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1.
BMC Infect Dis ; 21(1): 1090, 2021 Oct 23.
Article in English | MEDLINE | ID: mdl-34688270

ABSTRACT

BACKGROUND: Bacterial vaginosis (BV) is associated with a higher risk of preterm delivery and spontaneous abortion. Yet little data on BV prevalence exist for sub-Saharan countries. The aim of this study was to estimate the prevalence of bacterial vaginosis and associated risk factors among pregnant women in Senegal. METHODS: From October 2013 to December 2018, pregnant women in their third trimester were recruited in two primary health centers (one suburban, one rural) in Senegal. Healthcare workers interviewed women and collected a lower vaginal swab and a blood sample. Vaginal flora were classified into four categories using vaginal smear microscopic examination and Gram's coloration. In our study, BV was defined as vaginal flora with no Lactobacillus spp. Variables associated with BV were analyzed using STATA® through univariate and multivariate analysis. RESULTS: A total of 457 women provided a vaginal sample for analysis. Overall, BV prevalence was 18.6% (85/457) [95% CI 15.4-22.6]) and was similar in suburban and rural areas (18.9% versus 18.1%, p = 0.843). Multivariate analysis showed that primigravidity was the only factor independently associated with a lower risk of BV (aOR 0.35 [95% CI 0.17-0.72]). CONCLUSIONS: Our study showed significant BV prevalence among pregnant women in Senegal. Although the literature has underscored the potential consequences of BV for obstetric outcomes, data are scarce on BV prevalence in sub-Saharan African countries. Before authorities consider systematic BV screening for pregnant women, a larger study would be useful in documenting prevalence, risk factors and the impact of BV on pregnancy outcomes.


Subject(s)
Pregnancy Complications, Infectious , Vaginosis, Bacterial , Female , Humans , Infant, Newborn , Pregnancy , Pregnancy Complications, Infectious/epidemiology , Pregnant Women , Risk Factors , Senegal/epidemiology , Vagina , Vaginosis, Bacterial/epidemiology
2.
Am J Trop Med Hyg ; 105(5): 1339-1346, 2021 08 30.
Article in English | MEDLINE | ID: mdl-34460418

ABSTRACT

Maternal group B Streptococcus (GBS) colonization is a major risk factor for neonatal GBS infection. However, data on GBS are scarce in low- and middle-income countries. Using sociodemographic data and vaginal swabs collected from an international cohort of mothers and newborns, this study aimed to estimate the prevalence of GBS colonization among pregnant women in Madagascar (n = 1,603) and Senegal (n = 616). The prevalence was 5.0% (95% CI, 3.9-6.1) and 16.1% (95% CI, 13.1-19.0) in Madagascar and Senegal, respectively. No factors among sociodemographic characteristics, living conditions, and obstetric history were found to be associated independently with GBS colonization in both countries. This community-based study provides one of the first estimates of maternal GBS colonization among pregnant women from Madagascar and Senegal.


Subject(s)
Maternal Exposure/statistics & numerical data , Mothers/statistics & numerical data , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Streptococcal Infections/diagnosis , Streptococcal Infections/epidemiology , Streptococcus/isolation & purification , Adult , Cohort Studies , Female , Humans , Infant, Newborn , Madagascar/epidemiology , Population Surveillance , Pregnancy , Pregnant Women , Prevalence , Senegal/epidemiology
3.
Clin Microbiol Infect ; 27(12): 1858.e9-1858.e15, 2021 Dec.
Article in English | MEDLINE | ID: mdl-33838304

