Hepatocellular carcinoma surveillance among people living with hepatitis B in Senegal (SEN-B): insights from a prospective cohort study.

BACKGROUND: Chronic hepatitis B virus (HBV) infection is the predominant cause of hepatocellular carcinoma in west Africa, yet data on the incidence of HBV-related hepatocellular carcinoma remain scarce. We aimed to describe the uptake and early outcomes of systematic ultrasound-based hepatocellular carcinoma screening in SEN-B, which is a prospective HBV cohort in Senegal. METHODS: In this prospective cohort study, we included treatment-naive, HBsAg-positive individuals who were referred to the two infectious diseases clinics (the Department of Tropical and Infectious Diseases and Ambulatory Treatment Center) at Fann University Hospital of Dakar, Senegal, between Oct 1, 2019, and Oct 31, 2022. All participants resided within the Dakar region. Participants underwent abdominal ultrasound, transient elastography, and clinical and virological assessments at inclusion and every 6 months. Liver lesions at least 1 cm in diameter on ultrasound were assessed using four-phase CT, MRI, or liver biopsy. Adherence to hepatocellular carcinoma surveillance was measured using the proportion of time covered, calculated by dividing the cumulative months covered by abdominal ultrasound examinations by the overall follow-up time, defined as the number of months from the date of cohort entry until the last recorded visit, hepatocellular carcinoma diagnosis, or death. Optimal adherence was defined as a proportion of time covered of 100%. FINDINGS: Overall, 755 (99·6%) of 758 participants had at least one abdominal ultrasound performed. The median age of the enrolled participants was 31 years (IQR 25-39), 355 (47·0%) of 755 participants were women, and 82 (10·9%) had a family history of hepatocellular carcinoma. 15 (2·0%) of 755 individuals were HBeAg positive, 206 (27·3%) of 755 individuals had HBV DNA of more than 2000 IU/mL, and 27 (3·6%) of 755 had elastography-defined liver cirrhosis. Of ten (1·3%) participants with a focal lesion at least 1 cm at initial assessment, CT or MRI ruled out hepatocellular carcinoma in nine, whereas imaging and subsequent liver biopsy confirmed one patient with hepatocellular carcinoma. Two further patients with hepatocellular carcinoma were diagnosed at study presentation due to the presence of portal thrombosis on ultrasound. Excluding the three participants with hepatocellular carcinoma identified at baseline, 752 participants were eligible for screening every 6 months. Median follow-up time was 12 months (IQR 6-18) and the median number of ultrasounds per patient was 3 (2-4). During 809·5 person-years of follow-up, one incident hepatocellular carcinoma was reported, resulting in an incidence rate of 1·24 cases per 1000 person-years (95% CI 0·18-8·80). Overall, 702 (93·0%) of 755 participants showed optimal hepatocellular carcinoma surveillance, but this proportion decreased to 77·8% (42 of 54 participants) after 24 months. INTERPRETATION: Hepatocellular carcinoma screening is feasible in HBV research cohorts in west Africa, but its longer-term acceptability needs to be evaluated. Long-term hepatocellular carcinoma incidence data are crucial for shaping tailored screening recommendations. FUNDING: Swiss National Science Foundation, the Swiss Cancer Research Foundation, the National Cancer Institute, and Roche Diagnostics. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Development and evaluation of a simple treatment eligibility score (HEPSANET) to decentralise hepatitis B care in Africa: a cross-sectional study.

