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  Hétérogénéité de la transmission du paludisme urbain dans les districts sanitaires de Bouaké, Côte d’Ivoire

  Konan Fabrice ASSOUHO, Négnorogo GUINDO-COULIBALY, Dounin Danielle ZOH, Konan Rodolphe Mardoché AZONGNIBO, Akré Maurice ADJA

  RÉSUMÉJustificationDes travaux réalisés dans la ville de Bouaké il y a environ 20 ans ont montré un fort niveau de transmission du paludisme essentiellement dû au vecteur Anopheles gambiae, avec une recrudescence manifestée en saison pluvieuse. Des efforts de lutte à travers la distribution de moustiquaires imprégnées d’insecticides à longue durée d’action (MILDA) ont été menés par le Programme national de lutte contre le paludisme. Cependant, la crise politico-militaire de 2002 à 2011 a provoqué un important flux migratoire des habitants de cette ville, laissant le milieu naturel préservé. Le retour des populations à Bouaké a donc nécessité la mise en place de nouveaux programmes de lutte avec l’utilisation des MILDA. De nouvelles études de recherche sont maintenant nécessaires afin de recueillir des données sur les paramètres de transmission du paludisme. La présente étude s’inscrit dans ce contexte. Elle a pour objectif d’évaluer la transmission vectorielle du paludisme à travers la détermination de paramètres entomologiques dans les trois districts sanitaires de la ville de Bouaké.Matériel et méthodesLes investigations ont été menées en milieu urbain pendant la saison pluvieuse, du 10 au 29 juin 2016, dans les trois districts sanitaires de Bouaké (Nord-Ouest, Nord-Est, Sud). Les moustiques ont été collectés par captures sur sujet humain et identifiés. Le comportement trophique des femelles vectrices a été examiné et les paramètres entomologiques de la transmission du paludisme ont été estimés. L’âge physiologique des femelles vectrices a été déterminé après la dissection de leurs ovaires et les moustiques infestés par Plasmodium falciparum ont été détectés par le test ELISA-CSP.RésultatsAn. gambiae a été la seule espèce vectrice du paludisme collectée. Elle a présenté une tendance à l’endophagie et un taux moyen de parturité supérieur à 90 % dans tous les districts. Les densités agressives de l’espèce étaient respectivement de 3,6, 15,5 et 14,4 piqûres/homme/nui

  Parasitologie et mycologieMaladies infectieuses et tropicalesLicence : https://creativecommons.org/licenses/by/4.0/ Cet article en libre accès est distribué selon les termes de la licence Creative Commons CC BY 4.0 ().

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  Heterogeneity of use, access, and retention of insecticide-treated nets: Implications for subnational tailoring to maximise malaria control

  Background:While insecticide-treated nets (ITNs) are highly impactful and cost-effective for malaria control, they are primarily distributed through three-yearly mass campaigns yet are typically retained for shorter periods. It is unclear whether disease control could be best improved with more efficacious ITNs and/or increased distribution frequency. There are increased calls to optimise resources through subnational tailoring of interventions, though benefits will depend on how long people use ITNs and how this varies between regions; yet this has not been previously quantified subnationally.Methods:We estimated subnational differences in ITN use, access, and retention for six countries (Burkina Faso, Ghana, Malawi, Mali, Mozambique, and Senegal) and used these to calibrate a Plasmodium falciparum transmission dynamics model, generating subnational case estimates under different distribution strategies.Results:On average, people used their ITNs for 21 months though this varied subnationally from 12 to 38 months. Shifting from triennial to biennial campaigns is projected to increase mean use across all regions from 45.4% to 53.9% and avert substantial additional cases in moderate and high transmission settings. Projected case increases following campaign deprioritisation or switching to less efficacious ITN classes are strongly associated with transmission intensity.Conclusions:Although transmission intensity remains important for subnational tailoring, other factors, such as ITN use given access, meaningfully influence optimal deployment strategies. The framework highlights how routinely collected data can aid policymakers in tailoring disease control programmes at subnational levels.Funding:The work was funded by the Global Fund under the Net Transition Initiative. ACG and TSC acknowledge funding from the MRC Centre for Global Infectious Disease Analysis (MR/R015600/1), jointly funded by the MRC and the UK Foreign, Commonwealth and Development Office (FCDO) under

  Parasitologie et mycologieMaladies infectieuses et tropicalesSanté publiqueLicence : Creative Commons Attribution License This article is distributed under the terms of the, which permits unrestricted use and redistribution provided that the original author and source are credited.