ABSTRACT

OBJECTIVE: A massive scale-up of testing and treatment is indicated to globally eliminate hepatitis B virus (HBV) infection. However, access to a polymerase chain reaction (PCR), a key test to quantify HBV DNA levels and determine treatment eligibility, is limited in resource-limited countries. We have developed and evaluated the loop-mediated isothermal amplification (LAMP) assay to diagnose clinically important HBV DNA thresholds defined by the WHO (≥20 000 and ≥ 200 000 IU/mL). METHODS: Pan-genotypic primer sets were designed on conserved HBV gene regions. Accuracy of LAMP to identify highly viraemic patients was evaluated in 400 and 550 HBV-infected people in France and Senegal, respectively. RESULTS: Our primers successfully detected eight major HBV genotypes/sub-genotypes (A1/2/3/B/C/D/E/F) with a detection limit ranging between 40 and 400 IU/mL. In France, the area under the receiver operating characteristic curve (AUROC), sensitivity and specificity of bead-based extraction and real-time turbidimetric LAMP were 0.95 (95% CI 0.93-0.97), 91.1% and 86.0%, respectively, to diagnose HBV DNA ≥20 000 IU/mL; and 0.98 (0.97-0.99), 98.0% and 94.6% for ≥200 000 IU/mL. The performance did not vary by viral genotypes. In Senegal, using a field-adapted method (reagent-free boil-and-spin extraction and inexpensive end-point fluorescence detection), the AUROC, sensitivity and specificity were 0.95 (0.93-0.97), 98.7% and 91.5%, respectively, to diagnose HBV DNA ≥200 000 IU/mL. The assay was not adapted to discriminate low-level viraemia. DISCUSSION: We have developed a simple, rapid (60 min), and inexpensive (US$8/assay) alternative to PCR to diagnose high viraemia ≥200 000 IU/mL. HBV-LAMP may contribute to eliminating HBV mother-to-child transmission by identifying high-risk pregnant women eligible for antiviral prophylaxis in resource-limited countries.


Subject(s)
DNA, Viral , Hepatitis B , Nucleic Acid Amplification Techniques , DNA, Viral/isolation & purification , Female , France , Hepatitis B/diagnosis , Hepatitis B virus/genetics , Humans , Infectious Disease Transmission, Vertical , Molecular Diagnostic Techniques , Pregnancy , Senegal , Sensitivity and Specificity , Viremia
4.
Int J Antimicrob Agents ; 56(6): 106190, 2020 Dec.
Article in English | MEDLINE | ID: mdl-33045351

ABSTRACT

Due to resistance to chloroquine and sulfadoxine/pyrimethamine, treatment for uncomplicated Plasmodium falciparum malaria switched to artemisinin-based combination therapy (ACT) in 2006 in Senegal. Several mutations in the gene encoding the kelch13 helix (pfk13-propeller) have been identified as associated with in vitro and in vivo artemisinin resistance in Southeast Asia. Additionally, three mutations in the pfcoronin gene (G50E, R100K and E107V) have been identified in two culture-adapted Senegalese field isolates that became resistant in vitro to artemisinin after 4 years of intermittent selection with dihydroartemisinin. The aims of this study were to assess the prevalence of pfcoronin and pfk13 mutations in Senegalese field isolates from Dakar and to investigate their association with artemisinin derivative clinical failures. A total of 348 samples of P. falciparum from 327 patients, collected from 2015-2019 in Dakar, were successfully analysed. All sequences had wild-type pfk13 allele. The three mutations (G50E, R100K and E107V), previously identified in parasites with reduced susceptibility to artemisinin, were not found in this study, but a new mutation (P76S) was detected (mean prevalence 16.2%). The P76S mutation was identified in 5 (31.3%) of 16 isolates collected from patients still parasitaemic on Day 3 after ACT treatment and in 31 samples (15.3%) among 203 patients considered successfully cured. There was no significant association between in vivo reduced efficacy to artemisinin derivatives and the P76S mutation (P = 0.151, Fisher's exact test). These data suggest that polymorphisms in pfk13 and pfcoronin are not the best predictive markers for artemisinin resistance in Senegal.


Subject(s)
Antimalarials/therapeutic use , Artemisinins/therapeutic use , Drug Resistance/genetics , Malaria, Falciparum/drug therapy , Plasmodium falciparum/drug effects , Plasmodium falciparum/genetics , Adaptor Proteins, Signal Transducing/genetics , Doxycycline/therapeutic use , Drug Therapy, Combination , Humans , Lumefantrine/therapeutic use , Microfilament Proteins/genetics , Plasmodium falciparum/isolation & purification , Polymorphism, Single Nucleotide/genetics , Protozoan Proteins/genetics , Senegal
5.
Gut Microbes ; 11(5): 1287-1299, 2020 09 02.
Article in English | MEDLINE | ID: mdl-32404021