BACKGROUND: Hepatitis B virus (HBV) elimination requires expanding and decentralising HBV care services. However, peripheral health facilities lack access to diagnostic tools to assess eligibility for antiviral therapy. Through the Hepatitis B in Africa Collaborative Network (HEPSANET), we aimed to develop and evaluate a score using tests generally available at lower-level facilities, to simplify the evaluation of antiviral therapy eligibility in people living with HBV. METHODS: We surveyed the availability of clinical and laboratory parameters across different health-care levels in sub-Saharan Africa. We used data from the HEPSANET dataset, the largest cross-sectional dataset of treatment-naive people living with HBV in sub-Saharan Africa, to derive and validate the score. Participants from this dataset were included in the analysis if they were aged 18 years or older and had liver fibrosis stages determined by a liver stiffness measurement or liver histopathology. Participants with co-infections or metabolic disorders were excluded. We allocated participants to the derivation and validation sets by geographical site. In the derivation set, we used stepwise logistic regression to identify the best performing parameters for identifying participants that met the 2017 European Association for the Study of the Liver (EASL) criteria. Regression coefficients were converted into integer points to construct simplified algorithms for different health-care levels. In the validation set, we estimated the area under the receiver operating characteristic, sensitivity, and specificity of the simplified algorithm for identifying antiviral therapy eligibility defined by the 2017 EASL criteria. FINDINGS: At 11 sites from eight countries that returned surveys, aspartate aminotransferase (AST), alanine aminotransferase (ALT), and platelet count were generally available at district hospital levels, and hepatitis B e antigen and point-of-care HBV DNA tests were available only at regional and provincial hospital levels or above. Among 2895 participants included from the HEPSANET database (1740 [60·1%] male, 1155 [39·9%] female), 409 (14·1%) met EASL antiviral therapy eligibility criteria. In the derivation set, the optimal district-level hospital score was: ALT (IU/L), less than 40 (0 points), 40-79 (+1), 80 or greater (+2); AST (IU/L), less than 40 (0), 40-79 (+1), 80 or greater (+2); and platelet counts (109/L), less than 100 (+2), 100-149 (+1), 150 or greater (0). When combined with family history and clinical data for decompensated cirrhosis that do not require any biological tests, a cut-off of 2 points or more had a sensitivity and specificity of 82% (95% CI 76-86) and 95% (93-96) to identify treatment-eligible individuals in the derivation set, and 78% (71-85) and 87% (86-89) in the validation set, respectively. INTERPRETATION: Using a score incorporating platelet counts, AST, and ALT, the majority of people living with HBV requiring antiviral therapy can be identified. Our findings suggest that clinical staging can be decentralised down to district hospital level in sub-Saharan Africa. FUNDING: European Association for the Study of the Liver Foundation, John C Martin Foundation. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Diagnosis, Management, and Outcome of Bart's Syndrome Observed in a Sub-Saharan African Country (Senegal, Dakar): 2 Case Reports.

Introduction: Bart's syndrome is an uncommon inherited congenital disorder associating congenital cutaneous aplasia of the extremities and inherited epidermolysis bullosa. Bilateral and symmetrical involvement of the limbs is exceptionally described on black skin. In most cases, the diagnosis is clinical; however, the management remains very difficult and the extended forms are a real therapeutic challenge. We report 2 cases of Bart's syndrome observed in a sub-Saharan African country (Senegal, Dakar). Case Presentation: It was about 2 premature female and male newborns. On physical examination, the girl presented with a total absence of skin on the limbs, associated with cutaneous detachment of the trunk representing a detached and detachable skin surface of 46%; the boy underwent a total absence of skin of more than 50% of the skin surface. The diagnosis of Bart's syndrome was set based on the typical clinical aspect. The blood count and CRP were normal for the girl whereas it revealed some disorders for the boy. The 2 newborns were urgently admitted to an incubator, and the intensive care was started with hyperhydration, anti-staphylococcal prophylaxis, and daily dermatological care with antiseptic baths and fatty dressings. Conclusion: Bart's syndrome is an uncommon genodermatosis characterized by a clinical triad associating congenital cutaneous aplasia of the extremities, inherited epidermolysis bullosa suspected in the presence of bubbles, and areas of cutaneous fragility and nail deformity. All types of which can be associated with this syndrome. The easy clinical diagnosis but the difficult management encumber the vital prognosis of our cases.

Malaria surveillance reveals parasite relatedness, signatures of selection, and correlates of transmission across Senegal.

