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To overcome the extensive polymorphism found in human Plasmodium antigens and to avoid the lengthy characterization of their 3 dimensional structure and subsequent production of the native proteins we have been concentrated in large unstructured, non-or low-polymorphic fragments present in the blood stage of P. falciparum. Three fragments derived from the 2 family-specific and constant regions of merozoite surface protein (MSP2) and PFF0165c protein were previously selected for evaluation as potential single vaccine candidates. In order to increase and optimize their potential efficacy against P. falciparum infection the 3 antigens were combined in a single DNA recombinant product (FusN) and compared its antigenicity with that of single antigens in sera of volunteers living in endemic countries. Immunogenicity of the FusN was then compared with that of the mixture of 3 antigens in 3 strains of mice. Antigen specific, affinity purified human antibodies were then tested in antibody dependent cellular inhibition and merozoite opsonization assays. In addition, the antigen specific antibody response and its association with protection from malaria infection were determined. The data collected indicate that the recombinant product is an equal or better antigen /immunogen than fragments used either alone or as a mixture for vaccination in combination with adjuvant. In addition, antibody response to FusN shows a stronger association with protection than single fragments. The use of a single construct as vaccine would drastically reduce the cost of manufacturing and development of the GMP product.

Objective: To investigate 4 combinations of mutations responsible for glucose-6-phosphate dehydrogenase (G6PD) deficiency in a rural community of Burkina Faso, a malaria endemic country. Methods: Two hundred individuals in a rural community were genotyped for the mutations A376G, G202A, A542T, G680T and T968C using TaqMan single nucleotide polymorphism assays and polymerase chain reaction followed by restriction fragment length polymorphism. Results: The prevalence of the G6PD deficiency was 9.5% in the study population. It was significantly higher in men compared to women (14.3% vs 6.0%, P=0.049). The 202A/376G G6PD A- was the only deficient variant detected. Plasmodium falciparum asymptomatic parasitaemia was significantly higher among the G6PD-non-deficient persons compared to the G6PD-deficient (P

Introduction : L'infection par Helicobacter pylori constitue un probleme de sante publique notamment dans les pays en developpement. Elle entraine une gastrite pouvant evoluer vers des formes severes d'ulceration et de transformation maligne. La presente etude avait pour objectif de diagnostiquer H. pylori par des techniques serologique et moleculaire au Burkina Faso. Methodes : L'etude prospective a ete conduite de mars a juin 2012 sur 70 patients venus en consultation dans le service de gastroenterologie au Centre Medical Saint Camille. Le diagnostic de H. pylori a ete realise par le test ELISA Immunocomb (ORGENICS Ltd, Yavne, Israel) et la PCR sur des biopsies gastriques prelevees sur les patients. Resultats : Les pathologies gastroduodenales etaient plus frequentes chez les patients de plus de 45 ans. Les prevalences de H. pylori etaient respectivement de 88,57% et de 91,43% par serologie Immunocomb et par PCR. La difference entre les deux techniques n'etait pas significative (P = 0,573). La performance de la PCR a ete comparee a celle de la technique Immunocomb. Les resultats montrent une sensibilite et une specificite de 92,2% et 50,0% pour la technique Immunocomb. Conclusion : Le diagnostic de H. pylori par PCR est plus specifique que le test serologique Immunocomb et devrait etre introduit dans le diagnostic de routine de cette bacterie pathogene au Burkina Faso.

HCV and HBV cause annually, 2000 deaths from liver cancer in Burkina Faso. In this country, serological screening of hepatitis viruses B and C is only systematic among blood donors. The aims of this study were; (1) to investigate the reasons for the prescription of the screening for hepatitis B and C; (2) to determine HCV and HBV prevalence among 462 patients attending the Saint Camille Centre and (3) to identify patients with acute hepatitis or with chronic hepatitis for better monitoring. From February to May 2012, 462 patients attending the laboratory of the Saint Camille Medical Centre with viral hepatitis suspicion were screened. The hepatitis B and C serological markers were detected through Enzyme Immuno Assay (EIA) technique using commercial reagent kits. The clinical symptoms were also recorded for each patient. The results revealed that, the main clinical symptoms that prompted physicians to request HBV and HCV screenings were: asthenia (39.4%), anorexia (21.2%), abdominal pains (19.0%), nausea (10.4%), others (10.0%). The prevalence of HbsAg was 29.4% among the screened people. Patients with acute hepatitis B, active chronic hepatitis B and non-active chronic hepatitis B represented 11.2, 2.2 and 16.0%, respectively. The acquisition of immunity against HBV after vaccination was attempted for 11.7% people. HCV prevalence was 3.9% and its coinfection with HBV was 2.2%. This study showed a high prevalence for hepatitis B and C among patients attending Saint Camille Medical Centre. Without hygiene education and HBV/HCV prevention, viral hepatitis infection will become a serious public health problem in Burkina Faso.