ABSTRACT

Background Klebsiella pneumoniae (hereafter, Kp) is a major public health threat responsible for high levels of multidrug resistant (MDR) human infections. Besides, Kp also causes severe infections in the community, especially in Asia and Africa. Although most Kp infections are caused by endogenous intestinal carriage, little is known about the prevalence and microbiological characteristics of Kp in asymptomatic human carriage, and attached risk factors including environmental sources exposure. Methods Here, 911 pregnant women from communities in Madagascar, Cambodia, and Senegal were screened for gut colonization by Kp. Characteristics of Kp strains (antimicrobial susceptibility, genomic diversity, virulence, and resistance genes) were defined, and associated risk factors were investigated. Results Kp carriage rate was 55.9%, and Kp populations were highly heterogeneous (6 phylogroups, 325 sequence types, Simpson index 99.6%). One third of Kp isolates had acquired antimicrobial resistance genes. MDR-Kp (11.7% to 39.7%) and extended spectrum beta-lactamase (ESBL)-producing Kp (0.7% to 14.7%) varied among countries. Isolates with virulence genes were detected (14.5%). Environmental exposure factors including food, animal contacts, or hospitalization of household members were associated with carriage of Kp, antimicrobial resistance and hypervirulence. However, risk factors were country-specific and Kp subpopulation-specific. Conclusion This large-scale multicenter study uncovers the huge diversity of Kp in human gut carriage, demonstrates that antimicrobial resistance is widespread in communities of three low-income countries, and underlines the challenges posed by Kp colonization to the control of antimicrobial resistance.


Subject(s)
Carrier State/epidemiology , Klebsiella Infections/epidemiology , Klebsiella pneumoniae/isolation & purification , Pregnancy Complications, Infectious/epidemiology , Adult , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/therapeutic use , Cambodia/epidemiology , Cross-Sectional Studies , Diet , Drug Resistance, Bacterial/genetics , Drug Resistance, Multiple, Bacterial/genetics , Feces/microbiology , Female , Genes, Bacterial , Hand Disinfection , Humans , Infant, Newborn , Klebsiella Infections/microbiology , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/genetics , Klebsiella pneumoniae/pathogenicity , Madagascar/epidemiology , Phylogeny , Plasmids , Pregnancy , Pregnancy Complications, Infectious/microbiology , Risk Factors , Rural Health , Senegal/epidemiology , Urban Health , Virulence
6.
Malar J ; 18(1): 293, 2019 Aug 28.
Article in English | MEDLINE | ID: mdl-31455301

ABSTRACT

BACKGROUND: Resistance to all available anti-malarial drugs has emerged and spread including artemisinin derivatives and their partner drugs. Several genes involved in artemisinin and partner drugs resistance, such as pfcrt, pfmdr1, pfK13 or pfpm2, have been identified. However, these genes do not properly explain anti-malarial drug resistance, and more particularly clinical failures observed in Africa. Mutations in genes encoding for Plasmodium falciparum proteins, such as P. falciparum Acetyl-CoA transporter (PfACT), P. falciparum UDP-galactose transporter (PfUGT) and P. falciparum cyclic amine resistance locus (PfCARL) have recently been associated to resistance to imidazolopiperazines and other unrelated drugs. METHODS: Mutations on pfugt, pfact and pfcarl were characterized on 86 isolates collected in Dakar, Senegal and 173 samples collected from patients hospitalized in France after a travel in African countries from 2015 and 2016 to assess their potential association with ex vivo susceptibility to chloroquine, quinine, lumefantrine, monodesethylamodiaquine, mefloquine, dihydroartemisinin, artesunate, doxycycline, pyronaridine and piperaquine. RESULTS: No mutations were found on the genes pfugt and pfact. None of the pfcarl described mutations were identified in these samples from Africa. The K784N mutation was found in one sample and the K734M mutation was identified on 7.9% of all samples for pfcarl. The only significant differences in ex vivo susceptibility according to the K734M mutation were observed for pyronaridine for African isolates from imported malaria and for doxycycline for Senegalese parasites. CONCLUSION: No evidence was found of involvement of these genes in reduced susceptibility to standard anti-malarial drugs in African P. falciparum isolates.