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  Heterogeneous alleles comprising G6PD deficiency trait in West Africa exert contrasting effects on two major clinical presentations of severe malaria

  Shivang S. Shah, Kirk A. Rockett, Muminatou Jallow, Fatou Sisay-Joof, Kalifa A. Bojang, Margaret Pinder, Anna Jeffreys, Rachel Craik, Christina Hubbart, Thomas E. Wellems, Dominic P. Kwiatkowski

  BackgroundGlucose-6-phosphate dehydrogenase (G6PD) deficiency exhibits considerable allelic heterogeneity which manifests with variable biochemical and clinical penetrance. It has long been thought that G6PD deficiency confers partial protection against severe malaria, however prior genetic association studies have disagreed with regard to the strength and specificity of a protective effect, which might reflect differences in the host genetic background, environmental influences, or in the specific clinical phenotypes considered.MethodsA case-control association study of severe malaria was conducted in The Gambia, a region in West Africa where there is considerable allelic heterogeneity underlying expression of G6PD deficiency trait, evaluating the three major nonsynonymous polymorphisms known to be associated with enzyme deficiency (A968G, T542A, and C202T) in a cohort of 3836 controls and 2379 severe malaria cases.ResultsEach deficiency allele exhibited a similar trend toward protection against severe malaria overall (15–26 % reduced risk); however, in stratifying severe malaria to two of its constituent clinical subphenotypes, severe malarial anaemia (SMA) and cerebral malaria (CM), the three deficiency alleles exhibited trends of opposing effect, with risk conferred to SMA and protection with respect to CM. To assess the overall effect of G6PD deficiency trait, deficiency alleles found across all three loci were pooled. G6PD deficiency trait was found to be significantly associated with protection from severe malaria overall (OR 0.83 [0.75–0.92], \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$P = 0.0006$$\end{document}P=0.0006), but this was limited to CM (OR 0.73 [0.61–0.87], \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{a

  Biologie cellulaire et moléculaireGénétiqueBiostatistiques et épidémiologieLicence : Open Access http://creativecommons.org/licenses/by/4.0/ http://creativecommons.org/publicdomain/zero/1.0/ This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (), which permits unrestricted use, distribution, and reproduction in any medium, provid

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  Heterologous Protection against Malaria after Immunization with Plasmodium falciparum Sporozoites

  BackgroundSterile protection in >90% of volunteers against homologous Plasmodium falciparum infection has been achieved only using the controlled human malaria infection (CHMI) model. This efficient model involves whole parasite immunizations under chloroquine prophylaxis (CPS-immunization), requiring only 30–45 mosquitoes bites infected with P. falciparum-sporozoites. Given the large diversity of P. falciparum parasites, it is essential to assess protection against heterologous parasite strains.MethodsIn an open-label follow-up study, 16 volunteers previously CPS-immunized and challenged with P. falciparum NF54 (West-Africa) in a dose de-escalation and challenge trial were re-challenged with clone NF135.C10 (Cambodia) at 14 months after the last immunization (NCT01660854).ResultsTwo out of thirteen NF54 protected volunteers previously fully protected against NF54 were also fully protected against NF135.C10, while 11/13 showed a delayed patency (median prepatent period of 10.5 days (range 9.0–15.5) versus 8.5 days in 5 malaria-naïve controls (p = 0.0005). Analysis of patency by qPCR indicated a 91 to >99% estimated reduction of liver parasite load in 7/11 partially protected subjects. Three volunteers previously not protected against NF54, were also not protected against NF135.C10.ConclusionThis study shows that CPS-immunization can induce heterologous protection for a period of more than one year, which is a further impetus for clinical development of whole parasite vaccines.Trial RegistrationClinicaltrials.gov NCT01660854

  Biologie cellulaire et moléculaireGénétiqueParasitologie et mycologieLicence : This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.

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  Hidradenite suppurative et psoriasis: anguille sous roche

  Mouna Bouaddi, Badredine Hassam

  ImmunologieMaladies infectieuses et tropicalesLicence : The Pan African Medical Journal - ISSN 1937-8688. This is an Open Access article distributed under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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  Hidradénocarcinome du cuir chevelu : à propos d'un cas

  Ali Sbai, Asmae Ouabdelmoumene, Farid Naciri, Mohammed Elhfid, Loubna Mezouar

  L'hidradénocarcinome est une tumeur annexielle maligne extrêmement rare. Caractérisée par la fréquence des récidives locorégionales et des métastases à distance. Le diagnostic histopathologique de malignité se fait sur des critères architecturaux et cytologiques particuliers .la chirurgie d'exérèse large représente l'essentiel du traitement. Une radiothérapie adjuvante s'avère obligatoire en cas de facteurs de récidive locale. Le curage ou la radiothérapie prophylactiques des aires ganglionnaires régionales non envahies pourraient jouer un rôle primordial dans la réduction du risque de récidives locorégionales.

  Licence : The Pan African Medical Journal - ISSN 1937-8688. This is an Open Access article distributed under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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  Hidradénome papillifère

  Rajaa Elouarradi, Ouafa Hocar

  Licence : The Pan African Medical Journal - ISSN 1937-8688. This is an Open Access article distributed under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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  Hidrocystome palpébral

  Fatima-Zahra Agharbi

  Licence : The Pan African Medical Journal - ISSN 1937-8688. This is an Open Access article distributed under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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• Article libreArticleEn anglais

  High acceptability of newborn screening for sickle cell disease among post-natal mothers in Western Kenya

