Synergistic activity of antibiotics combined with ivermectin to kill body lice

International audienceIvermectin and doxycycline have been found to be independently effective in killing body lice. In this study, 450 body lice were artificially fed on a Parafilm TM membrane with human blood associated with antibiotics (doxycycline, erythromycin, rifampicin and azithromycin) alone and in combination with ivermectin. Fluorescence in situ hybridisation and spectral deconvolution were performed to evaluate bacterial transcriptional activity following antibiotic intake by the lice. In the first series, a lethal effect of antibiotics on lice was observed compared with the control group at 18 days (log-rank test, P ≤ 10 −3), with a significant difference between groups in the production of nits (P = 0.019, Kruskal–Wallis test). A high lethal effect of ivermectin alone (50 ng/mL) was observed compared with the control group (log-rank test, P ≤ 10 −3). Fluorescence of bacteriocytes in lice treated with 20 ␮g/mL doxycycline was lower than in untreated lice (P < 0.0001, Kruskal–Wallis test). In the second series with antibiotic–ivermectin combinations , a synergistic lethal effect on treated lice (log-rank test, P < 10 −6) was observed compared with the control group at 18 days, associated with a significant decrease in the production of nits (P ≤ 0.001, Kruskal–Wallis test). Additionally, survival of lice in the combination treatment groups compared with ivermectin alone was significant (log-rank test, P = 0.0008). These data demonstrate that the synergistic effect of combinations of antibiotics and ivermectin could be used to achieve complete eradication of lice and to avoid selection of a resistant louse population

BMJ Open

In low-income settings with limited access to diagnosis, COVID-19 information is scarce. In September 2020, after the first COVID-19 wave, Mali reported 3086 confirmed cases and 130 deaths. Most reports originated from Bamako, with 1532 cases and 81 deaths (2.42 million inhabitants). This observed prevalence of 0.06% appeared very low. Our objective was to estimate SARS-CoV-2 infection among inhabitants of Bamako, after the first epidemic wave. We assessed demographic, social and living conditions, health behaviours and knowledges associated with SARS-CoV-2 seropositivity. We conducted a cross-sectional multistage household survey during September 2020, in three neighbourhoods of the commune VI (Bamako), where 30% of the cases were reported. We recruited 1526 inhabitants in 3 areas, that is, 306 households, and 1327 serological results (≥1 years), 220 household questionnaires and collected answers for 962 participants (≥12 years). We measured serological status, detecting SARS-CoV-2 spike protein antibodies in blood sampled. We documented housing conditions and individual health behaviours through questionnaires among participants. We estimated the number of SARS-CoV-2 infections and deaths in the population of Bamako using the age and sex distributions. The prevalence of SARS-CoV-2 seropositivity was 16.4% (95% CI 15.1% to 19.1%) after adjusting on the population structure. This suggested that ~400 000 cases and ~2000 deaths could have occurred of which only 0.4% of cases and 5% of deaths were officially reported. Questionnaires analyses suggested strong agreement with washing hands but lower acceptability of movement restrictions (lockdown/curfew), and mask wearing. The first wave of SARS-CoV-2 spread broadly in Bamako. Expected fatalities remained limited largely due to the population age structure and the low prevalence of comorbidities. Improving diagnostic capacities to encourage testing and preventive behaviours, and avoiding the spread of false information remain key pillars, regardless of the developed or developing setting. This study was registered in the registry of the ethics committee of the Faculty of Medicine and Odonto-Stomatology and the Faculty of Pharmacy, Bamako, Mali, under the number: 2020/162/CA/FMOS/FAPH

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance.

Investment in severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing in Africa over the past year has led to a major increase in the number of sequences that have been generated and used to track the pandemic on the continent, a number that now exceeds 100,000 genomes. Our results show an increase in the number of African countries that are able to sequence domestically and highlight that local sequencing enables faster turnaround times and more-regular routine surveillance. Despite limitations of low testing proportions, findings from this genomic surveillance study underscore the heterogeneous nature of the pandemic and illuminate the distinct dispersal dynamics of variants of concern-particularly Alpha, Beta, Delta, and Omicron-on the continent. Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve while the continent faces many emerging and reemerging infectious disease threats. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

The evolving SARS-CoV-2 epidemic in Africa: Insights from rapidly expanding genomic surveillance