Subject(s)
Antimalarials/pharmacology , Drug Resistance , Plasmodium falciparum/genetics , Polymorphism, Genetic , Protozoan Proteins/genetics , France , Senegal
7.
Acta Trop ; 196: 126-134, 2019 Aug.
Article in English | MEDLINE | ID: mdl-31108084

ABSTRACT

The emergence of resistance to artemisinin-based combination therapies (ACT) was described in Southeast Asia. In this context, the identification of molecular markers of ACT resistance partner drugs is urgently needed for monitoring the emergence and spread of resistance. Polymorphisms in transporter genes, especially of the ATP-binding cassette (ABC) superfamily, have been involved in anti-malarial drug resistance. In this study, the association between the mutations in the P. falciparum multidrug resistance 1 gene (pfmdr1, N86Y, Y184 F, S1034C, N1042D and D1246Y) or repetitive amino acid motifs in pfmdr5 and the ex vivo susceptibility to anti-malarial drugs was evaluated. Susceptibility to chloroquine, quinine, monodesethylamodiaquine, lumefantrine, piperaquine, pyronaridine, mefloquine and dihydroartemisinin was assessed in 67 Senegalese isolates. The shorter DNNN motif ranged from to 2 to 11 copy repeats, and the longer DHHNDHNNDNNN motif ranged from 0 to 2 in pfmdr5. The present study showed the association between repetitive amino acid motifs (DNNN-DHHNDDHNNDNNN) in pfmdr5 and in vitro susceptibility to 4-aminoquinoline-based antimalarial drugs. The parasites with 8 and more copy repeats of DNNN in pfmdr5 were significantly more susceptible to piperaquine. There was a significant association between parasites whose DHHNDHNNDNNN motif was absent and replaced by DHHNDNNN, DHHNDHNNDHNNDNNN or DHHNDHNNDHNNDHNNDNNN and increased susceptibility to chloroquine, monodesethylamodiaquine and pyronaridine. A significant association between both the wild-type allele N86 in pfmdr1 and the N86-184 F haplotype and reduced susceptibility to lumefantrine was confirmed. Further studies with a large number of samples are required to validate the association between these pfmdr5 alleles and the modulation of 4-aminoquinoline-based antimalarial drug susceptibility.


Subject(s)
Antimalarials/pharmacology , Drug Resistance/genetics , Multidrug Resistance-Associated Proteins/genetics , Plasmodium falciparum/drug effects , Polymorphism, Genetic , Protozoan Proteins/metabolism , ATP-Binding Cassette Transporters/metabolism , Haplotypes , Humans , Malaria, Falciparum/parasitology , Membrane Transport Proteins/genetics , Plasmodium falciparum/genetics , Protozoan Proteins/genetics
8.
Emerg Infect Dis ; 25(3): 600-601, 2019 03.
Article in English | MEDLINE | ID: mdl-30789331

ABSTRACT

Buruli ulcer is a necrotizing skin disease caused by Mycobacterium ulcerans and is usually associated with tropical climates and exposure to slow-moving or stagnant water. We report a case of Buruli ulcer that may have originated in an urban semiarid area of Senegal.


Subject(s)
Buruli Ulcer/diagnosis , Buruli Ulcer/microbiology , Mycobacterium ulcerans , Adolescent , Antitubercular Agents/pharmacology , Antitubercular Agents/therapeutic use , Buruli Ulcer/drug therapy , Buruli Ulcer/epidemiology , History, 21st Century , Humans , Male , Mycobacterium ulcerans/drug effects , Mycobacterium ulcerans/genetics , Polymerase Chain Reaction , Senegal/epidemiology
9.
Article in English | MEDLINE | ID: mdl-30782997

ABSTRACT

Dihydroartemisinin-piperaquine, which was registered in 2017 in Senegal, is not currently used as the first-line treatment against uncomplicated malaria. A total of 6.6% to 17.1% of P. falciparum isolates collected in Dakar in 2013 to 2015 showed ex vivo-reduced susceptibility to piperaquine. Neither the exonuclease E415G mutation nor the copy number variation of the plasmepsin II gene (Pfpm2), associated with piperaquine resistance in Cambodia, was detected in Senegalese parasites.