We here analyze data from the first year of an ongoing nationwide program of genetic surveillance of Plasmodium falciparum parasites in Senegal. The analysis is based on 1097 samples collected at health facilities during passive malaria case detection in 2019; it provides a baseline for analyzing parasite genetic metrics as they vary over time and geographic space. The study's goal was to identify genetic metrics that were informative about transmission intensity and other aspects of transmission dynamics, focusing on measures of genetic relatedness between parasites. We found the best genetic proxy for local malaria incidence to be the proportion of polygenomic infections (those with multiple genetically distinct parasites), although this relationship broke down at low incidence. The proportion of related parasites was less correlated with incidence while local genetic diversity was uninformative. The type of relatedness could discriminate local transmission patterns: two nearby areas had similarly high fractions of relatives, but one was dominated by clones and the other by outcrossed relatives. Throughout Senegal, 58% of related parasites belonged to a single network of relatives, within which parasites were enriched for shared haplotypes at known and suspected drug resistance loci and at one novel locus, reflective of ongoing selection pressure.

Using MALDI-TOF MS to Identify Mosquitoes from Senegal and the Origin of Their Blood Meals.

Mosquitoes are arthropods that represent a real public health problem in Africa. Morphology and molecular biology techniques are usually used to identify different mosquito species. In recent years, an innovative tool, matrix-assisted desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), has been used to identify many arthropods quickly and at low cost, where equipment is available. We evaluated the ability of MALDI-TOF MS to identify mosquitoes collected in Senegal and stored for several months in silica gel, and to determine the origin of their blood meal. A total of 582 mosquitoes were collected and analysed. We obtained 329/582 (56.52%) MALDI-TOF MS good-quality spectra from mosquito legs and 123/157 (78.34%) good-quality spectra from engorged abdomens. We updated our home-made MALDI-TOF MS arthropod spectra database by adding 23 spectra of five mosquito species from Senegal that had been identified morphologically and molecularly. These included legs from Anopheles gambiae, Anopheles arabiensis, Anopheles cf. rivulorum, Culex nebulosus, Anopheles funestus, and three spectra from abdomens engorged with human blood. Having updated the database, all mosquitoes tested by MALDI-TOF MS were identified with scores greater than or equal to 1.7 as An. gambiae (n = 64), Anopheles coluzzii (n = 12), An. arabiensis (n = 1), An. funestus (n = 7), An. cf rivulorum (n = 1), Lutzia tigripes (n = 3), Cx. nebulosus (n = 211), Culex quinquefasciatus (n = 2), Culex duttoni (n = 1), Culex perfescus (n = 1), Culex tritaeniorhynchus (n = 1), and Aedes aegypti (n = 2). Blood meal identification by MALDI-TOF MS revealed that mosquitoes had fed on the blood of humans (n = 97), cows (n = 6), dogs (n = 2), goats (n = 1), sheep (n = 1), and bats (n = 1). Mixed meals were also detected. These results confirm that MALDI-TOF MS is a promising technique for identifying mosquitoes and the origin of their blood meal.

Informing a target product profile for rapid tests to identify HBV-infected pregnant women with high viral loads: a discrete choice experiment with African healthcare workers.

BACKGROUND: Elimination of mother-to-child transmission of hepatitis B virus (HBV) requires infant immunoprophylaxis and antiviral prophylaxis for pregnant women with high viral loads. Since real-time polymerase chain reaction (RT-PCR), a gold standard for assessing antiviral eligibility, is neither accessible nor affordable for women living in low-income and middle-income countries (LMICs), rapid diagnostic tests (RDTs) detecting alternative HBV markers may be needed. To inform future development of the target product profile (TPP) for RDTs to identify highly viremic women, we used a discrete choice experiment (DCE) and elicited preference and trade-off of healthcare workers (HCW) in Africa between the following four attributes of fictional RDTs: price, time-to-result, diagnostic sensitivity, and specificity. METHODS: Through an online questionnaire survey, we asked participants to indicate their preferred test from a set of two RDTs in seven choice tasks with varying levels of the four attributes. We used mixed multinomial logit models to quantify the utility gain or loss generated by each attribute. We attempted to define minimal and optimal criteria for test attributes that can satisfy ≥ 70% and ≥ 90% of HCWs, respectively, as an alternative to RT-PCR. RESULTS: A total of 555 HCWs from 41 African countries participated. Increases in sensitivity and specificity generated significant utility and increases in cost and time-to-result generated significant disutility. The size of the coefficients for the highest attribute levels relative to the reference levels were in the following order: sensitivity (ß = 3.749), cost (ß = -2.550), specificity (ß = 1.134), and time-to-result (ß = -0.284). Doctors cared most about test sensitivity, while public health practitioners cared about cost and midwives about time-to-result. For an RDT with 95% specificity, costing 1 US$, and yielding results in 20 min, the minimally acceptable test sensitivity would be 82.5% and the optimally acceptable sensitivity would be 87.5%. CONCLUSIONS: African HCWs would prefer an RDT with the following order of priority: higher sensitivity, lower cost, higher specificity, and shorter time-to-result. The development and optimization of RDTs that can meet the criteria are urgently needed to scale up the prevention of HBV mother-to-child transmission in LMICs.

