#Risk of #dengue in Central #Africa: #Vector competence studies with #Aedes aegypti and Aedes albopictus (Diptera: Culicidae) populations and dengue 2 virus (PLOS Negl Trop Dis., abstract)

[Source: PLOS Neglected Tropical Diseases, full page: (LINK). Abstract, edited.]

OPEN ACCESS /  PEER-REVIEWED / RESEARCH ARTICLE

Risk of dengue in Central Africa: Vector competence studies with Aedes aegypti and Aedes albopictus (Diptera: Culicidae) populations and dengue 2 virus

Basile Kamgang , Marie Vazeille, Armel N. Tedjou, Theodel A. Wilson-Bahun, Aurélie P. Yougang, Laurence Mousson, Charles S. Wondji , Anna-Bella Failloux

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Published: December 30, 2019 / DOI: https://doi.org/10.1371/journal.pntd.0007985 / This is an uncorrected proof.

 

Abstract

Introduction

Dengue is the most important mosquito-borne diseases worldwide but was considered scarce in West-Central Africa. During the last decade, dengue outbreaks have increasingly been reported in urban foci in this region suggesting major epidemiological changes. However, in Central Africa where both vectors, Aedes aegypti and Aedes albopictus are well established, the role of each species in dengue transmission remains poorly investigated.

Methodology/Principal findings

Field-collected strains of Ae. aegypti and Ae. albopictus from different ecological settings in Central Africa were experimentally challenged with dengue 2 virus (DENV-2). Mosquitoes were analysed at 14- and 21-days post-infection. Analysis provide evidence that both Ae. aegypti and Ae. albopictus in Central Africa were able to transmit dengue virus with Ae. aegypti exhibiting a higher transmission rate. Unexpectedly, two Ae. aegypti populations from Bénoué and Maroua, in northern Cameroon, were not able to transmit DENV-2.

Conclusions/Significance

We conclude that both Ae. aegypti and Ae. albopictus are susceptible to DENV-2 and may intervene as active dengue vectors. These findings highlight the urgent need to plan a vector surveillance program and control methods against dengue vectors in Central Africa in order to prevent future outbreaks.

 

Author summary

Dengue virus (DENV) is a flavivirus mainly transmitted to humans through the bite of infected mosquitoes notably Aedes aegypti and Aedes albopictus. In Central Africa where both vectors, Ae. aegypti and Ae. albopictus are well established, the role of each species in dengue transmission remains poorly investigated. Here, we assessed the vector competence of Ae. aegypti and Ae. albopictus collected in different ecological settings in Central Africa to transmit dengue 2 virus (DENV-2). We provide evidence that both Ae. aegypti and Ae. albopictus in Central Africa were able to transmit dengue virus with Ae. aegypti exhibiting a higher transmission rate. These findings could increase the risk of dengue outbreak in the region and emphasize the need for a comprehensive vector surveillance program to prevent and preparedness for an intervention in case of outbreaks.

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Citation: Kamgang B, Vazeille M, Tedjou AN, Wilson-Bahun TA, Yougang AP, Mousson L, et al. (2019) Risk of dengue in Central Africa: Vector competence studies with Aedes aegypti and Aedes albopictus (Diptera: Culicidae) populations and dengue 2 virus. PLoS Negl Trop Dis 13(12): e0007985. https://doi.org/10.1371/journal.pntd.0007985

Editor: Duane J. Gubler, Duke-NUS GMS, SINGAPORE

Received: September 9, 2019; Accepted: December 10, 2019; Published: December 30, 2019

Copyright: © 2019 Kamgang et al. 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 credited.

Data Availability: All relevant data are within the manuscript.

Funding: BK was funded by the Wellcome Trust, 204862/Z/16/Z (https://wellcome.ac.uk). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.

Competing interests: The authors have declared that no competing interests exist.

Keywords: Flavivirus; Dengue fever; Africa region; Mosquitoes; Aedes aegypti; Aedes albopictus.

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#Enzootic #patterns of #MERS #coronavirus in imported #African and local #Arabian dromedary #camels: a prospective genomic study (Lancet Planet Health, abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Lancet Planet Health. 2019 Dec 11. pii: S2542-5196(19)30243-8. doi: 10.1016/S2542-5196(19)30243-8. [Epub ahead of print]

Enzootic patterns of Middle East respiratory syndrome coronavirus in imported African and local Arabian dromedary camels: a prospective genomic study.