Subject(s)
Artemisinins/therapeutic use , Aspartic Acid Endopeptidases/therapeutic use , Plasmodium falciparum/drug effects , Protozoan Proteins/therapeutic use , Quinolines/therapeutic use , Animals , Antimalarials/therapeutic use , DNA Copy Number Variations , Humans , Malaria, Falciparum/drug therapy , Senegal , Treatment Failure
10.
Foodborne Pathog Dis ; 16(2): 130-136, 2019 02.
Article in English | MEDLINE | ID: mdl-30707626

ABSTRACT

The incidence of the Salmonella contamination of poultry products in Senegal is unknown. Salmonella contamination and antimicrobial drug resistance profiles in chicken carcasses were investigated. Between July 2012 and July 2013, three types of chicken carcasses (broilers, laying hens, and premises chickens) obtained from retailers in the markets of Dakar and its suburbs were tested for Salmonella contamination. Salmonella strains were isolated from 300 chicken carcasses according to International Organization for Standardization ISO 6579 (2002) guidelines. In these samples, 273 isolates were obtained, belonging to 22 serovars, and 53% samples were contaminated with at least 1 serovar. Standardized techniques were used for the susceptibility testing and serotyping of isolates. Hygiene conditions, in terms of the cleanliness of stalls, the packing of chicken carcasses in bags, and the maintenance of the cold chain at the stall, were moderately poor. The three serovars most frequently identified were Salmonella Istanbul (28%), Salmonella Brancaster (19%), and Salmonella Kentucky (13%). Overall, 21% of isolates were resistant to quinolones and fluoroquinolones. Serovar Istanbul was resistant to tetracycline (TE) and trimethoprim + sulfamethoxazole (SXT). Serovars Brancaster and Kentucky were resistant to betalactams and to quinolones or fluoroquinolones. The uncommon serovar Senftenberg had the strongest resistance profile, displaying resistance to betalactams including imipenem (IMP). Large numbers of isolates were resistant to TE (66%) and SXT (47%). Resistance to cephalosporins (5%), chloramphenicol (2%), gentamicin (8%), and IMP (1%) was less frequent. A large proportion of the broilers sold in Dakar markets were contaminated with Salmonella. This situation probably resulted from poor hygiene conditions in chicken farms and slaughterhouses and from breaks in the cold chain at some point in the distribution of poultry products.


Subject(s)
Drug Resistance, Microbial , Poultry Products/microbiology , Salmonella/drug effects , Salmonella/isolation & purification , Animals , Chickens/microbiology , Farms/standards , Female , Food Industry/standards , Salmonella/classification , Senegal , Serotyping
11.
Am J Trop Med Hyg ; 99(2): 428-434, 2018 08.
Article in English | MEDLINE | ID: mdl-29869595

ABSTRACT

Limited access to nucleic acid tests for hepatitis B virus (HBV) DNA is a significant barrier to the effective management of chronic HBV infection in resource-poor countries. Alternatively, HBV e antigen (HBeAg) may accurately indicate high viral replication. We assessed the diagnostic performance of three commercially available rapid diagnostic tests (RDTs) for HBeAg (SD Bioline, Insight and OneStep) against a quantitative chemiluminescent immunoassay (CLIA, Architect). Using stored sera from adults with chronic HBV infection, we tested RDTs in three groups in Senegal (48 HBeAg-positive, 196 HBeAg-negative, and 117 cases with high HBV DNA (≥ 106 IU/mL)) and one group in France (17 HBeAg-positive East Asians). In Senegal, the sensitivity and specificity for HBeAg detection were 29.8% and 100% for SD Bioline, 31.1% and 100% for Insight, and 42.5% and 98.4% for OneStep, respectively. The lower limits of detection of these RDTs were very high (> 2.5 log10 Paul Ehrlich Institut units/mL). Their low sensitivity was also confirmed in HBeAg-positive Asian samples (35.3-52.9%). The prevalence of HBeAg in highly viremic (≥ 106 IU/mL) Senegalese patients was low: 58.1% using CLIA and 24.5-37.5% using RDTs. Hepatitis B e antigen prevalence was similarly low in a subgroup of 28 Senegalese women of childbearing age with a high viral load (≥ 106 IU/mL). Approximately, half of highly viremic adults do not carry HBeAg in Africa, and HBeAg RDTs had remarkably poor analytical and diagnostic sensitivity. This implies that HBeAg-based antenatal screening, particularly if using the currently available HBeAg RDTs, may overlook most pregnant women at high risk of mother-to-child transmission in Africa.