Two decades of molecular surveillance in Senegal reveal changes in known drug resistance mutations associated with historical drug use and seasonal malaria chemoprevention.

Drug resistance in Plasmodium falciparum is a major threat to malaria control efforts. We analyzed data from two decades (2000-2020) of continuous molecular surveillance of P. falciparum parasite strains in Senegal to determine how historical changes in drug administration policy may have affected parasite evolution. We profiled several known drug resistance markers and their surrounding haplotypes using a combination of single nucleotide polymorphism (SNP) molecular surveillance and whole-genome sequence (WGS) based population genomics. We observed rapid changes in drug resistance markers associated with the withdrawal of chloroquine and introduction of sulfadoxine-pyrimethamine in 2003. We also observed a rapid increase in Pfcrt K76T and decline in Pfdhps A437G starting in 2014, which we hypothesize may reflect changes in resistance or fitness caused by seasonal malaria chemoprevention (SMC). Parasite populations evolve rapidly in response to drug use, and SMC preventive efficacy should be closely monitored.

Malaria surveillance reveals parasite relatedness, signatures of selection, and correlates of transmission across Senegal.

Parasite genetic surveillance has the potential to play an important role in malaria control. We describe here an analysis of data from the first year of an ongoing, nationwide program of genetic surveillance of Plasmodium falciparum parasites in Senegal, intended to provide actionable information for malaria control efforts. Looking for a good proxy for local malaria incidence, we found that the best predictor was the proportion of polygenomic infections (those with multiple genetically distinct parasites), although that relationship broke down in very low incidence settings (r = 0.77 overall). The proportion of closely related parasites in a site was more weakly correlated ( r = -0.44) with incidence while the local genetic diversity was uninformative. Study of related parasites indicated their potential for discriminating local transmission patterns: two nearby study areas had similarly high fractions of relatives, but one area was dominated by clones and the other by outcrossed relatives. Throughout the country, 58% of related parasites proved to belong to a single network of relatives, within which parasites were enriched for shared haplotypes at known and suspected drug resistance loci as well as at one novel locus, reflective of ongoing selection pressure.

Hepatitis B in Africa Collaborative Network: cohort profile and analysis of baseline data.

Approximately 80 million people live with chronic hepatitis B virus (HBV) infection in the WHO Africa Region. The natural history of HBV infection in this population is poorly characterised, and may differ from patterns observed elsewhere due to differences in prevailing genotypes, environmental exposures, co-infections, and host genetics. Existing research is largely drawn from small, single-centre cohorts, with limited follow-up time. The Hepatitis B in Africa Collaborative Network (HEPSANET) was established in 2022 to harmonise the process of ongoing data collection, analysis, and dissemination from 13 collaborating HBV cohorts in eight African countries. Research priorities for the next 5 years were agreed upon through a modified Delphi survey prior to baseline data analysis being conducted. Baseline data on 4,173 participants with chronic HBV mono-infection were collected, of whom 38.3% were women and the median age was 34 years (interquartile range 28-42). In total, 81.3% of cases were identified through testing of asymptomatic individuals. HBeAg-positivity was seen in 9.6% of participants. Follow-up of HEPSANET participants will generate evidence to improve the diagnosis and management of HBV in this region.

Systematic review and individual-patient-data meta-analysis of non-invasive fibrosis markers for chronic hepatitis B in Africa.