El-Kafrawy SA1, Corman VM2, Tolah AM3, Al Masaudi SB4, Hassan AM5, Müller MA6, Bleicker T7, Harakeh SM1, Alzahrani AA8, Alsaaidi GA8, Alagili AN9, Hashem AM10, Zumla A11, Drosten C12, Azhar EI13.

Author information: 1 Special Infectious Agent Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia. 2 Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Berlin Institute of Health, Institute of Virology, Berlin, Germany; German Centre for Infection Research, associated partner Charité, Berlin, Germany. 3 Special Infectious Agent Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Biological Science, Division of Microbiology, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia. 4 Department of Biological Science, Division of Microbiology, Faculty of Science, King Abdulaziz University, Jeddah, Saudi Arabia. 5 Special Infectious Agent Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia. 6 Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Berlin Institute of Health, Institute of Virology, Berlin, Germany; German Centre for Infection Research, associated partner Charité, Berlin, Germany; Martsinovsky Institute of Medical Parasitology, Tropical and Vector Borne Diseases, Sechenov University, Moscow, Russia. 7 Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Berlin Institute of Health, Institute of Virology, Berlin, Germany. 8 Directorate of Agriculture, Ministry of Environment Water and Agriculture, Makkah Region, Saudi Arabia. 9 Mammals Research Chair, Department of Zoology, College of Science, King Saud University, Riyadh, Saudi Arabia. 10 Special Infectious Agent Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Microbiology and Parasitology, Faculty of Medicine, King Abdulaziz University, Jeddah, Saudi Arabia. 11 Department of Infection, Division of Infection and Immunity, Centre for Clinical Microbiology, University College London, London, UK; NIHR Biomedical Research Centre, University College London Hospitals, London, UK. 12 Charité-Universitätsmedizin Berlin, corporate member of Freie Universität Berlin, Humboldt-Universität zu Berlin, Germany; Berlin Institute of Health, Institute of Virology, Berlin, Germany; German Centre for Infection Research, associated partner Charité, Berlin, Germany. Electronic address: christian.drosten@charite.de. 13 Special Infectious Agent Unit, King Fahd Medical Research Center, King Abdulaziz University, Jeddah, Saudi Arabia; Department of Medical Laboratory Technology, Faculty of Applied Medical Sciences, King Abdulaziz University, Jeddah, Saudi Arabia. Electronic address: eazhar@kau.edu.sa.

 

Abstract

BACKGROUND:

The Middle East respiratory syndrome coronavirus (MERS-CoV) is a lethal zoonotic pathogen endemic to the Arabian Peninsula. Dromedary camels are a likely source of infection and the virus probably originated in Africa. We studied the genetic diversity, geographical structure, infection prevalence, and age-associated prevalence among camels at the largest entry port of camels from Africa into the Arabian Peninsula.

METHODS:

In this prospective genomic study, we took nasal samples from camels imported from Sudan and Djibouti into the Port of Jeddah in Jeddah, Saudi Arabia, over an almost 2-year period and local Arabian camels over 2 months in the year after surveillance of the port. We determined the prevalence of MERS-CoV infection, age-associated patterns of infection, and undertook phylogeographical and migration analyses to determine intercountry virus transmission after local lineage establishment. We compared all virological characteristics between the local and imported cohorts. We compared major gene deletions between African and Arabian strains of the virus. Reproductive numbers were inferred with Bayesian birth death skyline analyses.

FINDINGS:

Between Aug 10, 2016, and May 3, 2018, we collected samples from 1196 imported camels, of which 868 originated from Sudan and 328 from Djibouti, and between May 1, and June 25, 2018, we collected samples from 472 local camels, of which 189 were from Riyadh and 283 were from Jeddah, Saudi Arabia. Virus prevalence was higher in local camels than in imported camels (224 [47·5%] of 472 vs 157 [13·1%] of 1196; p<0·0001). Infection prevalence peaked among camels older than 1 year and aged up to 2 years in both groups, with 255 (66·9%) of 381 positive cases in this age group. Although the overall geographical distribution of the virus corresponded with the phylogenetic tree topology, some virus exchange was observed between countries corresponding with trade routes in the region. East and west African strains of the virus appear to be geographically separated, with an origin of west African strains in east Africa. African strains of the virus were not re-sampled in Saudi Arabia despite sampling approximately 1 year after importation from Africa. All local Arabian samples contained strains of the virus that belong to a novel recombinant clade (NRC) first detected in 2014 in Saudi Arabia. Reproduction number estimates informed by the sequences suggest sustained endemicity of NRC, with a mean Re of 1·16.