Subject(s)
Hepatitis B e Antigens/blood , Hepatitis B/epidemiology , Reagent Kits, Diagnostic/standards , Adult , Case-Control Studies , DNA, Viral/isolation & purification , Female , Hepatitis B/diagnosis , Hepatitis B virus/isolation & purification , Hepatitis B, Chronic/diagnosis , Hepatitis B, Chronic/epidemiology , Humans , Immunoassay , Infectious Disease Transmission, Vertical/prevention & control , Limit of Detection , Male , Middle Aged , Pregnancy , Pregnancy Complications, Infectious/diagnosis , Pregnancy Complications, Infectious/epidemiology , Pregnancy Complications, Infectious/virology , Prevalence , Senegal , Sensitivity and Specificity , Viral Load/methods , Virus Replication , Young Adult
12.
Science ; 358(6364): 785-789, 2017 11 10.
Article in English | MEDLINE | ID: mdl-29123067

ABSTRACT

The seventh cholera pandemic has heavily affected Africa, although the origin and continental spread of the disease remain undefined. We used genomic data from 1070 Vibrio cholerae O1 isolates, across 45 African countries and over a 49-year period, to show that past epidemics were attributable to a single expanded lineage. This lineage was introduced at least 11 times since 1970, into two main regions, West Africa and East/Southern Africa, causing epidemics that lasted up to 28 years. The last five introductions into Africa, all from Asia, involved multidrug-resistant sublineages that replaced antibiotic-susceptible sublineages after 2000. This phylogenetic framework describes the periodicity of lineage introduction and the stable routes of cholera spread, which should inform the rational design of control measures for cholera in Africa.


Subject(s)
Cholera/epidemiology , Cholera/microbiology , Pandemics , Vibrio cholerae O1/classification , Vibrio cholerae O1/genetics , Africa, Eastern/epidemiology , Africa, Southern/epidemiology , Africa, Western/epidemiology , Asia/epidemiology , Genome, Bacterial , Genomics , Humans , Phylogeny , Vibrio cholerae O1/isolation & purification
13.
Int J Antimicrob Agents ; 50(2): 155-158, 2017 Aug.
Article in English | MEDLINE | ID: mdl-28689867

ABSTRACT

Resistance to most antimalarial drugs has spread from Southeast Asia to Africa. Accordingly, new therapies to use with artemisinin-based combination therapy (triple ACT) are urgently needed. Proveblue, a methylene blue preparation, was found to exhibit antimalarial activity against Plasmodium falciparum strains in vitro. Proveblue has synergistic effects when used in combination with dihydroartemisinin, and has been shown to significantly reduce or prevent cerebral malaria in mice. The objectives of the current study were to evaluate the in vitro baseline susceptibility of clinical field isolates to Proveblue, compare its activity with that of other standard antimalarial drugs and define the patterns of cross-susceptibility between Proveblue and conventional antimalarial drugs. The Proveblue IC50 of 76 P. falciparum isolates ranged from 0.5 nM to 135.1 nM, with a mean of 8.1 nM [95% confidence interval, 6.4-10.3]. Proveblue was found to be more active against P. falciparum parasites than chloroquine, quinine, monodesethylamodiaquine, mefloquine, piperaquine, doxycycline (P <0.001) and lumefantrine (P = 0.014). Proveblue was as active as pyronaridine (P = 0.927), but was less active than dihydroartemisinin and artesunate (P <0.001). The only significant cross-susceptibilities found were between Proveblue and dihydroartemisinin (r2 = 0.195, P = 0.0001), artesunate (r2 = 0.187, P = 0.0002) and piperaquine (r2 = 0.063, P = 0.029). The present study clearly demonstrates the potential of Proveblue as an effective therapeutic agent against P. falciparum. In this context, the use of Proveblue as part of the triple ACT treatment for multidrug-resistant malaria warrants further investigation.