Journal de Gynecologie Obstetrique et Biologie de la Reproduction - Vol. 40 - N° 7 - p. 633-638

BACKGROUND AND OBJECTIVE: The high prevalence of numerous transfusion-transmitted infectious diseases such as HIV HBV HCV and syphilis in sub-Saharan Africa affects blood safety for transfusion recipients. The aim of this study was to evaluate the prevalence and incidence of transfusion-transmissible infectious diseases among blood donors in Burkina Faso. METHODS: A retrospective study of blood donors records from January to December 2009 was conducted. Prevalence and incidence of viral infections were calculated among repeat and first-time blood donors. RESULTS: Of the total of 31405 first-time volunteer blood donors in 2009 24.0% were infected with at least one pathogen and 1.8% had serological evidence of multiple infections. The seroprevalence of HIV HBV HCV and syphilis in first-time volunteer donors was 1.8% 13.4% 6.3% and 2.1% respectively. In 3981 repeat donors the incidence rate was 3270.2 5874.1 and 6784.6 per 100000 donations for anti-HIV-1 HBsAg and anti-HCV respectively. These numbers varied significantly according to populations where blood is collected and blood centres in Burkina Faso. CONCLUSION: The relatively high prevalence of viral markers in first-time volunteers and remarkably high incidence of infections in repeat donors raise concerns regarding the safety of these donors and suggest that implementation of NAT might significantly improve the situation. (c) 2011 Blackwell Publishing Ltd.

OBJECTIVE: To determine hepatitis C virus (HCV) prevalence and the rate of HCV/human immunodeficiency virus (HIV) co-infection in pregnant women attending Saint Camille medical centre (SCMC) in Ouagadougou. METHODS: A total of 607 pregnant women 16-45 years old with

A longitudinal study was undertaken in Burkina Faso among 293 children aged 6 months to 9 years in order to determine the correlation between an antibody response to several individual malarial antigens and malarial infection. It was found that the presence of a positive antibody response at the beginning of the rainy season to three long synthetic peptides corresponding to Plasmodium falciparum Exp-1 101-162, MSP-3 154-249 and GLURP 801-920 but not to CSP 274-375 correlated with a statistically significant decrease in malarial infection during the ongoing transmission season. The simultaneous presence of an antibody response to more than one antigen is indicative of a lower frequency of malarial infection. This gives scientific credibility to the notion that a successful malaria vaccine should contain multiple antigens.

Background : Vertical human immunodeficiency virus (HIV) transmission is a public health problem in Burkina Faso. The main objective of this study on the prevention of mother-to-child HIV-1 transmission was to determine the residual risk of HIV transmission in infants born to mothers receiving highly active antiretroviral therapy (HAART). Moreover, we detect HIV antiretroviral (ARV) drug resistance among mother–infant pairs and identify subtypes and circulating recombinant forms (CRF) in Burkina Faso. Design : In this study, 3,215 samples of pregnant women were analyzed for HIV using rapid tests. Vertical transmission was estimated by polymerase chain reaction in 6-month-old infants born to women who tested HIV positive. HIV-1 resistance to ARV, subtypes, and CRFs was determined through ViroSeq kit using the ABI PRISM 3,130 sequencer. Results : In this study, 12.26% (394/3,215) of the pregnant women were diagnosed HIV positive. There was 0.52% (2/388) overall vertical transmission of HIV, with rates of 1.75% (2/114) among mothers under prophylaxis and 0.00% (0/274) for those under HAART. Genetic mutations were also isolated that induce resistance to ARV such as M184V, Y115F, K103N, Y181C, V179E, and G190A. There were subtypes and CRF of HIV-1 present, the most common being: CRF06_CPX (58.8%), CRF02_AG (35.3%), and subtype G (5.9%). Conclusions : ARV drugs reduce the residual rate of HIV vertical transmission. However, the virus has developed resistance to ARV, which could limit future therapeutic options when treatment is needed. Resistance to ARV therefore requires a permanent interaction between researchers, physicians, and pharmacists, to strengthen the network of monitoring and surveillance of drug resistance in Burkina Faso. Keywords : pregnant women; HAART; sequencing; genotypes; mutations (Published: 27 January 2015) Citation : Glob Health Action 2015, 8 : 26065 - http://dx.doi.org/10.3402/gha.v8.26065