INTERPRETATION:

Despite frequent imports of MERS-CoV with camels from Africa, African lineages of MERS-CoV do not establish themselves in Saudi Arabia. Arabian strains of the virus should be tested for changes in virulence and transmissibility.

FUNDING:

German Ministry of Research and Education, EU Horizon 2020, and Emerging Diseases Clinical Trials Partnership.

Copyright © 2019 The Author(s). Published by Elsevier Ltd. This is an Open Access article under the CC BY 4.0 license. Published by Elsevier Ltd.. All rights reserved.

PMID: 31843456 DOI: 10.1016/S2542-5196(19)30243-8

Keywords: MERS-CoV; Camels; Africa Region; Saudi Arabia; Recombination.

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#Prevalence and outcome of #bloodstream #infections due to third-generation #cephalosporin-resistant #Enterobacteriaceae in sub-Saharan #Africa: a systematic review (J Antimicrob Chemother., abstract)

[Source: Journal of Antimicrobial Chemotherapy, full page: (LINK). Abstract, edited.]

Prevalence and outcome of bloodstream infections due to third-generation cephalosporin-resistant Enterobacteriaceae in sub-Saharan Africa: a systematic review

Rebecca Lester, Patrick Musicha, Nadja van Ginneken, Angela Dramowski, Davidson H Hamer, Paul Garner, Nicholas A Feasey

Journal of Antimicrobial Chemotherapy, dkz464, https://doi.org/10.1093/jac/dkz464

Published: 19 November 2019

 

Abstract

Background

The prevalence of bacterial bloodstream infections (BSIs) in sub-Saharan Africa (sSA) is high and antimicrobial resistance is likely to increase mortality from these infections. Third-generation cephalosporin-resistant (3GC-R) Enterobacteriaceae are of particular concern, given the widespread reliance on ceftriaxone for management of sepsis in Africa.

Objectives

Reviewing studies from sSA, we aimed to describe the prevalence of 3GC resistance in Escherichia coli, Klebsiella and Salmonella BSIs and the in-hospital mortality from 3GC-R BSIs.

Methods

We systematically reviewed studies reporting 3GC susceptibility testing of E. coli, Klebsiella and Salmonella BSI. We searched PubMed and Scopus from January 1990 to September 2019 for primary data reporting 3GC susceptibility testing of Enterobacteriaceae associated with BSI in sSA and studies reporting mortality from 3GC-R BSI. 3GC-R was defined as phenotypic resistance to ceftriaxone, cefotaxime or ceftazidime. Outcomes were reported as median prevalence of 3GC resistance for each pathogen.

Results

We identified 40 articles, including 7 reporting mortality. Median prevalence of 3GC resistance in E. coli was 18.4% (IQR 10.5 to 35.2) from 20 studies and in Klebsiella spp. was 54.4% (IQR 24.3 to 81.2) from 28 studies. Amongst non-typhoidal salmonellae, 3GC resistance was 1.9% (IQR 0 to 6.1) from 12 studies. A pooled mortality estimate was prohibited by heterogeneity.

Conclusions

Levels of 3GC resistance amongst bloodstream Enterobacteriaceae in sSA are high, yet the mortality burden is unknown. The lack of clinical outcome data from drug-resistant infections in Africa represents a major knowledge gap and future work must link laboratory surveillance to clinical data.

Keywords: Antibiotics; Drugs Resistance; Cephalosporins; Enterobacteriaceae; Bacteremia; Africa region.

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#Impacts of #environmental and #socioeconomic #factors on emergence and #epidemic potential of #Ebola in #Africa (Nat Commun., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

Nat Commun. 2019 Oct 15;10(1):4531. doi: 10.1038/s41467-019-12499-6.

Impacts of environmental and socio-economic factors on emergence and epidemic potential of Ebola in Africa.

Redding DW1, Atkinson PM2, Cunningham AA3, Lo Iacono G4, Moses LM5, Wood JLN6, Jones KE7,8.

Author information: 1 Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, Gower Street, London, WC1E 6BT, UK. d.redding@ucl.ac.uk. 2 Lancaster Environment Centre, Lancaster University, Bailrigg, Lancaster LA4 1YW, UK. 3 Institute of Zoology, Zoological Society of London, Regent’s Park, London, NW1 4RY, UK. 4 School of Veterinary Medicine, University of Surrey, Guildford, UK. 5 Department of Global Community Health and Behavioral Sciences, Tulane University, New Orleans, LA, USA. 6 Department of Veterinary Medicine, Disease Dynamics Unit, University of Cambridge, Cambridge, UK. 7 Centre for Biodiversity and Environment Research, Department of Genetics, Evolution and Environment, University College London, Gower Street, London, WC1E 6BT, UK. kate.e.jones@ucl.ac.uk. 8 Institute of Zoology, Zoological Society of London, Regent’s Park, London, NW1 4RY, UK. kate.e.jones@ucl.ac.uk.