Subject(s)
Antimalarials/pharmacology , Enzyme Inhibitors/pharmacology , Methylene Blue/pharmacology , Plasmodium falciparum/drug effects , Humans , Inhibitory Concentration 50 , Malaria, Falciparum/parasitology , Parasitic Sensitivity Tests , Plasmodium falciparum/isolation & purification , Senegal
14.
Int J Antimicrob Agents ; 49(6): 754-756, 2017 Jun.
Article in English | MEDLINE | ID: mdl-28450175

ABSTRACT

In 2006, the Senegalese National Malaria Control Programme recommended artemisinin-based combination therapy as first-line treatment for uncomplicated malaria. In addition, intravenous (i.v.) injection of artesunate and artemether has gradually replaced quinine for the treatment of severe malaria. Mutations in the propeller domain of the Kelch 13 gene (K13-propeller, PF3D71343700), such as Y493H, R539T, I543T and C580Y, were recently associated with in vivo and in vitro resistance to artemisinin in Southeast Asia. However, these mutations were not identified in Africa. In total, 181 isolates of Plasmodium falciparum from 161 patients from Dakar, Senegal, were collected between August 2015 and January 2016. The K13-propeller gene of the isolates was sequenced. A search for non-synonymous mutations in the propeller region of K13 was performed in the 181 isolates collected from Dakar from 2015 to 2016. Three synonymous mutations were detected (D464D, C469C and R471R). Of 119 patients treated with i.v. artesunate or intramuscular artemether followed by artemether/lumefantrine, 9 patients were still parasitaemic on Day 3. Parasites from these nine patients were wild-type for K13-propeller. None of the polymorphisms known to be involved in artemisinin resistance in Asia were detected. These results suggest that K13 is not the best predictive marker for artemisinin resistance in Africa. More isolates from clinical failure cases or patients with delayed parasite clearance after treatment with artemisinin derivatives are necessary to identify new molecular markers.


Subject(s)
Antimalarials/therapeutic use , Artemisinins/therapeutic use , Malaria, Falciparum/drug therapy , Malaria, Falciparum/parasitology , Plasmodium falciparum/drug effects , Polymorphism, Genetic , Protozoan Proteins/genetics , Animals , Humans , Mutation, Missense , Plasmodium falciparum/genetics , Plasmodium falciparum/isolation & purification , Point Mutation , Senegal , Sequence Analysis, DNA , Time Factors , Treatment Outcome
15.
Malar J ; 16(1): 118, 2017 03 16.
Article in English | MEDLINE | ID: mdl-28302108

ABSTRACT

BACKGROUND: In response to increasing resistance to anti-malarial drugs, Senegal adopted artemisinin-based combination therapy (ACT) as the first-line treatment for uncomplicated malaria in 2006. However, resistance of Plasmodium falciparum parasites to artemisinin derivatives, characterized by delayed parasite clearance after treatment with ACT or artesunate monotherapy, has recently emerged and rapidly spread in Southeast Asia. After 10 years of stability with rates ranging from 5.6 to 11.8%, the prevalence of parasites with reduced susceptibility in vitro to monodesethylamodiaquine, the active metabolite of an ACT partner drug, increased to 30.6% in 2014 in Dakar. Additionally, after a decrease of the in vitro chloroquine resistance in Dakar in 2009-2011, the prevalence of parasites that showed in vitro chloroquine resistance increased again to approximately 50% in Dakar since 2013. The aim of this study was to follow the evolution of the susceptibility to ACT partners and other anti-malarial drugs in 2015 in Dakar. An in vitro test is the only method currently available to provide an early indication of resistance to ACT partners. RESULTS: Thirty-two P. falciparum isolates collected in 2015 in Dakar were analysed using a standard ex vivo assay based on an HRP2 ELISA. The prevalence of P. falciparum parasites with reduced susceptibility in vitro to monodesethylamodiaquine, chloroquine, mefloquine, doxycycline and quinine was 28.1, 46.9, 45.2, 31.2 and 9.7%, respectively. None of the parasites were resistant to lumefantrine, piperaquine, pyronaridine, dihydroartemisinin and artesunate. These results confirm an increase in the reduced susceptibility to monodesethylamodiaquine observed in 2014 in Dakar and the chloroquine resistance observed in 2013. The in vitro resistance seems to be established in Dakar. Additionally, the prevalence of parasites with reduced susceptibility to doxycycline has increased two-fold compared to 2014. CONCLUSIONS: The establishment of a reduced susceptibility to monodesethylamodiaquine as well as chloroquine resistance, and the emergence of a reduced susceptibility to doxycycline are disturbing. The in vitro and in vivo surveillance of anti-malarial drugs must be implemented in Senegal.