Summary The present work describes the recognition of three synthetic polypeptides encompassing the N- and C-terminal regions of the transmembrane Exp-1 protein of the parasite Plasmodium falciparum by plasma and peripheral blood mononuclear cells from naturally exposed individuals living in African endemic areas. The three polypeptides comprise the sequences 23–105, 73–162 and 101–162, and overlap at the transmembrane domain (73–105). Thus, they permitted characterization of the immune response specific to the N- and C-terminal domains in an independent fashion. Two different populations were evaluated, one in the village of Safo in Mali and the other in the villages of Somnaway, Kabortenga and Toussouktenga in Burkina Faso. Antibodies to the sequence 73–162 of Pf Exp-1 were found in 70% of adult Mali donors and in all of the donors tested from Burkina Faso. Strikingly, the N-terminal fragment Pf Exp-1 23–105 was only weakly recognized by a few donors. Evaluation of the T-cell response indicated that the peptide Pf Exp-1 23–105 was more potent than Pf Exp-1 73–162 in inducing a proliferative response. A correlation between peptide-specific interferon-γ and interleukin-6 production and proliferation to peptide Pf Exp-1 23–105 was observed. Further studies are needed to evaluate this molecule as a vaccine candidate.

Protein α-helical coiled coil structures that elicit antibody responses, which block critical functions of medically important microorganisms, represent a means for vaccine development. By using bioinformatics algorithms, a total of 50 antigens with α-helical coiled coil motifs orthologous to Plasmodium falciparum were identified in the P. vivax genome. The peptides identified in silico were chemically synthesized; circular dichroism studies indicated partial or high α-helical content. Antigenicity was evaluated using human sera samples from malaria-endemic areas of Colombia and Papua New Guinea. Eight of these fragments were selected and used to assess immunogenicity in BALB/c mice. ELISA assays indicated strong reactivity of serum samples from individuals residing in malaria-endemic regions and sera of immunized mice, with the α-helical coiled coil structures. In addition, ex vivo production of IFN-γ by murine mononuclear cells confirmed the immunogenicity of these structures and the presence of T-cell epitopes in the peptide sequences. Moreover, sera of mice immunized with four of the eight antigens recognized native proteins on blood-stage P. vivax parasites, and antigenic cross-reactivity with three of the peptides was observed when reacted with both the P. falciparum orthologous fragments and whole parasites. Results here point to the α-helical coiled coil peptides as possible P. vivax malaria vaccine candidates as were observed for P. falciparum. Fragments selected here warrant further study in humans and non-human primate models to assess their protective efficacy as single components or assembled as hybrid linear epitopes.

Background Two long synthetic peptides representing the dimorphic and constant C-terminal domains of the two allelic families of Plasmodium falciparum merozoite surface proteins 2 are considered promising malaria vaccine candidates. The aim of the current study is to characterize the immune response (epitope mapping) in naturally exposed individuals and relate immune responses to the risk of clinical malaria. Methods To optimize their construction, the fine specificity of human serum antibodies from donors of different age, sex and living in four distinct endemic regions was determined in ELISA by using overlapping 20 mer peptides covering the two domains. Immune purified antibodies were used in Western blot and immunofluorescence assay to recognize native parasite derivate proteins. Results Immunodominant epitopes were characterized, and their distribution was similar irrespective of geographic origin, age group and gender. Acquisition of a 3D7 family and constant region-specific immune response and antibody avidity maturation occur early in life while a longer period is needed for the corresponding FC27 family response. In addition, the antibody response to individual epitopes within the 3D7 family-specific region contributes to protection from malaria infection with different statistical weight. It is also illustrated that affinity-purified antibodies against the dimorphic or constant regions recognized homologous and heterologous parasites in immunofluorescence and homologous and heterologous MSP2 and other polypeptides in Western blot. Conclusion Data from this current study may contribute to a development of MSP2 vaccine candidates based on conserved and dimorphic regions thus bypassing the complexity of vaccine development related to the polymorphism of full-length MSP2. Electronic supplementary material The online version of this article (doi:10.1186/1475-2875-13-510) contains supplementary material, which is available to authorized users.

