Additional Haplogroups of Toxoplasma gondii out of Africa: Population Structure and Mouse-Virulence of Strains from Gabon

Prevalence of human toxoplasmosis in tropical African countries usually exceeds 50%. Its role as a major opportunistic infection of AIDS patients is regularly described. Due to the lack of investigation, congenital infection is certainly underestimated in Africa. Incidence of Toxoplasma ocular disease is higher in Africa and South America than in Europe. Severe cases in immunocompetent patients were described after infection acquired in Amazonia, but nothing is known about such cases in Africa. Several studies argued for a role of genotypes in the clinical expression of human toxoplasmosis, and for a geographical structuration of Toxoplasma across continents. Genetic data concerning isolates from Africa are scarce. Here, apart from the worldwide Type III, we described two main haplogroups, Africa 1 and 3. We detected genetic exchanges between urban centers favored by trade exchange and transportation. It shows how important human influence is, even in shaping the genetic structure of a zoonotic disease agent. Finding of identical haplogroups in South America suggested that these African and American strains share a common ancestor. As a higher pathogenicity in human of South American genotypes has been described, this similarity of genotypes should encourage further clinical studies with genotype analysis in Africa

Indication and Outcomes of Paediatric Blood Transfusion at Three Hospitals in Gabon, Africa

Introduction: Blood transfusion is a life-saving treatment for severely anaemic children both in developed and developing countries. In this study we describe transfusions in paediatric settings of Gabon, Africa including clinical indications and subsequent outcomes.Methods: This prospective descriptive study was conducted in the cities of Libreville and Lambaréné from 1 January to 30 September 2016.Children between the ages of 1 month and 15 years, who were hospitalised and transfused were included in the study.Results: We included 287 children who represented 17.1% of all hospitalised children. The male:female ratio was 0.95 and the average age was 3.7 years. Packed red blood cells (PRBC) were administered to 99.3% of anaemic patients. World Health Organization (WHO) defined severe anaemia (haemoglobin (Haemoglobin) <7 g/dL) was the main indication (95.1%) with the mean haemoglobin (Hb) level pretransfusion being 5.1 g/dL ± 2.7 g/dL, and post-transfusion haemoglobin gain being 2.9 g/dL ± 1.2 g/dL. Malaria was present in 79% of transfused patients and 46.9% of children screened were homozygous for sickle cell disease. No post-transfusion incident was reported although reporting may have been incomplete.Conclusion: Blood transfusion is frequent in our context; the clinical outcome is mostly favourable. French Title: Indication et Résultats de la Transfusion Sanguine Pédiatrique Dans Trois Hôpitaux au Gabon, en Afrique Introduction: La transfusion sanguine est un traitement salvateur pour les enfants gravement anémiés dans les pays développés ou endéveloppement. Dans cette étude, nous décrivons les transfusions en milieu pédiatrique du Gabon, en Afrique, y compris les indicationscliniques et les résultats.Méthodes: Cette étude descriptive prospective a été réalisée dans les villes de Libreville et Lambaréné du 1er janvier au 30 septembre 2016.Les enfants âgés de 1 mois à 15 ans, hospitalisés et transfusés ont été inclus dans l'étude.Résultats: Nous avons inclus 287 enfants qui représentaient 17.1% de tous les enfants hospitalisés. Le rapport garçons/filles était de 0.95 etl'âge moyen était de 3.7 ans. Des concentrés de globules rouges (CGR) ont été administrés à 99.3% des patients anémiques. L’anémie définiepar l’Organisation Mondiale de la Santé (OMS) (hémoglobine <7 g/dL) était la principale indication (95.1%), le taux moyen d'hémoglobine(Hb) avant transfusion étant de 5.1 g/dL ± 2.7 g/dL, et le gain d'hémoglobine après transfusion était de 2.9 g/dL ± 1.2 g/dL. Le paludisme étaitprésent chez 79% des patients transfusés et 46.9% des enfants dépistés étaient homozygotes pour la drépanocytose. Aucun incident post transfusionnel n'a été signalé, bien que le signalement ait pu être incomplet.Conclusion: La transfusion sanguine est fréquente dans notre contexte; l'issue clinique est généralement favorable. &nbsp