INTRODUCTION Investment in Africa over the past year with regard to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) sequencing has led to a massive increase in the number of sequences, which, to date, exceeds 100,000 sequences generated to track the pandemic on the continent. These sequences have profoundly affected how public health officials in Africa have navigated the COVID-19 pandemic. RATIONALE We demonstrate how the first 100,000 SARS-CoV-2 sequences from Africa have helped monitor the epidemic on the continent, how genomic surveillance expanded over the course of the pandemic, and how we adapted our sequencing methods to deal with an evolving virus. Finally, we also examine how viral lineages have spread across the continent in a phylogeographic framework to gain insights into the underlying temporal and spatial transmission dynamics for several variants of concern (VOCs). RESULTS Our results indicate that the number of countries in Africa that can sequence the virus within their own borders is growing and that this is coupled with a shorter turnaround time from the time of sampling to sequence submission. Ongoing evolution necessitated the continual updating of primer sets, and, as a result, eight primer sets were designed in tandem with viral evolution and used to ensure effective sequencing of the virus. The pandemic unfolded through multiple waves of infection that were each driven by distinct genetic lineages, with B.1-like ancestral strains associated with the first pandemic wave of infections in 2020. Successive waves on the continent were fueled by different VOCs, with Alpha and Beta cocirculating in distinct spatial patterns during the second wave and Delta and Omicron affecting the whole continent during the third and fourth waves, respectively. Phylogeographic reconstruction points toward distinct differences in viral importation and exportation patterns associated with the Alpha, Beta, Delta, and Omicron variants and subvariants, when considering both Africa versus the rest of the world and viral dissemination within the continent. Our epidemiological and phylogenetic inferences therefore underscore the heterogeneous nature of the pandemic on the continent and highlight key insights and challenges, for instance, recognizing the limitations of low testing proportions. We also highlight the early warning capacity that genomic surveillance in Africa has had for the rest of the world with the detection of new lineages and variants, the most recent being the characterization of various Omicron subvariants. CONCLUSION Sustained investment for diagnostics and genomic surveillance in Africa is needed as the virus continues to evolve. This is important not only to help combat SARS-CoV-2 on the continent but also because it can be used as a platform to help address the many emerging and reemerging infectious disease threats in Africa. In particular, capacity building for local sequencing within countries or within the continent should be prioritized because this is generally associated with shorter turnaround times, providing the most benefit to local public health authorities tasked with pandemic response and mitigation and allowing for the fastest reaction to localized outbreaks. These investments are crucial for pandemic preparedness and response and will serve the health of the continent well into the 21st century

Etude de la qualité de l’eau chlorée et des conditions d’utilisation au Centre Hospitalier Universitaire Sourou Sanou (CHUSS) de Bobo-Dioulasso

L’eau chlorée est un désinfectant efficace et facile à préparer. Le département de la pharmacie du Centre Hospitalier Universitaire Sourou Sanou (CHUSS) est chargé de la préparation de l’eau chlorée qui est utilisée dans les services de l’hôpital depuis 2003. La qualité chimique, les conditions de production et d’utilisation de cette eau chlorée demeurent inconnues alors que les normes de bonnes pratiques exigent un contrôle de qualité de la production et de l’utilisation. Le but de cette étude était de contribuer à évaluer la qualité de l'eau chlorée et les conditions d’utilisation au CHUSS.Il s’agissait d’une enquête sur les conditions de production, d’utilisation et une analyse chimique de la qualité de l’eau chlorée. L’étude s’est déroulée du 1er Juillet au 30 Septembre 2014 au CHUSS.Elle a révélé que la production de l’eau chlorée ne respectait pas les recommandations du fabricant de l’appareil de production. La concentration moyenne en chlore actif mesurée à la production (2,74 ± 0,25 g/L) était inférieure à celle attendue (5 g/L). Le pH de l’eau chlorée à la production était de 8,42 ± 0,03. Les conditions d'utilisation étaient parfois non conformes. Des travaux ultérieurs sur l’efficacité microbiologique de cette eau chlorée doivent être envisagés. Mots-clés: désinfectants, eau chlorée, productions, utilisation, CHUSS. English Title:&nbsp;Study of the quality of chlorinated water and the conditions of use at the Sourou Sanou University Hospital Center (CHUSS) in Bobo-Dioulasso. English Abstract Chlorinated water is an effective disinfectant and easy to prepare. The pharmacy department of the University Hospital Center of Sourou Sanou (CHUSS) is responsible for the preparation of chlorinated water which has been used in hospital departments since 2003. The chemical quality, the conditions of production and use of this chlorinated water remains unknown. However, good practice standards require quality control of production and use. The aim of this study was to help assess the quality of chlorinated water and the conditions of use at CHUSS. It was a survey on the conditions of production, use and a chemical analysis of the quality of chlorinated water. The study took place from July 1 to September 30, 2014 at CHUSS. The investigation revealed that the production of chlorinated water did not meet the recommendations of the manufacturer of the production device. The average concentration of active chlorine measured at production (2.74 ± 0.25 g / L) was lower than that expected (5 g / L). The production pH of chlorinated water was 8.42 ± 0.03. The conditions of use were sometimes non-compliant. Further work on the microbiological effectiveness of this chlorinated water should be considered. Keywords: disinfectants, chlorinated water, production, utilisation, CHUS

Molecular Detection of Microorganisms Associated with Small Mammals and Their Ectoparasites in Mali

International audienc

Zika Virus Circulation in Mali

International audienceThe circulation of Zika virus (ZIKV) in Mali has not been clearly characterized. Therefore, we conducted a serologic survey of 793 asymptomatic volunteers >15 years of age (2016), and 637 blood donors (2013) to assess the seroprevalence of ZIKV infection in 2 ecoclimatic regions of Mali, tropical savannah and warm semiarid region, using ELISA and seroneutralization assays. The overall seroprevalence was ≈12% and increased with age, with no statistical difference between male and female participants. In the warm semiarid study sites we detected immunological markers of an outbreak that occurred in the late 1990s in 18% (95% CI 13%-23%) of participants. In tropical savannah sites, we estimated a low rate of endemic transmission, with 2.5% (95% CI 2.0%-3.1%) of population infected by ZIKV annually. These data demonstrate the circulation of ZIKV in Mali and provide evidence of a previously unidentified outbreak that occurred in the late 1990s