 

Abstract

Recent outbreaks of animal-borne emerging infectious diseases have likely been precipitated by a complex interplay of changing ecological, epidemiological and socio-economic factors. Here, we develop modelling methods that capture elements of each of these factors, to predict the risk of Ebola virus disease (EVD) across time and space. Our modelling results match previously-observed outbreak patterns with high accuracy, and suggest further outbreaks could occur across most of West and Central Africa. Trends in the underlying drivers of EVD risk suggest a 1.75 to 3.2-fold increase in the endemic rate of animal-human viral spill-overs in Africa by 2070, given current modes of healthcare intervention. Future global change scenarios with higher human population growth and lower rates of socio-economic development yield a fourfold higher likelihood of epidemics occurring as a result of spill-over events. Our modelling framework can be used to target interventions designed to reduce epidemic risk for many zoonotic diseases.

PMID: 31615986 DOI: 10.1038/s41467-019-12499-6

Keywords: Ebola; Environmental disasters; Africa Region; Society.

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#Diversity of dromedary #camel #coronavirus #HKU23 in #African camels revealed multiple #recombination events among closely related #Betacoronaviruses of the subgenus #Embecovirus (J Virol., abstract)

[Source: Journal of Virology, full page: (LINK). Abstract, edited.]

Diversity of dromedary camel coronavirus HKU23 in African camels revealed multiple recombination events among closely related Betacoronaviruses of the subgenus Embecovirus.

Ray T. Y. So, Daniel K. W. Chu, Eve Miguel, Ranawaka A. P. M. Perera, Jamiu O. Oladipo, Ouafaa Fassi-Fihri, Gelagay Aylet, Ronald L. W. Ko, Ziqi Zhou, Mo-Sheung Cheng, Sulyman A. Kuranga, François L. Roger, Veronique Chevalier, Richard J. Webby, Patrick C. Y. Woo, Leo L. M. Poon, Malik Peiris

DOI: 10.1128/JVI.01236-19

 

ABSTRACT

Genetic recombination has frequently been observed in coronaviruses. Here, we sequenced multiple complete genomes of dromedary camel coronavirus HKU23 (DcCoV-HKU23) from Nigeria, Morocco and Ethiopia and identified several genomic positions indicative of cross species virus recombination events among other Betacoronaviruses of the subgenus Embecovirus (clade A β-CoVs). Recombinant fragments of a rabbit coronavirus (RbCoV-HKU14) were identified at the hemagglutinin esterase gene position. Homolog fragments of a rodent CoV were also observed at the 8.9 kDa open reading frame 4a at the 3′ end of the spike gene. The patterns of recombination varied geographically across the African region, highlighting a mosaic structure of DcCoV-HKU23 genomes circulating in dromedaries. Our results highlighted active recombination of coronaviruses circulating in dromedaries and is also relevant to the emergence and evolution of other Betacoronaviruses including MERS-coronavirus (MERS-CoV).

 

IMPORTANCE

Genetic recombination is often demonstrated in coronaviruses and can result in host range expansion or alteration in tissue tropism. Here, we showed interspecies recombination events of an endemic dromedary camel coronavirus HKU23 with other clade A Betacoronaviruses. Our results supported the possibility that the zoonotic pathogen, MERS-CoV, which also co-circulates in the same camel species, may have undergone similar recombination events facilitating its emergence or may do so in its future evolution.

Copyright © 2019 American Society for Microbiology. All Rights Reserved.

Keywords: Coronavirus; Betacoronavirus; Embecovirus; MERS-CoV; Camels; Africa Region; Recombination.

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#Aetiology of invasive #bacterial #infection and #antimicrobial #resistance in #neonates in sub-Saharan #Africa:… (Lancet Infect Dis., abstract)

[Source: The Lancet Infectious Diseases, full  page: (LINK). Abstract, edited.]