Genetic diversity of Plasmodium falciparum isolates from Baka Pygmies and their Bantu neighbours in the north of Gabon

Background: There have been many reports on the population genetic structure of Plasmodium falciparum from different endemic regions especially sub-Saharan Africa. However, few studies have been performed on neglected populations, such as the Pygmy populations. In this study, the population genetic structure of P. falciparum was investigated in the Baka Pygmies of Gabon and compared to that observed in neighboring villages composed mostly of Bantu farmers. Methods: A total of 342 blood samples were collected from 170 Baka Pygmies and 172 Bantus in the north of Gabon (Woleu Ntem Province). Plasmodium infections were characterized by sequencing a portion of the parasite cytochrome b gene. Population genetic structure of P. falciparum in the different villages was analysed using microsatellite markers and genes coding for antigenic proteins (MSP1, MSP2, GLURP, and EBA-175). Results: Overall, prevalence of P. falciparum was around 57 % and no significant difference of prevalence was observed between Pygmies and Bantus. No significant differences of population genetic structure of P. falciparum was found between Pygmy and Bantu people except for one antigen-coding gene, glurp, for which genetic data suggested the existence of a potentially disruptive selection acting on this gene in the two types of populations. The genetic structure of P. falciparum followed a pattern of isolation by distance at the scale of the study. Conclusion: The prevalence and genetic diversity of P. falciparum observed in Baka demonstrates a significant transmission of the parasite in this population, and some exchanges of parasites with Bantu neighbours. Despite that, some antigen-coding genes seem to have had a particular evolutionary trajectory in certain Pygmy populations due to specific local human and/or mosquito characteristics

Molecular analysis of human Papillomavirus detected among women positive for cervical lesions by visual inspection with acetic acid/Lugol's iodine (VIA/VILI) in Libreville, Gabon

Background: The human papillomavirus (HPV) is the causative agent of cervical cancer, which is the leading cancer-related cause of death for women in Sub-Saharan Africa. In 2013, the Gabonese Ministry of Health and the Sylvia Bongo Ondimba Foundation implemented cervical cancer screening programs based on the detection of cancerous lesions by visual inspection with acetic acid and/or Lugol's iodine (VIA/VILI). This pilot study was set up to determine the HPV profile and analyze the nucleotide sequence variation of HPV16 circulating in patients with cervical abnormalities detected by VIA/VILI testing. Methods: The cervical abnormalities observed upon VIA/VILI were confirmed by liquid-based cytology for all tested women. Nested PCR using the MY09/11 and GP5+/6+ primer sets was used to detect HPVs present in the extracted DNA. HPV genotypes were determined after sequencing of amplicons based on a high-throughput sequencing approach. For isolates of the HPV16 genotype, the E6 gene and the long control region (LCR) were directly sequenced using Sanger method. Results: The study included 87 women who showed a positive VIA/VILI result. Cervical abnormalities were found in 40.23 % of women and 40 % were classified as high-grade lesions. The HPV detection rate was 82.9 % among women with abnormal cytology. Among all the identified high-risk HPV genotypes, HPV16, 18 and 33 were the most frequent. Multiple HPV infections were observed in 42.31 % of HPV-infected women. Analysis of the HPV16 sequence variation in the E6 gene and in the LCR showed that 85.3 and 14.7 % belonged to the African and European lineages, respectively. Among the African branch variants, Af2 was the most frequently identified in this study. Conclusion: This study offers the first report of the HPV detection rate and molecular epidemiology among Gabonese women with a positive result in a VIA/VILI screening test. Moreover, data on the HPV16 sequence variation confirm the predominance of African variants in high-grade lesions