7 research outputs found
Impact of pre-analytical factors on mycobacterium cultures contaminations rates in Burkina Faso, West Africa
Introduction: for a high quality level diagnosis, mycobacterium culture must comply with the pre-analytical and analytical conditions recommended by the WHO and the country National Tuberculosis Program (NTP). In this study, we determined whether temperature and duration of sputum storage were associated with culture contamination in Burkina Faso.
Methods: sputa were collected in 5 districts labs in Burkina Faso. Temperature and duration of sputum storage were recorded. After the collection, sputa were decontaminated using Petroff modified method, and the pellet was inoculated on LJ media and LJ media supply with 2% sodium pyruvate. Risk of culture contamination associated with temperature and duration of sputum storage was measured by Chi2 test and logistic regression.
Results: out of 404 specimens, 61% (246/404) were stored between 2 and 8°C, and 15% (61/404) were processed within three days. The global contamination rate was 24%, with only 8% for samples respecting WHO recommendations, up to 35% for others. Storage at room temperature was associated with a significantly higher risk of contamination compared to storage at 2-8°C (OR 2.24, p=0.001, IC 95%).
Conclusion: the recommendations about the temperature and the duration of sputum storage before cultures are not completely respected. This leads to high contamination rate of mycobacterium culture. It will be necessary to take logistics measures in peripherals health services or to develop more selective medium for mycobacterium culture in low income countries
Helminth exposure and immune response to the two-dose heterologous Ad26.ZEBOV, MVA-BN-Filo Ebola vaccine regimen
International audienceBACKGROUND: The exposure to parasites may influence the immune response to vaccines in endemic African countries. In this study, we aimed to assess the association between helminth exposure to the most prevalent parasitic infections, schistosomiasis, soil transmitted helminths infection and filariasis, and the Ebola virus glycoprotein (EBOV GP) antibody concentration in response to vaccination with the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen in African and European participants using samples obtained from three international clinical trials. METHODS/PRINCIPAL FINDINGS: We conducted a study in a subset of participants in the EBL2001, EBL2002 and EBL3001 clinical trials that evaluated the Ad26.ZEBOV, MVA-BN-Filo vaccine regimen against EVD in children, adolescents and adults from the United Kingdom, France, Burkina Faso, Cote d'Ivoire, Kenya, Uganda and Sierra Leone. Immune markers of helminth exposure at baseline were evaluated by ELISA with three commercial kits which detect IgG antibodies against schistosome, filarial and Strongyloides antigens. Luminex technology was used to measure inflammatory and activation markers, and Th1/Th2/Th17 cytokines at baseline. The association between binding IgG antibodies specific to EBOV GP (measured on day 21 post-dose 2 and on Day 365 after the first dose respectively), and helminth exposure at baseline was evaluated using a multivariable linear regression model adjusted for age and study group. Seventy-eight (21.3%) of the 367 participants included in the study had at least one helminth positive ELISA test at baseline, with differences of prevalence between studies and an increased prevalence with age. The most frequently detected antibodies were those to Schistosoma mansoni (10.9%), followed by Acanthocheilonema viteae (9%) and then Strongyloides ratti (7.9%). Among the 41 immunological analytes tested, five were significantly (p < .003) lower in participants with at least one positive helminth ELISA test result: CCL2/MCP1, FGFbasic, IL-7, IL-13 and CCL11/Eotaxin compared to participants with negative helminth ELISA tests. No significant association was found with EBOV-GP specific antibody concentration at 21 days post-dose 2, or at 365 days post-dose 1, adjusted for age group, study, and the presence of any helminth antibodies at baseline. CONCLUSIONS/SIGNIFICANCE: No clear association was found between immune markers of helminth exposure as measured by ELISA and post-vaccination response to the Ebola Ad26.ZEBOV/ MVA-BN-Filo vaccine regimen. TRIAL REGISTRATION: NCT02416453, NCT02564523, NCT02509494. ClinicalTrials.gov
Socio-demographic informations about hosts and <i>M. bovis</i> isolates.
a<p>specific to human hosts,</p>b<p>bovine study,</p>c<p>nationwide survey,</p>d<p>regional study.</p><p>Socio-demographic informations about hosts and <i>M. bovis</i> isolates.</p
Allelic diversity of the 26 MIRU-VNTR loci in <i>M. bovis</i> isolates from humans and livestock in Burkina Faso.<sup>*</sup>
<p>*Excluding one strain of the putative African 5 clonal complex that hasn't MIRU-VNTR data.</p><p>Af1 = African 1 clonal complex, Af5 = putative African 5 clonal complex.</p><p>Allelic diversity of the 26 MIRU-VNTR loci in <i>M. bovis</i> isolates from humans and livestock in Burkina Faso.<sup><a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003142#nt108" target="_blank">*</a></sup></p
UPGMA tree based on the MIRU-VNTR (26 loci) and spoligotyping data.
<p>1, SB number = name of spoligotype based on <a href="http://www.Mbovis.org" target="_blank">http://www.Mbovis.org</a> database nomenclature; 2, RDAf1 = Genomic deletion specific to Af1 clonal complex; 3, The MIRU-VNTR patterns are detailed in <a href="http://www.plosntds.org/article/info:doi/10.1371/journal.pntd.0003142#pntd-0003142-t002" target="_blank">table 2</a>.</p
Spoligotypes, MIRU-VNTR patterns and clonal complex identification of the <i>M. bovis</i> strains isolated in Burkina Faso.
1<p><b>▪</b>, presence of spacer; <b>□</b>, absence of spacer.</p>2<p>MIRU-VNTR loci: ETR A, ETR B, ETR C, ETR D, ETR E, QUB-11a, QUB-11b, QUB-3232, QUB-26, QUB-4156, MIRU 2, MIRU 10, MIRU 16, MIRU 20, MIRU 23, MIRU 24, MIRU 26, MIRU 27, MIRU 39, MIRU 40, Mtub 04, Mtub 21, Mtub 29, Mtub 30, Mtub 34, Mtub 39. NA = Not Available.</p>3<p>Af1 = African 1 clonal complex, Af5 = putative African 5 clonal complex.</p><p>Spoligotypes, MIRU-VNTR patterns and clonal complex identification of the <i>M. bovis</i> strains isolated in Burkina Faso.</p