  Sickle cell disease is a genetically inherited blood disorder that manifests early in life with resultant significant health complications. Globally, nearly three quarters of all affected babies are in sub-Saharan Africa. Early identification of babies with sickle cell disease through newborn screening followed by early linkage to care is recommended. However, the program has not been widely adopted in the sub-Saharan Africa. The Kenyan ministry of health, in 2020, published a policy on newborn screening for sickle cell disease from levels 2–6 healthcare facilities. However, evidence on acceptability of newborn screening to scale up newborn screening program is scarce. Few studies have been conducted across the sub-Saharan Africa to assess the acceptability of newborn screening for sickle cell disease with conflicting results. This study assessed factors associated with acceptability of newborn screening among mothers of newborns delivered at Homa bay county teaching and referral hospital, western Kenya. This study employed a cross-sectional design among postnatal mothers at Homa bay county teaching and referral hospital with 399 postnatal mothers enrolled into the study. After obtaining informed consent from the postnatal mothers, a semi-structured questionnaire was used for data collection. Maternal sociodemographic characteristics, knowledge, and perception were assessed. Babies were also screened for sickle cell disease using Sickle SCAN point-of-care test. The acceptability was calculated as percentage of mothers accepting to have their babies screened. Data were analyzed using logistic regression to explore factors associated with acceptability of newborn screening for sickle cell disease. Ninety-four percent of mothers accepted newborn screening for sickle cell disease. Only maternal age and occupation were significantly associated with acceptability of newborn screening for sickle cell disease. Mothers aged 25−34 years were 3 times less likely to accept newb

  Biologie cellulaire et moléculaireGénétiqueHématologieLicence : Creative Commons Attribution License This is an open access article distributed under the terms of the, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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  High attack rate for malaria through irregular migration routes to a country on verge of elimination

  Kolitha Wickramage, Risintha G Premaratne, Sharika L Peiris, Davide Mosca

  Irregular migration in the form of human smuggling and human trafficking is recognized as a global public health issue. Thirty-two cases of Plasmodium falciparum were detected in 534 irregular migrants returning to Sri Lanka via failed human smuggling routes from West Africa in 2012, contributing to the largest burden of imported cases in Sri Lanka as it entered elimination phase. Beyond the criminality and human rights abuse, irregular migration plays an important, but often forgotten, pathway for malaria re-introduction. Active surveillance of the growing numbers of irregular migrant flows becomes an important strategy as Sri Lanka advances towards goals of malaria elimination.

  Parasitologie et mycologieMaladies infectieuses et tropicalesLicence : http://creativecommons.org/licenses/by/2.0 This is an Open Access article distributed under the terms of the Creative Commons Attribution License (), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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  High frequencies of F1534C and V1016I kdr mutations and association with pyrethroid resistance in Aedes aegypti from Somgandé (Ouagadougou), Burkina Faso

  Aboubacar Sombié, Erisha Saiki, Félix Yaméogo, Tatsuya Sakurai, Takahiro Shirozu, Shinya Fukumoto, Antoine Sanon, David Weetman, Philip J. McCall, Hirotaka Kanuka, Athanase Badolo

  BackgroundResistance to pyrethroid insecticides involving kdr mutations is widespread in Aedes aegypti (L.) (Diptera: Culicidae) and potentially could impact control efforts in endemic countries. Dengue cases had been sporadic in Burkina Faso for over a decade prior to the 2016–2017 outbreak that resulted in 15,074 suspected cases and 36 deaths, mainly in Ouagadougou. These outbreaks highlighted the lack of information on numerous aspects of the biology, behaviour and insecticide status of local dengue vector populations that are fundamental to vector control.ResultsWe investigated the insecticide resistance profiles and the kdr mutations involved in pyrethroid resistance of Ae. aegypti from Somgandé, a district of Ouagadougou. WHO bioassays revealed that the local Ae. aegypti populations were highly resistant to pyrethroids with mortalities of 15% for permethrin and 37% for deltamethrin. Resistance to carbamates was also detected with mortalities of 55% for propoxur and 90% for bendiocarb, but high mortalities (> 97%) to organophosphates (malathion and fenitrothion) indicated susceptibility. Allele-specific PCR and voltage-gated sodium channel gene sequencing showed a very high frequency (97%) of the F1534C kdr allele whilst the V1016I kdr mutation frequency was 46%. Association of dual-locus kdr mutations was detected for permethrin resistance.ConclusionWe conclude that in this locality of Burkina Faso, Ae. aegypti is resistant to pyrethroid and carbamate insecticides but remains susceptible to organophosphates, providing useful information for possible future control.

  Biologie cellulaire et moléculaireGénétiqueMicrobiologie (bactériologie, virologie)Licence : Open Access http://creativecommons.org/licenses/by/4.0/ http://creativecommons.org/publicdomain/zero/1.0/ This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (), which permits unrestricted use, distribution, and reproduction in any medium, provid

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  High Genetic Differentiation between the M and S Molecular Forms of Anopheles gambiae in Africa

  Background Anopheles gambiae, a major vector of malaria, is widely distributed throughout sub-Saharan Africa. In an attempt to eliminate infective mosquitoes, researchers are trying to develop transgenic strains that are refractory to the Plasmodium parasite. Before any release of transgenic mosquitoes can be envisaged, we need an accurate picture of the differentiation between the two molecular forms of An. gambiae, termed M and S, which are of uncertain taxonomic status.Methodology/Principal FindingsInsertion patterns of three transposable elements (TEs) were determined in populations from Benin, Burkina Faso, Cameroon, Ghana, Ivory Coast, Madagascar, Mali, Mozambique, Niger, and Tanzania, using Transposon Display, a TE-anchored strategy based on Amplified Fragment Length Polymorphism. The results reveal a clear differentiation between the M and S forms, whatever their geographical origin, suggesting an incipient speciation process.Conclusions/SignificanceAny attempt to control the transmission of malaria by An. gambiae using either conventional or novel technologies must take the M/S genetic differentiation into account. In addition, we localized three TE insertion sites that were present either in every individual or at a high frequency in the M molecular form. These sites were found to be located outside the chromosomal regions that are suspected of involvement in the speciation event between the two forms. This suggests that these chromosomal regions are either larger than previously thought, or there are additional differentiated genomic regions interspersed with undifferentiated regions.

