduate medical and veterinary students in Makerere University, Uganda., Methods: This was a cross-sectional study with 232 medical and 250 veterinary undergraduate students. Socio-demographic and past medical history data was collected using questionnaires. A tuberculin skin test was performed on the volar aspect of the left forearm. An induration ≥10 mm in diameter after 48-72 hrs was considered positive. Logistic regression was used to determine association of independent variables with TB infection., Results: The prevalence of TB infection was higher in medical students (44.8%, 95% C.I= 38.4-51.3%) compared to veterinary students (35.2%, 95% C.I = 29.3-41.1%). The significant predictors of TB infection were: being a medical student (aOR=1.56, 95% CI = 1.05-2.31), male sex (aOR=1.75, 95% CI = 1.17-2.63), history of contact with a confirmed TB case (aOR=1.57, 95% CI = 1.06-2.31) and residing at home (aOR=2.08, 95% CI = 1.20-3.61). Among the medical students, having gone to a day compared to boarding high school (aOR=2.31, 95% CI = 1.06-5.04), involvement in extracurricular clinical exposure (aOR=3.39 95% CI = 1.60-7.16), male sex, residence at home, and history of contact with a TB case predicted TB infection., Conclusion: Medical students have a higher prevalence of TB infection than veterinary students probably due to increased exposure during training. There is a need to emphasize TB infection control measures in hospitals and the general community.