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Abstract Background The COVID-19 pandemic had a profound impact on healthcare and ophthalmology services globally. Numerous studies amongst various medical and surgical specialties showed a reduction in patient attendance and surgical procedures performed. Prior published ophthalmic literature focused on specific types of procedures and were usually single centre. The current study attempts to quantify the impact on a larger scale, namely that of sub-Saharan Africa, and to include all ophthalmic subspecialties. Methods This is a retrospective analysis of the surgical records from 17 ophthalmology centres in seven countries located in East, Central, West and Southern Africa. The date of declaration of the first lockdown was used as the beginning of the pandemic and the pivot point to compare theatre records one year prior to the pandemic and the first year of the pandemic. We examined the total number of surgical procedures over the two year period and categorized them according to ophthalmic subspecialty and type of procedure performed. We then compared the pre-pandemic and pandemic surgical numbers over the two year period. Results There were 26,357 ophthalmic surgical procedures performed with a significant decrease in the first year of the pandemic (n = 8942) compared to the year prior to the pandemic (n = 17,415). The number of surgical procedures performed was lower in the first year of the pandemic compared to the year prior to the pandemic by 49% [Incidence rate ratio (IRR) 0.51, 95% CI 0.41–0.64), 27% (0.73, 0.55–0.99), 46% (0.54, 0.30–0.99), 40% (0.60, 0.39–0.92) and 59% (0.41, 0.29–0.57) in sub-Saharan Africa (4 regions combined), West, Central, East and Southern Africa, respectively]. The number of surgical procedures in the different sub-specialty categories in sub-Saharan Africa (4 regions combined) was significantly lower in the first year of the pandemic compared to the year prior to the pandemic, except for glaucoma (IRR 0.72, 95% CI 0.52–1.01), oncology (0.71, 0.48–1.05), trauma (0.90, 0.63–1.28) and vitreoretinal (0.67, 0.42–1.08) categories. Conclusion This study provides insight into the impact of the COVID-19 pandemic in multiple regions and countries on the African continent. The identification of which surgical subspecialty was most affected by the COVID-19 pandemic in each region allows for better planning and resource allocation to address these backlogs.

Background: Background: Despite nearly twenty years of an effective vaccine, hepatitis B remains one of the most common viral infections worldwide. Mother-to-child transmission is a major route in children. Objective: to evaluate HBV-infected mothers’ children’s vaccination response. Methods: The Centre Hospitalier Dominicain St-Martin de Porres, Yaounde prenatal care (ANC) database included HBsAg-positive consenting women and their children. Social demographics were acquired using a tested questionnaire. The 5 hepatitis B indicators were evaluated and anti-HBsAg antibodies quantified by indirect ELISA. Microsoft Excel and Epi-info was used to examine data. Results. Out of 5,996 women registered, 143 were HBsAg positive (2.38% prevalence) and none were HBeAg positive. Of 143 HBsAgpositive women, 50 participated in the study. Out of 50 positive moms, 78 children were included, with a mean age ± SD of 2.33 ± 2.86 years. None of the children were infected with HBV, but all were exposed. 64 (82.05%) received anti-HBs immunoglobulin (HBIG) and a vaccine at birth, while 14 (17.95%) received only the vaccine. 72 (92.31%) children received all three vaccination doses. The vaccine responders were 62.82% (above 10 IU/mL), while 37.18% of children were nonresponders, a greater risk group if not supplemented. Conclusion: This study found 92.31% child anti-HBV immunization coverage. WHO recommends 95% protection, but 62.82% is below that. The causes of this poor protection should be examined.