  Biologie cellulaire et moléculaireGénétiqueParasitologie et mycologieLicence : This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are properly credited.

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  High malaria transmission sustained by Anopheles gambiae s.l. occurring both indoors and outdoors in the city of Yaoundé, Cameroon

  Patricia Doumbe-Belisse, Carmene Sandra Ngadjeu, Nadege Sonhafouo-Chiana, Abdou Talipouo, Landre Djamouko-Djonkam, Edmond Kopya, Roland Bamou, Jean Claude Toto, Souleyman Mounchili, Raymond Tabue, Parfait Awono-Ambene, Charles Sinclair Wondji, Flobert Njiokou, Christophe Antonio-Nkondjio

  Background: Malaria remains a major public health problem in Cameroon; however, despite reports on the adaptation of anopheline species to urban habitats, there is still not enough information on malaria transmission pattern in urban settings. In the frame of a larval control trial in the city of Yaoundé, we conducted baseline surveys to assess malaria transmission dynamics in this city. Methods: Adult mosquitoes were collected indoors and outdoors using CDC light traps and human landing catches from March 2017 to March 2018 in 30 districts of Yaoundé, Cameroon. Mosquitoes were sorted by genus and identified to the species level using PCR. The TaqMan method and ELISA were used to determine mosquito infection status to Plasmodium. Bioassays were conducted to assess female Anopheles gambiae susceptibility to insecticides. Results: A total of 218,991 mosquitoes were collected. The main malaria vectors were An. gambiae s.l. (n=6154) and An. funestus s.l. (n=229). Of the 1476 An. gambiae s.l. processed by PCR, 92.19% were An. coluzzii and 7.81% An. gambiae. An. funestus s.l. was composed of 93.01% (173/186) An. funestus and 4.84% (13/186) An. leesoni. The average biting rate of anopheline was significantly high outdoor than indoor (P=0.013). Seasonal variation in mosquito abundance and biting rate was recorded. The infection rate by Plasmodium falciparum was 2.13% (104/4893 mosquitoes processed). The annual entomological inoculation rate was found to vary from 0 to 92 infective bites/man/year (ib/m/y). Malaria transmission risk was high outdoor (66.65 ib/m/y) compared to indoor (31.14 ib/m/y). An. gambiae s.l. was found highly resistant to DDT, permethrin and deltamethrin. High prevalence of the West Africa kdr allele 1014F was recorded and this was not found to influence An. gambiae s.l. infection status. Conclusion: The study suggests high malaria transmission occurring in the city of Yaoundé and call for immediate actions to improve control strategies.

  Biologie cellulaire et moléculaireGénétiqueBiostatistiques et épidémiologieLicence : This is an open access article distributed under the terms of the Creative Commons Attribution Licence, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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  High Nasal Carriage Rate of Staphylococcus aureus Containing Panton-Valentine leukocidin- and EDIN-Encoding Genes in Community and Hospital Settings in Burkina Faso

  Abdoul-Salam Ouedraogo, Catherine Dunyach-Remy, Aimée Kissou, Soufiane Sanou, Armel Poda, Carole G. Kyelem, Jérôme Solassol, Anne-Laure Bañuls, Philippe Van De Perre, Rasmata Ouédraogo, Hélène Jean-Pierre, Jean-Philippe Lavigne, Sylvain Godreuil

  The objectives of the present study were to investigate the rate of S.aureus nasal carriage and molecular characteristics in hospital and community settings in Bobo Dioulasso, Burkina Faso. Nasal samples (n = 219) were collected from 116 healthy volunteers and 103 hospitalized patients in July and August 2014. Samples were first screened using CHROMagar Staph aureus chromogenic agar plates, and S. aureus strains were identified by mass spectrometry. Antibiotic susceptibility was tested using the disk diffusion method on Müller-Hinton agar. All S. aureus isolates were genotyped using DNA microarray. Overall, the rate of S. aureus nasal carriage was 32.9% (72/219) with 29% in healthy volunteers and 37% in hospital patients. Among the S. aureus isolates, only four methicillin-resistant S. aureus (MRSA) strains were identified and all in hospital patients (3.9%). The 72 S. aureus isolates from nasal samples belonged to 16 different clonal complexes, particularly to CC 152-MSSA (22 clones) and CC1-MSSA (nine clones). Two clones were significantly associated with community settings: CC1-MSSA and CC45-MSSA. The MRSA strains belonged to the ST88-MRSA-IV or the CC8-MRSA-V complex. A very high prevalence of toxinogenic strains 52.2% (36/69), containing Panton-Valentine leucocidin- and EDIN-encoding genes, was identified among the S. aureus isolates in community and hospital settings. This study provides the first characterization of S. aureus clones and their genetic characteristics in Burkina Faso. Altogether, it highlights the low prevalence of antimicrobial resistance, high diversity of methicillin-sensitive S. aureus clones and high frequency of toxinogenic S. aureus strains.