In sub-Saharan Africa, simple biomarkers of liver fibrosis are needed to scale-up hepatitis B treatment. We conducted an individual participant data meta-analysis of 3,548 chronic hepatitis B patients living in eight sub-Saharan African countries to assess the World Health Organization-recommended aspartate aminotransferase-to-platelet ratio index and two other fibrosis biomarkers using a Bayesian bivariate model. Transient elastography was used as a reference test with liver stiffness measurement thresholds at 7.9 and 12.2kPa indicating significant fibrosis and cirrhosis, respectively. At the World Health Organization-recommended cirrhosis threshold (>2.0), aspartate aminotransferase-to-platelet ratio index had sensitivity (95% credible interval) of only 16.5% (12.5-20.5). We identified an optimised aspartate aminotransferase-to-platelet ratio index rule-in threshold (>0.65) for liver stiffness measurement >12.2kPa with sensitivity and specificity of 56.2% (50.5-62.2) and 90.0% (89.0-91.0), and an optimised rule-out threshold (<0.36) with sensitivity and specificity of 80.6% (76.1-85.1) and 64.3% (62.8-65.8). Here we show that the World Health Organization-recommended aspartate aminotransferase-to-platelet ratio index threshold is inappropriately high in sub-Saharan Africa; improved rule-in and rule-out thresholds can optimise treatment recommendations in this setting.

Isolated esophageal tuberculosis: A case report.

BACKGROUND: Tuberculosis is endemic in Senegal. While its extra-pulmonary localization is rare, esophageal tuberculosis, particularly the isolated form, is exceptional. We report here a case of isolated esophageal tuberculosis in an immunocompetent patient. CASE SUMMARY: A 58-year-old man underwent consultation for mechanical dysphagia that had developed over 3 mo with non-quantified weight loss, anorexia, and fever. Upper digestive endoscopy showed extensive ulcerated lesions, suggesting neoplasia. The diagnosis was confirmed by histopathology, which showed gigantocellular epithelioid granuloma surrounding a caseous necrosis. Thoracoabdominal computed tomography scan did not show another localization of the tuberculosis. The outcome was favorable with treatment. CONCLUSION: Esophageal tuberculosis should be considered when dysphagia is associated with atypical ulcerated lesions of the esophageal mucosa, in an endemic area.

Survival of eight LLIN brands 6, 12, 24 and 36 months after a mass distribution campaign in rural and urban settings in Senegal.

BACKGROUND: Long lasting insecticidal nets (LLIN) are one of the core components of global malaria prevention and control. The lifespan of LLIN varies widely depending on the population or environment, and randomized studies are required to compare LLIN inaccording to arbitrary thresholds households under different field conditions. This study investigated survival of different LLIN brands in Senegal. METHODS: Ten thousand six hundred eight LLINs were distributed in five regions, each stratified by rural and urban setting. As part of the longitudinal follow-up, 2222 nets were randomly sampled and monitored from 6 to 36 months. Using random effects for households, Bayesian models were used to estimate independent survival by net type (Interceptor®, Life Net®, MAGNet™, Netprotect®, Olyset® Net, PermaNet® 2.0 R, PermaNet® 2.0 C, Yorkool® LN) and by area (rural/urban). In addition to survival, median survival time and attrition of each LLIN brand was determined. Attrition was defined as nets that were missing because they were reported given away, destroyed and thrown away, or repurposed. RESULTS: Three net types had a proportion of survival above 80% after 24 months: Interceptor®87.8% (95% CI 80-93.4); conical PermaNet® 2.0 86.9% (95% CI 79.3-92.4) and Life Net® 85.6% (95% CI 75-93). At 36 months, conical PermaNet® 2.0 maintained a good survival rate, 79.5% (95% CI 65.9-88.8). The attrition due to redistributed nets showed that the two conical net types (PermaNet® 2.0 and Interceptor®) were more often retained by households and their median retention time was well above 3 years (median survival time = 3.5 years for PermaNet® 2.0 and median survival time = 4 years for Interceptor®). Despite this good retention, Interceptor® had weak physical integrity and its median survival due to wear and tear was below 3 years (median survival time = 2.4 years). The odds ratio of survival was 2.5 times higher in rural settings than in urban settings (OR 2.5; 95% CI 1.7-3.7). CONCLUSIONS: Differences in survival among LLIN may be driven by brand, shape or environmental setting. In this study in Senegal, conical PermaNet® 2.0 were retained in households while rectangular PermaNet® 2.0 had lower retention, suggesting that net shape may play a role in retention and should be further investigated. Distribution of preferred LLIN shape, accompanied by good communication on care and repair, could lead to increased effective lifespan, and allow for longer intervals between universal coverage campaigns.