Aetiology of invasive bacterial infection and antimicrobial resistance in neonates in sub-Saharan Africa: a systematic review and meta-analysis in line with the STROBE-NI reporting guidelines

Uduak Okomo, PhD, Edem N K Akpalu, MD, Kirsty Le Doare, PhD, Anna Roca, PhD, Prof Simon Cousens, Dip Maths Stat, Alexander Jarde, PhD, Prof Mike Sharland, FRCPCH, Prof Beate Kampmann, FRCPCH †, Prof Joy E Lawn, FMedSCi †

Published: September 12, 2019 / DOI: https://doi.org/10.1016/S1473-3099(19)30414-1

 

Summary

Background

Aetiological data for neonatal infections are essential to inform policies and programme strategies, but such data are scarce from sub-Saharan Africa. We therefore completed a systematic review and meta-analysis of available data from the African continent since 1980, with a focus on regional differences in aetiology and antimicrobial resistance (AMR) in the past decade (2008–18).

Methods

We included data for microbiologically confirmed invasive bacterial infection including meningitis and AMR among neonates in sub-Saharan Africa and assessed the quality of scientific reporting according to Strengthening the Reporting of Observational Studies in Epidemiology for Newborn Infection (STROBE-NI) checklist. We calculated pooled proportions for reported bacterial isolates and AMR.

Findings

We included 151 studies comprising data from 84 534 neonates from 26 countries, almost all of which were hospital-based. Of the 82 studies published between 2008 and 2018, insufficient details were reported regarding most STROBE-NI items. Regarding culture positive bacteraemia or sepsis, Staphylococcus aureus, Klebsiella spp, and Escherichia coli accounted for 25% (95% CI 21–29), 21% (16–27), and 10% (8–10) respectively. For meningitis, the predominant identified causes were group B streptococcus 25% (16–33), Streptococcus pneumoniae 17% (9–6), and S aureus 12% (3–25). Resistance to WHO recommended β-lactams was reported in 614 (68%) of 904 cases and resistance to aminoglycosides in 317 (27%) of 1176 cases.

Interpretation

Hospital-acquired neonatal infections and AMR are a major burden in Africa. More population-based neonatal infection studies and improved routine surveillance are needed to improve clinical care, plan health systems approaches, and address AMR. Future studies should be reported according to standardised reporting guidelines, such as STROBE-NI, to aid comparability and reduce research waste.

Funding

Uduak Okomo was supported by a Medical Research Council PhD Studentship

Keywords: Antibiotics; Drugs Resistance; African Region; Pediatrics.

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#Antibiotic Use in #Food #Animals in the #World with Focus on #Africa: Pluses and Minuses (J Glob Antimicrob Resist., abstract)

[Source: US National Library of Medicine, full page: (LINK). Abstract, edited.]

J Glob Antimicrob Resist. 2019 Aug 8. pii: S2213-7165(19)30198-5. doi: 10.1016/j.jgar.2019.07.031. [Epub ahead of print]

Antibiotic Use in Food Animals in the World with Focus on Africa: Pluses and Minuses.

Van TTH1, Yidana Z2, Smooker PM3, Coloe PJ4.

Author information: 1 Biosciences & Food Technology Discipline, School of Science, RMIT University, Australia. 2 Biosciences & Food Technology Discipline, School of Science, RMIT University, Australia; Kintampo Health Research Centre, Kintampo, Ghana. 3 Biosciences & Food Technology Discipline, School of Science, RMIT University, Australia. Electronic address: peter.smooker@rmit.edu.au. 4 College of Science, Engineering and Health, RMIT University, Australia.

 

Abstract

Antibiotics are sometimes used in food animal production in developing countries to promote the well-being and growth of the animals. This practice provides some economic benefits to producers and consumers at large. Nevertheless, this practice is associated with a number of concerns. A major concern has been that repeatedly exposing these animals to small doses of antibiotics contributes significantly to antibiotic resistance, since a good fraction of the antibiotics used are the same or surrogates of antibiotics used in human therapeutic practices. Studies over decades have shown an explicit relationship between antimicrobial use and antimicrobial resistance in veterinary science. Many antibiotics can be purchased over the counter in African countries and antibiotic resistance is an important issue to address in this region. This review examines some of the risks and benefits associated with antibiotic use in food animals. We conclude that the use of antibiotics in food animal production constitutes a major contributing factor to the current antibiotic resistance crisis and they should only be used for treatment of sick animals based on prior diagnosis of disease.

Copyright © 2019. Published by Elsevier Ltd.

KEYWORDS: Africa; Antibiotic; Antibiotic resistance; Bacteria; Food animals; Growth promoters

PMID: 31401170 DOI: 10.1016/j.jgar.2019.07.031

Keywords: Antibiotics; Drugs Resistance; Poultry; Cattle; Food Safety; Africa.

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