  Biologie cellulaire et moléculaireGénétiqueBiostatistiques et épidémiologieLicence : This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in

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  High prevalence of extended-spectrum ß-lactamase producing enterobacteriaceae among clinical isolates in Burkina Faso

  Abdoul-Salam Ouedraogo, Mahamadou Sanou, Aimée Kissou, Soufiane Sanou, Hermann Solaré, Firmin Kaboré, Armel Poda, Salim Aberkane, Nicolas Bouzinbi, Idrissa Sano, Boubacar Nacro, Lassana Sangaré, Christian Carrière, Dominique Decré, Rasmata Ouégraogo, Hélène Jean-Pierre, Sylvain Godreuil

  BackgroundNothing is known about the epidemiology and resistance mechanisms of extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) in Burkina Faso. The objective of this study was to determine ESBL-PE prevalence and to characterize ESBL genes in Burkina Faso.MethodsDuring 2 months (June-July 2014), 1602 clinical samples were sent for bacteriologic investigations to the microbiology laboratories of the tree main hospitals of Burkina Faso. Isolates were identified by mass spectrometry using a matrix-assisted laser desorption ionization-time of flight (MALDI-TOF) BioTyper. Antibiotic susceptibility was tested using the disk diffusion method on Müller-Hinton agar. The different ESBL genes in potential ESBL-producing isolates were detected by PCR and double stranded DNA sequencing. Escherichia coli phylogenetic groups were determined using a PCR-based method.ResultsESBL-PE frequency was 58 % (179 strains among the 308 Enterobacteriaceae isolates identified in the collected samples; 45 % in outpatients and 70 % in hospitalized patients). The CTX-M-1 group was dominant (94 %, CTX-M-15 enzyme), followed by the CTX-M-9 group (4 %). ESBL producers were more often found in E. coli (67.5 %) and Klebsiella pneumoniae (26 %) isolates. E. coli isolates (n = 202; 60 % of all Enterobacteriaceae samples) were distributed in eight phylogenetic groups (A = 49, B1 = 15, B2 = 43, C = 22, Clade I = 7, D = 37, F = 13 and 16 unknown); 22 strains belonged to the sequence type ST131. No association between a specific strain and ESBL production was detected.ConclusionsThis report shows the alarming spread of ESBL genes in Burkina Faso. Public health efforts should focus on education (population and healthcare professionals), surveillance and promotion of correct and restricted antibiotic use to limit their dissemination.

  Biologie cellulaire et moléculaireGénétiqueBiostatistiques et épidémiologieLicence : Open Access http://creativecommons.org/licenses/by/4.0/ http://creativecommons.org/publicdomain/zero/1.0/ This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (), which permits unrestricted use, distribution, and reproduction in any medium, provid

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  High prevalence of hepatitis B infections in Burkina Faso (1996–2017): a systematic review with meta-analysis of epidemiological studies

  Moussa Lingani, Tomoyuki Akita, Serge Ouoba, Armel Moumini Sanou, Aya Sugiyama, Zekiba Tarnagda, Masayuki Ohisa, Halidou Tinto, Shunji Mishiro, Junko Tanaka

  BackgroundHepatitis B virus (HBV) infection was long considered an important public health concern in Burkina Faso and still represents a major cause of liver cancer and cirrhosis in the active population. To counter the problem, a national strategic plan was developed and adopted in July 2017 to coordinate viral hepatitis elimination’s efforts. However evidence to support its implementation remains scanty and scattered. The main purpose of this study was to summarize available information from per-reviewed articles published over the last two decades to accurately estimate the prevalence of HBV infection in Burkina Faso.MethodsWe conducted a systematic search with meta-analysis of scientific articles using Science-Direct, Web-of-Science, PubMed/Medline, and Google Scholar. We systematically assessed all relevant publications that measured the prevalence of hepatitis B surface antigen and which were published between 1996 and 2017. We estimated the national HBV prevalence and its 95% confident interval. We subsequently adjusted the meta-analysis to possible sources of heterogeneity.ResultsWe retrieved and analyzed a total of 22 full text papers including 99,672 participants. The overall prevalence was 11.21%. The prevalence after adjustment were 9.41%, 11.11%, 11.73% and 12.61% in the general population, pregnant women, blood donors and HIV-positive persons respectively. The prevalence was higher before implementation of HBV universal vaccination and decreased from 12.80% between 1996 and 2001 to 11.11% between 2012 and 2017. The prevalence was also higher in rural area 17.35% than urban area 11.11%. The western regions were more affected with 12.69% than the central regions 10.57%. The prevalence was 14.66% in the boucle of Mouhoun region and 14.59 in the center-west region. Aggregate data were not available for the other regions.ConclusionsHBV has clearly an important burden in Burkina Faso as described by its high prevalence and this problem significantly challen

  Biostatistiques et épidémiologieImmunologieMaladies infectieuses et tropicalesLicence : Open Access http://creativecommons.org/licenses/by/4.0/ http://creativecommons.org/publicdomain/zero/1.0/ This article is distributed under the terms of the Creative Commons Attribution 4.0 International License (), which permits unrestricted use, distribution, and reproduction in any medium, provid