Background: HIV case finding is an essential component for ending AIDS, but there is limited evidence on the effectiveness of such a strategy in the pediatric population. We sought to determine HIV positivity rates among children according to entry points in Cameroon. Methods: A facility-based survey was conducted from January 2015 to December 2019 among mother–child couples at various entry points of health facilities in six regions of Cameroon. A questionnaire was administered to parents/guardians. Children were tested by polymerase chain reaction (PCR). Positivity rates were compared between entry points. Associations were quantified using the unadjusted positivity ratio (PR) for univariate analyses and the adjusted positivity ratio (aPR) for multiple Poisson regression analyses with 95% confidence intervals (CIs). p-values < 0.05 were considered significant. Results: Overall, 24,097 children were enrolled. Among them, 75.91% were tested through the HIV prevention of mother-to-child transmission (PMTCT) program, followed by outpatient (13.27%) and immunization (6.27%) services. In total, PMTCT, immunization, and outpatient services accounted for 95.39% of children. The overall positivity was 5.71%, with significant differences (p < 0.001) between entry points. Univariate analysis showed that inpatient service (PR = 1.45; 95% CI: [1.08, 1.94]; p = 0.014), infant welfare (PR = 0.43; 95% CI: [0.28, 0.66]; p < 0.001), immunization (PR = 0.56; 95% CI: [0.45, 0.70]; p < 0.001), and PMTCT (PR = 0.41; 95% CI: [0.37, 0.46]; p < 0.001) were associated with HIV transmission. After adjusting for other covariates, only PMTCT was associated with transmission (aPR = 0.66; 95% CI: [0.51, 0.86]; p = 0.002). Conclusions: While PMTCT accounts for most tested children, high HIV positivity rates were found among children presenting at inpatient, nutrition, and outpatient services and HIV care units. Thus, systematic HIV testing should be proposed for all sick children presenting at the hospital who have escaped the PMTCT cascade.

Microbial communities play an important role in the fitness of mosquito hosts. However, the factors shaping microbial communities in wild populations, with regard to interactions among microbial species, are still largely unknown. Previous research has demonstrated that two of the most studied mosquito symbionts, the bacteria Wolbachia and Asaia, seem to compete or not compete, depending on the genetic background of the reference mosquito host. The large diversity of Wolbachia–Asaia strain combinations that infect natural populations of mosquitoes may offer a relevant opportunity to select suitable phenotypes for the suppression of pathogen transmission and for the manipulation of host reproduction. We surveyed Wolbachia and Asaia in 44 mosquito populations belonging to 11 different species of the genera Anopheles, Aedes, and Culex using qualitative PCR. Through quantitative PCR, the amounts of both bacteria were assessed in different mosquito organs, and through metagenomics, we determined the microbiota compositions in some selected mosquito populations. We show that variation in microbial community structure is likely associated with the species/strain of mosquito, its geographical position, and tissue localization. Together, our results shed light on the interactions among different bacterial species in the microbial communities of mosquito vectors, and this can aid the development and/or improvement of methods for symbiotic control of insect vectors.

Introduction The success of antiretroviral therapy (ART) has changed HIV from a deadly to a chronic infection, thus increasing the transitioning from infancy toward adulthood. However, the virostatic nature of antiretrovirals maintains viruses in sanctuaries, with reactivation potentials. Because current ARTs are very limited for children, the emergence of new HIV epidemics driven by HIV drug-resistance mutations is favoured. Our systematic review aims to estimate the global burden of archived drug-resistance mutations (ADRMs) and the size of reservoir (HIV-1 DNA load), and their associated factors in children and adolescents.Methods and analysis Papers from the PubMed/MEDLINE, Google Scholar, ScienceDirect, African Journals Online and Academic Medical Education Databases will be systematically identified using the keywords: “HIV-1 reservoirs”, “viral reservoirs”, “HIV-1 DNA”, infants, adolescents, child and children, linked by the following Boolean operators: ‘OR’ and ‘AND’. Randomised and non-randomised trials, cohort studies and cross-sectional studies published in French or English from January 2002 will be included, while case reports, letters, comments, reviews, systematic reviews and meta-analyses, and editorials will be excluded. All studies describing data on ADRMs, HIV-1 DNA load and/or immunological markers among children/adolescents will be eligible. A random-effects model will be used to calculate the pooled prevalence of ADRMs. Data will be reported according to type of viral reservoir (peripheral blood mononuclear cells, CD4 cells), geographical location (country/continent), ethnicity/race, age (infants vs adolescents), gender, HIV-1 clades, ART exposure (naïve vs treated, drug class, type of regimen, age at ART initiation and treatment duration), WHO clinical staging (I, II, III, IV), immune status (immune compromised vs immune competent) and virological response (viraemic vs non-viraemic). Multivariate logistic regression will be performed to determine predictors of HIV reservoir profile in paediatric populations. The primary outcome will be to assess the genotypical and quantitative profile of HIV reservoirs, while the secondary outcomes will be to identify factors associated with ADRMs and reservoir size in paediatric populations.Ethics and dissemination Ethical approval is not applicable for this study as it will be based on published data. Results will be disseminated via a peer-reviewed scientific journal and relevant conferences.PROSPERO registration number CRD42022327625.