Malaria parasite carriage before and two years after the implementation of seasonal malaria chemoprevention: a case study of the Saraya health district, southern Senegal.

Background : Seasonal malaria chemoprevention (SMC) has been adopted and implemented in the southern regions of Senegal in children aged between three and 120 months since 2013. Scaling up this strategy requires its evaluation to assess the impact. This study was carried out to determine the dynamics of Plasmodium falciparum carriage before and after two years of SMC implementation. Methods : Four household surveys were conducted in villages in the health district of Saraya, which is a SMC implementation area in Senegal. These villages were selected using probability proportional to size sampling. Each selected village was divided into segments containing at least 50 children. In each segment, a household questionnaire was administered to the parents or legal representatives of children aged three to 120 months. Blood smears were collected to determine P. falciparum prevalence by microscopy one month before the first round of SMC, one month after the last round of the first SMC campaign and two years after the start of the implementation. Results : A total of 2008 children were included with a mean average age of 4.81 (+/-2.73) years. Of the study population, 50.33% were more than five years old and 50.3% were male. In 2013, mosquito net ownership was 99.4 % before the SMC campaign and 97.4% after. In 2015, it was 36.6% before and 45.8% after the campaign. In 2013, the prevalence of plasmodium carriage was 11.8% before and 6.1% after the SMC campaign. In 2015, the prevalence was 4.9% before the administration of SMC and this increased up to 15.3% after. Malaria prevalence was high among children over five years old and in boys. Conclusions : The decrease in Plasmodium falciparum parasite prevalence, which subsequently increased after two years of SMC implementation in this study, suggests adding an extra cycle of the SMC or adjusting the administration period.

Effect of mobile application user interface improvements on minimum expected home visit coverage by community health workers in Mali: a randomised controlled trial.

BACKGROUND: Proactive community case management (ProCCM) has shown promise to advance goals of universal health coverage (UHC). ProCCM community health workers (CHWs) face operational challenges when pursuing their goal of visiting every household in their service area at least twice monthly to proactively find sick patients. We developed a software extension (UHC Mode) to an existing CHW mobile application featuring user interface design improvements to support CHWs in planning daily home visits. We evaluated the effect of UHC Mode on minimum expected home visit coverage. METHODS: We conducted a parallel-group, two-arm randomised controlled trial of ProCCM CHWs in two separate regions in Mali. CHWs were randomly assigned to UHC Mode or the standard mobile application (control) with a 1:1 allocation. Randomisation was stratified by health catchment area. CHWs and other programme personnel were not masked to arm allocation. CHWs used their assigned intervention for 4 months. Using a difference-in-differences analysis, we estimated the mean change in minimum expected home visit coverage from preintervention to postintervention between arms. RESULTS: Enrolment occurred in January 2019. Of 199 eligible CHWs randomised to the intervention or control arm, 196 were enrolled and 195 were included in the analysis. Households whose CHW used UHC Mode had 2.41 times higher odds of minimum expected home visit coverage compared with households whose CHW used the control (95% CI 1.68 to 3.47; p<0.0005). Minimum expected home visit coverage in the UHC Mode arm increased 13.6 percentage points (95% CI 8.1 to 19.0) compared with the control arm. CONCLUSION: Our findings suggest UHC Mode is an effective tool that can improve home visit coverage and promote progress towards UHC when implemented in the ProCCM context. User interface design of health information systems that supports health workers' daily practices and meets their requirements can have a positive impact on health worker performance and home visit coverage. TRIAL REGISTRATION NUMBER: NCT04106921.

Spatiotemporal Dynamic of the RTS,S/AS01 Malaria Vaccine Target Antigens in Senegal.