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  High Resolution Mapping of Soil Properties Using Remote Sensing Variables in South-Western Burkina Faso: A Comparison of Machine Learning and Multiple Linear Regression Models

  Accurate and detailed spatial soil information is essential for environmental modelling, risk assessment and decision making. The use of Remote Sensing data as secondary sources of information in digital soil mapping has been found to be cost effective and less time consuming compared to traditional soil mapping approaches. But the potentials of Remote Sensing data in improving knowledge of local scale soil information in West Africa have not been fully explored. This study investigated the use of high spatial resolution satellite data (RapidEye and Landsat), terrain/climatic data and laboratory analysed soil samples to map the spatial distribution of six soil properties–sand, silt, clay, cation exchange capacity (CEC), soil organic carbon (SOC) and nitrogen–in a 580 km2 agricultural watershed in south-western Burkina Faso. Four statistical prediction models–multiple linear regression (MLR), random forest regression (RFR), support vector machine (SVM), stochastic gradient boosting (SGB)–were tested and compared. Internal validation was conducted by cross validation while the predictions were validated against an independent set of soil samples considering the modelling area and an extrapolation area. Model performance statistics revealed that the machine learning techniques performed marginally better than the MLR, with the RFR providing in most cases the highest accuracy. The inability of MLR to handle non-linear relationships between dependent and independent variables was found to be a limitation in accurately predicting soil properties at unsampled locations. Satellite data acquired during ploughing or early crop development stages (e.g. May, June) were found to be the most important spectral predictors while elevation, temperature and precipitation came up as prominent terrain/climatic variables in predicting soil properties. The results further showed that shortwave infrared and near infrared channels of Landsat8 as well as soil specific indices of redness, co

  Santé publiqueLicence : Creative Commons Attribution License This is an open access article distributed under the terms of the, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

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  High seroprevalence of SARS-CoV-2 in Burkina-Faso, Ghana and Madagascar in 2021: a population-based study

  Nicole S. Struck, Eva Lorenz, Christina Deschermeier, Daniel Eibach, Jenny Kettenbeil, Wibke Loag, Steven A. Brieger, Anna M. Ginsbach, Christian Obirikorang, Oumou Maiga-Ascofare, Yaw Adu Sarkodie, Eric Ebenezer Amprofi Boham, Evans Asamoah Adu, Gracelyn Asare, Amos Amoako-Adusei, Alfred Yawson, Alexander Owusu Boakye, James Deke, Nana Safi Almoustapha, Louis Adu-Amoah, Ibrahim Kwaku Duah, Thierry A. Ouedraogo, Valentin Boudo, Ben Rushton, Christa Ehmen, Daniela Fusco, Leonard Gunga, Dominik Benke, Yannick Höppner, Zaraniaina Tahiry Rasolojaona, Tahinamandranto Rasamoelina, Rivo A. Rakotoarivelo, Raphael Rakotozandrindrainy, Boubacar Coulibaly, Ali Sié, Anthony Afum-Adjei Awuah, John H. Amuasi, Aurélia Souares, Jürgen May

  BackgroundThe current COVID-19 pandemic affects the entire world population and has serious health, economic and social consequences. Assessing the prevalence of COVID-19 through population-based serological surveys is essential to monitor the progression of the epidemic, especially in African countries where the extent of SARS-CoV-2 spread remains unclear.MethodsA two-stage cluster population-based SARS-CoV-2 seroprevalence survey was conducted in Bobo-Dioulasso and in Ouagadougou, Burkina Faso, Fianarantsoa, Madagascar and Kumasi, Ghana between February and June 2021. IgG seropositivity was determined in 2,163 households with a specificity improved SARS-CoV-2 Enzyme-linked Immunosorbent Assay. Population seroprevalence was evaluated using a Bayesian logistic regression model that accounted for test performance and age, sex and neighbourhood of the participants.ResultsSeroprevalence adjusted for test performance and population characteristics were 55.7% [95% Credible Interval (CrI) 49·0; 62·8] in Bobo-Dioulasso, 37·4% [95% CrI 31·3; 43·5] in Ouagadougou, 41·5% [95% CrI 36·5; 47·2] in Fianarantsoa, and 41·2% [95% CrI 34·5; 49·0] in Kumasi. Within the study population, less than 6% of participants performed a test for acute SARS-CoV-2 infection since the onset of the pandemic.ConclusionsHigh exposure to SARS-CoV-2 was found in the surveyed regions albeit below the herd immunity threshold and with a low rate of previous testing for acute infections. Despite the high seroprevalence in our study population, the duration of protection from naturally acquired immunity remains unclear and new virus variants continue to emerge. This highlights the importance of vaccine deployment and continued preventive measures to protect the population at risk.Supplementary InformationThe online version contains supplementary material available at 10.1186/s12889-022-13918-y.