Antiretroviral therapy (ART) has improved the lifespan of people living with HIV. However, their immune system remains in a state of sustained activation/inflammation, which favors viral replication and depletion of helper T-cells with varying profiles according to ART-response. We herein sought to ascertain the inflammatory profile of adolescents living with perinatal HIV-1 infection (ALPHI) receiving ART in an African context. In this cross-sectional and comparative study among ART-experienced ALPHI in Yaoundé-Cameroon, HIV-1 RNA was measured by Abbott Real-time PCR; CD4 cells were enumerated using flow cytometry; serum cytokines were measured by ELISA; HIV-1 proviral DNA was genotyped by Sanger-sequencing; and archived drug resistance mutations (ADRMs) were interpreted using Stanford HIVdb.v9.0.1. Overall, 73 adolescents were enrolled (60 ALPHI and 13 HIV-1 negative peers) aged 15 (13-18) years; 60.00% were female. ART median duration was 92 (46-123) months; median viral load was 3.99 (3.17-4.66) RNA Log10 (copies)/mL and median CD4 count was 326 (201-654) cells/mm3. As compared to HIV-negative adolescents, TNFα was highly expressed among ALPHI (p

This article provides a birds-eye view on the role of decision trees in machine learning and data science over roughly four decades. It sketches the evolution of decision tree research over the years, describes the broader context in which the research is situated, and summarizes strengths and weaknesses of decision trees in this context. The main goal of the article is to clarify the broad relevance to machine learning and artificial intelligence, both practical and theoretical, that decision trees still have today.

About 90% of new HIV-1 infections in children occur in sub-Saharan Africa, where treatment monitoring remains suboptimal. We sought to ascertain factors associated with immunovirological responses among an ART-experienced paediatric population in Cameroon. A laboratory-based and analytical study was conducted from January 2017 throughout December 2020 wherein plasma viral load (PVL) analyses and CD4 cell counts were performed. Viral suppression (VS) was defined as PVL < 1000 copies/mL and immunological failure (IF) as CD4 < 500 cells/µL for participants ≤5 years and CD4 < 250 cells/µL for those >5 years; p < 0.05 was considered statistically significant. Overall, 272 participants were enrolled (median age: 13 [9–15.5] years; 54% males); median ART duration 7 [3–10] years. Globally, VS was achieved in 54.41%. VS was 56.96% in urban versus 40.48% in rural areas (p = 0.04). IF was 22.43%, with 15.79% among participants ≤5 years and 22.92% among those >5 years (p = 0.66). IF was 20.43% in urban versus 33.33% in rural areas (p = 0.10). Following ART, IF was 25.82% on first-line (non-nucleoside reverse transcriptase inhibitors; NNRTI-based) versus 10.17% on second-line (protease inhibitor-based) regimens (p = 0.01). Interestingly, IF was 7.43% among virally suppressed versus 40.32% among virally unsuppressed participants (p < 0.0001). A low VS indicates major challenges in achieving AIDS’ elimination in this paediatric population, especially in rural settings and poor immune statuses. Scaling up NNRTI-sparing regimens alongside close monitoring would ensure optimal therapeutic outcomes.