To determine hepatitis C virus (HCV) prevalence and the rate of HCV/human immunodeficiency virus (HIV) co-infection in pregnant women attending Saint Camille medical centre (SCMC) in Ouagadougou.A total of 607 pregnant women, 16-45 years old, with32 weeks amenorrhoea were screened for HCV and HIV using rapid tests. The majority of the women included in the study were previously known as HIV infected, as the centre is a reference centre for the programme of prevention against mother-to-child HIV transmission in the country. HCV RNA was extracted and quantified using the cDNA polymerase chain reaction with the nested primers at the 5' untranslated region. Transaminases were measured from plasma samples using spectrophotometric method.Of women, 62.27% were infected with HIV. The prevalence of HCV was 2.14% in the screened pregnant women: 1.75% in HIV-negative women and 2.38% in HIV-positive ones. This prevalence is not significantly different between HIV-positive and HIV-negative pregnant women (P = 0.81). HCV RNA was found in all women with anti-HCV. A significant transaminase increase was noted in women infected with HCV (P = 0.01 and P0.01 for glutamic-pyruvic transaminase and glutamic-oxaloacetic transaminase, respectively). Risk factors significantly associated with HCV positivity in pregnant women included transfusion and genital excision. In addition, the infection was linked with the educational level of the women.The issue of this study revealed that effort should be made to promote safe medical practices and fight against women genital excision that are found to be the main risk factors associated with the HCV infection.

OBJECTIVE: To evaluate efficiency of HAART in the prevention of mother to child HIV transmission. METHODS: A longitudinal study was conducted on 1 300 women attending the antenatal service at Saint Camille Medical Centre from September 2010 to July 2011. The HIV status of mothers was determined by rapid tests and ELISA. Discordant results were confirmed by real-time PCR. PCR was used to determine HIV status of children born from HIV-positive mothers. RESULTS: Among 1 300 pregnant women tested for HIV 378 were seropositive. Mothers were predominantly housewives (69.7%) and their mean age was (28.32+/-0.15) years. The overall prevalence of HIV transmission from mother to child was 4.8% (18/378). This prevalence differed significantly from 0.0% (0/114) to 6.8% (18/264) in children born from mothers under HAART and those with mothers under New Prophylactic Protocol (AZT + 3TC + NVP) respectively (P< 0.01). Childrens mortality rate during the medical follow up was 1.3% (5/378). Among 16 women with HIV dubious status by ELISA the Real Time PCR confirmed 2/16 (12.5%) as HIV positive. CONCLUSIONS: The protocol of prevention of mother to children HIV transmission (PMTCT) is effective. The rate of HIV vertical transmission is significantly reduced. Early diagnosis determined by PCR of children born from HIV-positive mother is necessary and recommended in the context of PMTCT in Burkina Faso. We also found that PCR is an effective tool to confirm HIV status in pregnant women. Copyright (c) 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

Results In this study, 12.26% (394/3215) of the pregnant women were diagnosed HIV-positive, 0.52% (2/388) overall residual rate of transmission was identified with rates of 1.75% (2/114) among mothers under prophylaxis and 0.00% (0/274) for those under HAART. Genetic mutations have also been isolated that induce resistance to ARVs like M184V, Y115F, K103N, Y181C, v179E, G190A, etc. And there were subtypes and circulating recombinant forms (CRF) of HIV-1 such as: CRF06_CPX (58.8%), CRF02_AG (35.3%) and subtype G (5.9%). Conclusion Antiretroviral drugs reduce the residual rate of HIV vertical transmission. However, they cause mutations that induce resistance of HIV to antiretroviral therapy. Resistance to ARV therefore requires a permanent dialogue between clinicians, prescribers, pharmacists, and the creation of a network of monitoring and surveillance of drug resistance in Burkina Faso.