  Biologie cellulaire et moléculaireGénétiqueBiostatistiques et épidémiologieLicence : Open Access http://creativecommons.org/licenses/by/4.0/ http://creativecommons.org/publicdomain/zero/1.0/ This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as

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  High stress related to COVID-19 among health workers in the Plateau Central healthcare region (BURKINA FASO): a cross-sectional study

  Solo Traoré, Désiré Lucien Dahourou, Boyo Constant Paré, Yemboado Diedonné Lompo, Wendlassida Josiane Kaboré, Wind-La-Sida Abd-El-Aziz Ouédraogo, Datouo Thomas Kambou, Wenddinda Rabbaly Adeline Salou, Delphin Kaboré, Abdoulaye Ouédraogo, Siaka Sia, Mady Zorné, Boezemwendé Ouoba, Oumar Guira

  BackgroundThe COVID-19 pandemic challenged the mental wellbeing of health workers. The objective of this study was to assess health workers' perceived stress during the response to COVID-19 in the Central Plateau region (Burkina Faso).MethodsWe conducted a cross-sectional study of health workers in the Central Plateau health region from September 20 to October 20, 2021. Agents' perceived stress was assessed by the Perceived Stress Scale (PSS-10). Factors associated with high stress (PSS-10 score ≥ 27) were identified by logistic regression.ResultsA total of 272 officers participated in the survey. The mean PSS-10 score was 29.3 points (standard deviation: 6.2). Three out of ten agents (68%) had a high level of stress. The main sources of stress were the risk of being exposed to contamination (70%) and being the source of contamination (78%). Working at the referral health center [adjusted odds ratio (aOR): 2.29; 95% confidence interval (95% CI): 1.19–4.41], the hospital as the main source of COVID-19 information (aOR: 1.17; 95% CI: 1.01-3.04), fear of COVID-19 patients being managed at one's center (aOR: 1.8; 95% CI: 1.06–3.07) were factors associated with high health worker stress levels during the first wave of COVID-19.ConclusionThe COVID-19 pandemic caused high stress among health care workers in Burkina Faso. Psychological support for health center workers in responding to future epidemics would improve their mental health.

  Biostatistiques et épidémiologieSanté publiqueLicence : This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journa

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  High-resolution African HLA resource uncovers HLA-DRB1 expression effects underlying vaccine response

  Alexander J. Mentzer, Alexander T. Dilthey, Martin Pollard, Deepti Gurdasani, Emre Karakoc, Tommy Carstensen, Allan Muhwezi, Clare Cutland, Amidou Diarra, Ricardo da Silva Antunes, Sinu Paul, Gaby Smits, Susan Wareing, HwaRan Kim, Cristina Pomilla, Amanda Y. Chong, Debora Y. C. Brandt, Rasmus Nielsen, Samuel Neaves, Nicolas Timpson, Austin Crinklaw, Cecilia S. Lindestam Arlehamn, Anna Rautanen, Dennison Kizito, Tom Parks, Kathryn Auckland, Kate E. Elliott, Tara Mills, Katie Ewer, Nick Edwards, Segun Fatumo, Emily Webb, Sarah Peacock, Katie Jeffery, Fiona R. M. van der Klis, Pontiano Kaleebu, Pandurangan Vijayanand, Bjorn Peters, Alessandro Sette, Nezih Cereb, Sodiomon Sirima, Shabir A. Madhi, Alison M. Elliott, Gil McVean, Adrian V. S. Hill, Manjinder S. Sandhu

  How human genetic variation contributes to vaccine effectiveness in infants is unclear, and data are limited on these relationships in populations with African ancestries. We undertook genetic analyses of vaccine antibody responses in infants from Uganda (n = 1391), Burkina Faso (n = 353) and South Africa (n = 755), identifying associations between human leukocyte antigen (HLA) and antibody response for five of eight tested antigens spanning pertussis, diphtheria and hepatitis B vaccines. In addition, through HLA typing 1,702 individuals from 11 populations of African ancestry derived predominantly from the 1000 Genomes Project, we constructed an imputation resource, fine-mapping class II HLA-DR and DQ associations explaining up to 10% of antibody response variance in our infant cohorts. We observed differences in the genetic architecture of pertussis antibody response between the cohorts with African ancestries and an independent cohort with European ancestry, but found no in silico evidence of differences in HLA peptide binding affinity or breadth. Using immune cell expression quantitative trait loci datasets derived from African-ancestry samples from the 1000 Genomes Project, we found evidence of differential HLA-DRB1 expression correlating with inferred protection from pertussis following vaccination. This work suggests that HLA-DRB1 expression may play a role in vaccine response and should be considered alongside peptide selection to improve vaccine design. Genome-wide analyses of vaccine antibody responses in 2,499 infants from Uganda, South Africa and Burkina Faso identify associations between specific HLA genes and response to eight vaccines, providing insights that could be considered for population-adjusted vaccine design strategies.