Introduction: Determining the HIV status of some individuals remains challenging due to multidimensional factors such as flaws in diagnostic systems, technological challenges, and viral diversity. This report pinpoints challenges faced by the HIV testing system in Cameroon. Case presentation: A 53-year-old male received a positive HIV result by a rapid testing algorithm in July 2016. Not convinced of his HIV status, he requested additional tests. In February 2017, he received a positive result using ImmunoComb® II HIV 1 2 BiSpot and Roche cobas electrochemiluminescence assays. A sample sent to France in April 2017 was positive on the Bio-Rad GenScreen™ HIV 1/2, but serotyping was indeterminate, and viral load was 20 copies/mL. The Roche electrochemiluminescence immunoassay and INNO-LIA HIV I/II Score were negative for samples collected in 2018. A sample collected in July 2019 and tested with VIDAS® HIV Duo Ultra enzyme-linked fluorescent assay and Geenius™ HIV 1/2 Confirmatory Assay was positive, but negative with Western blot; CD4 count was 1380 cells/mm3 and HIV proviral DNA tested in France was ‘target-not-detected’. Some rapid tests were still positive in 2020 and 2021. Serotyping remained indeterminate, and viral load was ‘target-not-detected’. There were no self-reported exposure to HIV risk factors, and his wife was HIV-seronegative. Management and outcome: Given that the patient remained asymptomatic with no evidence of viral replication, no antiretroviral therapy was initiated. Conclusion: This case highlights the struggles faced by some individuals in confirming their HIV status and the need to update existing technologies and develop an algorithm for managing exceptional cases.

BackgroundThe mother-to-child transmission of HIV-1 (MTCT) remains on the major route of HIV-transmission among pediatric populations in Africa. Though a prevention of MTCT (PMTCT) high-priority country, data on the MTCT burdens in Cameroon remains fragmented.ObjectiveWe sought to assess the pooled MTCT rate, its risk-factors, and to characterize viral reservoirs of infected-children in Cameroon.MethodsAll relevant observational cohort and cross-sectional studies conducted in Cameroon were searched from PubMed, African Journals Online, Google scholar, ScienceDirect and academic medical education databases. Heterogeneity and publication bias were respectively assessed by the I2 statistic and the Egger/funnel plot test. Meta-analysis was performed using the random effects model. MTCT rate >5% was considered as "high". This review was registered in the Prospero database, CRD42021224497.ResultsWe included a total of 29 studies and analyzed 46 684 children born from HIV-positive mothers. The overall rate of MTCT was 7.00% (95% CI = 6.07-8.51). According to regions, the highest burden was in Adamaoua-region (17.51% [95% CI:14.21-21.07]) with only one study found. PMTCT option-B+ resulted in about 25% reduction of MTCT (8.97% [95% CI: 8.71-9.24] without option-B+ versus 2.88% [95% CI: 5.03-9.34] with option-B+). Regarding risk-factors, MTCT was significantly associated with the absence of PMTCT-interventions both in children (OR:5.40 [95% CI: 2.58-11.27]) and mothers (OR: 3.59 [95% CI: 2.15-5.99]). Regarding viral reservoirs, a pro-viral DNA mean of 3.34±1.05 log10/mL was observed among 5/57 children and archived HIV drug resistance mutations were identified in pro-viral DNA marker among 21/79 infected-children.ConclusionIn spite of the dropdown in MTCT following option-B+ implementation, MTCT remains high in Cameroon, with substantial disparities across regions. Thus, in this era of option-B+, achieving MTCT elimination requires interventions in northern-Cameroon. The variation in pro-viral load in infected-children underlines the relevance of characterizing viral reservoirs for possible infection control in tropical settings.