The RTS,S/AS01 malaria vaccine confers only moderate protection against malaria. Evidence suggests that the effectiveness of the RTS,S/AS01 vaccine depends upon the parasite population genetics, specifically regarding the circumsporozoite protein haplotypes in the population. We investigated Plasmodium falciparum circumsporozoite protein (PfCSP) gene sequences from two endemic sites in 2018 in Senegal. The PfCSP sequences were compared with those retrieved from the Pf3k genome database. In the central repeat region of PfCSP, the distribution of haplotypes differed significantly between the two study sites (Fisher's exact test, P < 0.001). No 3D7 vaccine strain haplotype was observed in this locus. In the C-terminal region, there was no significant difference in haplotypes distribution between Kedougou and Diourbel (Fischer's exact test, P = 0.122). The 3D7 haplotype frequency was 8.4% in early samples (2001-2011), but then it contracted in the subsequent years. The extensive plasticity of the P. falciparum genes coding the RTS,S/AS01 vaccine target antigens may influence the immune responses to circulating alleles. Monitoring the genetic diversity baseline and its dynamics over time and space would be instrumental in rationally improving the malaria RTS,S/AS01 vaccine and/or its implementation schedule.

An Integrated Bile Acids Profile Determination by UHPLC-MS/MS to Identify the Effect of Bile Acids Supplement in High Plant Protein Diet on Common Carp (Cyprinus carpio).

Bile acids (BAs) have considerable importance in the metabolism of glycolipid and cholesterol. The purpose of the present study is to clarify the effects of bile acids supplementary in a high plant protein diet for the common carp BA profiles and hepatopancreas and intestine health. An 11-week feeding trial was conducted with high plant protein diet (18% soybean meal and 18% cottonseed protein concentrated) (HP) and HP added 600 mg/kg BAs (HP+BAs) for common carp, and then, the UHPLC-MS/MS technology was used to analyze the BAs in the bile and plasma of two groups. HP could induce vacuolation of hepatocytes and accumulation of glycogen in the common carp, while these phenotypes were significantly improved in the HP+BAs group. In addition, the BA profile of the HP group and HP+BAs group are described in detail, for the common carp bile with treatment by exogenous BAs, TCA, CA, TßMCA, and TωMCA were the main components. Furthermore, in the HP+BAs group plasma, CDCA, CA, LCA, and GCDCA increased significantly; they could activate TGR5, and the activation of hepatopancreas TGR5 might regulate glucose metabolism to relieve hepatopancreas glycogen accumulation. This study proved that BAs supplemented to plant protein diet could relieve the common carp hepatopancreas glycogen accumulation by changing the BAs' profile, thereby promoting its healthy growth, which has important guiding significance for the promotion of aquaculture development and makes an important contribution to expanding the strategic space of food security.

Genetic surveillance for monitoring the impact of drug use on Plasmodium falciparum populations.

The use of antimalarial drugs is an effective strategy in the fight against malaria. However, selection of drug resistant parasites is a constant threat to the continued use of this approach. Antimalarial drugs are used not only to treat infections but also as part of population-level strategies to reduce malaria transmission toward elimination. While there is strong evidence that the ongoing use of antimalarial drugs increases the risk of the emergence and spread of drug-resistant parasites, it is less clear how population-level use of drug-based interventions like seasonal malaria chemoprevention (SMC) or mass drug administration (MDA) may contribute to drug resistance or loss of drug efficacy. Critical to sustained use of drug-based strategies for reducing the burden of malaria is the surveillance of population-level signals related to transmission reduction and resistance selection. Here we focus on Plasmodium falciparum and discuss the genetic signatures of a parasite population that are correlated with changes in transmission and related to drug pressure and resistance as a result of drug use. We review the evidence for MDA and SMC contributing to malaria burden reduction and drug resistance selection and examine the use and impact of these interventions in Senegal. Throughout we consider best strategies for ongoing surveillance of both population and resistance signals in the context of different parasite population parameters. Finally, we propose a roadmap for ongoing surveillance during population-level drug-based interventions to reduce the global malaria burden.

Hepatocellular carcinoma in Senegal: epidemiological, clinical and etiological aspects about 229 cases at Hôpital Principal de Dakar.