  Biologie cellulaire et moléculaireGénétiqueBiostatistiques et épidémiologieLicence : Open Access http://creativecommons.org/licenses/by/4.0/ This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original autho

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  High-resolution species assignment of Anopheles mosquitoes using k-mer distances on targeted sequences

  The ANOSPP amplicon panel is a genus-wide targeted sequencing panel to facilitate large-scale monitoring of Anopheles species diversity. Combining information from the 62 nuclear amplicons present in the ANOSPP panel allows for a more senstive and specific species assignment than single gene (e.g. COI) barcoding, which is desirable in the light of permeable species boundaries. Here, we present NNoVAE, a method using Nearest Neighbours (NN) and Variational Autoencoders (VAE), which we apply to k-mers resulting from the ANOSPP amplicon sequences in order to hierarchically assign species identity. The NN step assigns a sample to a species-group by comparing the k-mers arising from each haplotype’s amplicon sequence to a reference database. The VAE step is required to distinguish between closely related species, and also has sufficient resolution to reveal population structure within species. In tests on independent samples with over 80% amplicon coverage, NNoVAE correctly classifies to species level 98% of samples within the An. gambiae complex and 89% of samples outside the complex. We apply NNoVAE to over two thousand new samples from Burkina Faso and Gabon, identifying unexpected species in Gabon. NNoVAE presents an approach that may be of value to other targeted sequencing panels, and is a method that will be used to survey Anopheles species diversity and Plasmodium transmission patterns through space and time on a large scale, with plans to analyse half a million mosquitoes in the next five years.

  Biologie cellulaire et moléculaireGénétiqueBiostatistiques et épidémiologieLicence : Creative Commons Attribution License This article is distributed under the terms of the, which permits unrestricted use and redistribution provided that the original author and source are credited.

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  High-spatial resolution epidemic surveillance of bacterial meningitis in the African meningitis belt in Burkina Faso

  Maxime Woringer, Souleymane Porgho, Christophe Fermanian, Nadège Martiny, Avner Bar-Hen, Judith E. Mueller

  Despite improved surveillance capacities and WHO recommendations for subdistrict analysis, routine epidemic surveillance of acute bacterial meningitis in the African meningitis belt remains largely limited to the district level. We evaluated the appropriateness and performance of analyses at higher spatial resolution. We used suspected meningitis surveillance data at health centre (HC) resolution from Burkina Faso from 14 health districts spanning years 2004–2014 and analysed them using spatio-temporal statistics and generative models. An operational analysis compared epidemic signals at district and HC-level using weekly incidence thresholds. Eighty-four percent (N = 98/116) of epidemic clusters spanned only one HC-week. Spatial propagation of epidemic clusters was mostly limited to 10–30 km. During the 2004–2009 (with serogroup A meningitis) and 2010–2014 (after serogroup A elimination) period, using weekly HC-level incidence thresholds of 100 and 50 per 100,000 respectively, we found a gain in epidemic detection and timeliness in 9 (41% of total) and 10 (67%), respectively, district years with at least one HC signal. Individual meningitis epidemics expanded little in space, suggesting that a health centre level analysis is most appropriate for epidemic surveillance. Epidemic surveillance could gain in precision and timeliness by higher spatial resolution. The optimal threshold should be defined depending on the current background incidence of bacterial meningitis.

  Biostatistiques et épidémiologieMicrobiologie (bactériologie, virologie)Maladies infectieuses et tropicalesLicence : Open Access http://creativecommons.org/licenses/by/4.0/ This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original autho

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  Higher gametocyte production and mosquito infectivity in chronic compared to incident Plasmodium falciparum infections

  Aissata Barry, John Bradley, Will Stone, Moussa W. Guelbeogo, Kjerstin Lanke, Alphonse Ouedraogo, Issiaka Soulama, Issa Nébié, Samuel S. Serme, Lynn Grignard, Catriona Patterson, Lindsey Wu, Jessica J. Briggs, Owen Janson, Shehu S. Awandu, Mireille Ouedraogo, Casimire W. Tarama, Désiré Kargougou, Soumanaba Zongo, Sodiomon B. Sirima, Matthias Marti, Chris Drakeley, Alfred B. Tiono, Teun Bousema

  Plasmodium falciparum gametocyte kinetics and infectivity may differ between chronic and incident infections. In the current study, we assess parasite kinetics and infectivity to mosquitoes among children (aged 5–10 years) from Burkina Faso with (a) incident infections following parasite clearance (n = 48) and (b) chronic asymptomatic infections (n = 60). In the incident infection cohort, 92% (44/48) of children develop symptoms within 35 days, compared to 23% (14/60) in the chronic cohort. All individuals with chronic infection carried gametocytes or developed them during follow-up, whereas only 35% (17/48) in the incident cohort produce gametocytes before becoming symptomatic and receiving treatment. Parasite multiplication rate (PMR) and the relative abundance of ap2-g and gexp-5 transcripts are positively associated with gametocyte production. Antibody responses are higher and PMR lower in chronic infections. The presence of symptoms and sexual stage immune responses are associated with reductions in gametocyte infectivity to mosquitoes. We observe that most incident infections require treatment before the density of mature gametocytes is sufficient to infect mosquitoes. In contrast, chronic, asymptomatic infections represent a significant source of mosquito infections. Our observations support the notion that malaria transmission reduction may be expedited by enhanced case management, involving both symptom-screening and infection detection. In this longitudinal study of an incident (new infections) and chronic (asymptomatic infections) cohort of Plasmodium falciparum infection in children in Burkina Faso, the authors show higher gametocyte production and mosquito infectivity in chronic infections.

  Biostatistiques et épidémiologieParasitologie et mycologieImmunologieLicence : Open Access http://creativecommons.org/licenses/by/4.0/ This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original autho

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  Histiocytose langerhansienne cérébrale

  Assou Ajja, Rachid Ammor

  Licence : The Pan African Medical Journal - ISSN 1937-8688. This is an Open Access article distributed under the terms of the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

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