BackgroundAntiretroviral therapy (ART) can bring HIV-1 levels in blood plasma to the undetectable level and allow a near-normal life expectancy for HIV-infected individuals. Unfortunately, ART is not curative and must be taken for life, because within a few weeks of treatment cessation, HIV viremia rebounds in most patients except for rare elite or posttreatment controllers of viremia. The primary source of this rebound is the highly stable reservoir of latent yet replication-competent HIV-1 proviruses integrated into the genomic DNA of the resting memory cluster of differentiation 4 (CD4+) T cells. To achieve a cure for HIV, understanding the cell reservoir environment is of paramount importance. The size and nature of the viral reservoir might vary according to the timing of therapy, therapeutic response, ART duration, and immune response. The mechanisms of reservoir maintenance generally depend on the levels/type of immune recognition; in addition, the dynamics of viral persistence are different between pediatric and adult populations. This difference could become more evident as children grow toward adolescence. ObjectiveWe aim to characterize the HIV reservoirs and their variability as per the virological and immunological profiles of HIV-1 non-B vertically infected adolescents receiving ART in Cameroon during the Adolescents' Viral Reservoirs study to provide accurate and reliable data for HIV cure research. MethodsThis study will involve HIV-1 non-B vertically infected adolescents selected from an existing cohort in our institution. Blood samples will be collected for analyzing immunological/virological profiles, including CD4/CD8 count, plasma viral load, immune activation/inflammatory markers, genotyping, and quantification of HIV-1 viral reservoirs. We will equally recruit an age-matched group of HIV-negative adolescents as control for immunological profiling. ResultsThis study received funding in November 2021 and was approved by the national institutional review board in December 2021. Sample collection will start in November 2022, and the study will last for 18 months. The HIV-1 sequences generated will provide information on the circulating HIV-1 subtypes to guide the selection of the most appropriate ART for the participants. The levels of immune biomarkers will help determine the immune profile and help identify factors driving persistent immune activation/inflammation in HIV-infected adolescents compared to those in HIV-uninfected adolescents. Analysis of the virological and immunological parameters in addition to the HIV-1 reservoir size will shed light on the characteristics of the viral reservoir in adolescents with HIV-1 non-B infection. ConclusionsOur findings will help in advancing the knowledge on HIV reservoirs, in terms of size and genetic variability in adolescents living with HIV. Such evidence will also help in understanding the effects of ART timing and duration on the size of the reservoirs among adolescents living with HIV—a unique population from whom the findings generated will largely contribute to designing functional cure strategies. International Registered Report Identifier (IRRID)PRR1-10.2196/41473

Abstract Multiple factors, such as immune disruption, prophylactic co-trimoxazole, and antiretroviral therapy, may influence the structure and function of the gut microbiome of children infected with HIV from birth. In order to understand whether HIV infection altered gut microbiome and to relate changes in microbiome structure and function to immune status, virological response and pediatric ART regimens, we characterized the gut microbiome of 87 HIV-infected and 82 non-exposed HIV-negative children from Yaounde, a cosmopolitan city in Cameroon. We found that children living with HIV had significantly lower alpha diversity in their gut microbiome and altered beta diversity that may not be related to CD4+ T cell count or viral load. There was an increased level of Akkermansia and Faecalibacterium genera and decreased level of Escherichia and other Gamma proteobacteria in children infected with HIV, among other differences. We noted an effect of ethnicity/geography on observed gut microbiome composition and that children on ritonavir-boosted protease inhibitor (PI/r)-based ART had gut microbiome composition that diverged more from HIV-negative controls compared to those on non-nucleoside reverse-transcriptase inhibitors-based ART. Further studies investigating the role of this altered gut microbiome in increased disease susceptibility are warranted for individuals who acquired HIV via mother-to-child transmission.