Hepatocellular carcinoma (HCC) is a major public health problem in Senegal, and the third most common cancer in terms of incidence. However, there are no recent data on the characteristics of this pathology in our country. The aim was to describe the epidemiological, clinical, aetiological and therapeutic aspects of HCC at Hôpital Principal de Dakar, Senegal. We did a descriptive retrospective study, including patients hospitalized from January 2012 to December 2017. We included 229 patients. The mean age was 47.4 years (21 - 88 years), and 77 patients (33.6%) were under 40 years of age. The sex ratio was 6.6. Twelve patients (5.2%) had a family history of 1st degree cirrhosis or HCC. Ten patients (4.4%) were previously treated with nucleotide analogues. The most common clinical sign at diagnosis was abdominal pain (91.7%). Alpha-fetoprotein level was normal in 12.2% of patients, and greater than 400 ng/ml in 68.1% of cases. Abdominal ultrasound found nodular HCC in 122 patients (68.2%), infiltrative HCC in 19 patients (10.6%), and was normal in 38 cases (21.2%). Subjacent cirrhosis was detected in 71.3% of cases. Abdominal computed tomography (CT) scan showed compatible HCC lesions in 88.8% of cases. A histological diagnosis was obtained in 2 patients (0.9%). The most common etiological factor was hepatitis B virus (69.4%), characterized mostly by a younger age (p = 0.001). In 20.9% of cases, no aetiology was found. An advanced or terminal stage (BCLC C/D) was found in 217 cases (94.8%). The treatment was curative in 12 patients (5.2%), and palliative in 7 cases (3.1%). The evolution at one year was favourable in 6 patients (2.6%). Hepatocellular carcinoma (HCC) is a disease that mainly affects young male adults in Senegal. The main aetiological factor remains HBV infection. The diagnosis is made at an advanced stage and the prognosis very bad.

Performance of MALDI-TOF Mass Spectrometry to Determine the Sex of Mosquitoes and Identify Specific Colonies from French Polynesia.

Mosquitoes are the main arthropod vectors of human pathogens. The current methods for mosquito identification include morphological and molecular methods. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS), now routinely used for bacterial identification, has recently emerged in the field of entomology. The aim of this study was to use MALDI-TOF MS to identify mosquito colonies from French Polynesia. Five hundred specimens from French Polynesia belonging to three species, Aedes aegypti, Aedes polynesiensis, and Culex quinquefasciatus, were included in the study. Testing the legs of these mosquitoes by MALDI-TOF MS revealed a 100% correct identification of all specimens at the species level. The MALDI-TOF MS profiles obtained allowed differentiation of male from female mosquitoes and the specific identification of female mosquito colonies of the same species but different geographic origin.

Genomic investigation of atypical malaria cases in Kanel, northern Senegal.

BACKGROUND: The diagnosis of malaria cases in regions where the malaria burden has decreased significantly and prevalence is very low is more challenging, in part because of reduced clinical presumption of malaria. The appearance of a cluster of malaria cases with atypical symptoms in Mbounguiel, a village in northern Senegal where malaria transmission is low, in September 2018 exemplifies this scenario. The collaboration between the National Malaria Control Programme (NMCP) at the Senegal Ministry of Health and the Laboratory of Parasitology and Mycology at Cheikh Anta Diop University worked together to evaluate this cluster of malaria cases using molecular and serological tools. METHODS: Malaria cases were diagnosed primarily by rapid diagnostic test (RDT), and confirmed by photo-induced electron transfer-polymerase chain reaction (PET-PCR). 24 single nucleotide polymorphisms (SNPs) barcoding was used for Plasmodium falciparum genotyping. Unbiased metagenomic sequencing and Luminex-based multi-pathogen antibody and antigen profiling were used to assess exposure to other pathogens. RESULTS: Nine patients, of 15 suspected cases, were evaluated, and all nine samples were found to be positive for P. falciparum only. The 24 SNPs molecular barcode showed the predominance of polygenomic infections, with identifiable strains being different from one another. All patients tested positive for the P. falciparum antigens. No other pathogenic infection was detected by either the serological panel or metagenomic sequencing. CONCLUSIONS: This work, undertaken locally within Senegal as a collaboration between the NMCP and a research laboratory at University of Cheikh Anta Diop (UCAD) revealed that a cluster of malaria cases were caused by different strains of P. falciparum. The public health response in real time demonstrates the value of local molecular and genomics capacity in affected countries for disease control and elimination.