Subject(s)
Amodiaquine/analogs & derivatives , Antimalarials/pharmacology , Chloroquine/pharmacology , Drug Resistance , Plasmodium falciparum/drug effects , Amodiaquine/pharmacology , Artemisinins/pharmacology , Drug Therapy, Combination , Senegal
16.
BMC Infect Dis ; 16(1): 587, 2016 Oct 20.
Article in English | MEDLINE | ID: mdl-27765017

ABSTRACT

BACKGROUND: Neonatal infection constitutes one of Senegal's most important public health problems, with a mortality rate of 41 deaths per 1,000 live births. METHODS: Between January 2007 and March 2008, 242 neonates with suspected infection were recruited at three neonatal intensive care units in three major tertiary care centers in Dakar, the capital of Senegal. Neonatal infections were confirmed by positive bacterial blood or cerebrospinal fluid culture. The microbiological pattern of neonatal infections and the antibiotic susceptibility of the isolates were characterized. In addition, the genetic basis for antibiotic resistance and the genetic background of third-generation cephalosporin-resistant (3GC-R) Enterobacteriaceae were studied. RESULTS: A bacteriological infection was confirmed in 36.4 % (88/242) of neonates: 22.7 % (30/132) during the early-onset and 52.7 % (58/110) during the late-onset periods (p > 0.20). Group B streptococci accounted for 6.8 % of the 88 collected bacterial isolates, while most of them were Enterobacteriaceae (n = 69, 78.4 %). Of these, 55/69 (79.7 %) were 3GC-R. The bla CTX-M-15 allele, the bla SHV and the bla TEM were highly prevalent (63.5, 65.4 and 53.8 %, respectively), usually associated with qnr genes (65.4 %). Clonally related strains of 3GC-R Klebsiella pneumoniae and 3GC-R Enterobacter cloacae, the two most commonly recovered 3GC-R Enterobacteriaceae (48/55), were detected at the three hospitals, underlining the role of cross-transmission in their spread. The overall case fatality rate was 18.6 %. CONCLUSIONS: Measures should be taken to prevent nosocomial infections and the selection of resistant bacteria.


Subject(s)
Cephalosporins/pharmacology , Enterobacteriaceae Infections/microbiology , Enterobacteriaceae/drug effects , beta-Lactam Resistance/drug effects , Enterobacter cloacae/drug effects , Enterobacter cloacae/isolation & purification , Enterobacter cloacae/pathogenicity , Enterobacteriaceae/isolation & purification , Enterobacteriaceae/pathogenicity , Enterobacteriaceae Infections/drug therapy , Enterobacteriaceae Infections/epidemiology , Female , Humans , Infant, Newborn , Klebsiella pneumoniae/drug effects , Klebsiella pneumoniae/isolation & purification , Klebsiella pneumoniae/pathogenicity , Male , Microbial Sensitivity Tests , Senegal/epidemiology , Tertiary Care Centers , Treatment Outcome , beta-Lactam Resistance/genetics , beta-Lactamases/genetics
18.
Nat Microbiol ; 1: 16027, 2016 03 21.
Article in English | MEDLINE | ID: mdl-27572446

ABSTRACT

Together with plague, smallpox and typhus, epidemics of dysentery have been a major scourge of human populations for centuries(1). A previous genomic study concluded that Shigella dysenteriae type 1 (Sd1), the epidemic dysentery bacillus, emerged and spread worldwide after the First World War, with no clear pattern of transmission(2). This is not consistent with the massive cyclic dysentery epidemics reported in Europe during the eighteenth and nineteenth centuries(1,3,4) and the first isolation of Sd1 in Japan in 1897(5). Here, we report a whole-genome analysis of 331 Sd1 isolates from around the world, collected between 1915 and 2011, providing us with unprecedented insight into the historical spread of this pathogen. We show here that Sd1 has existed since at least the eighteenth century and that it swept the globe at the end of the nineteenth century, diversifying into distinct lineages associated with the First World War, Second World War and various conflicts or natural disasters across Africa, Asia and Central America. We also provide a unique historical perspective on the evolution of antibiotic resistance over a 100-year period, beginning decades before the antibiotic era, and identify a prevalent multiple antibiotic-resistant lineage in South Asia that was transmitted in several waves to Africa, where it caused severe outbreaks of disease.


Subject(s)
Dysentery, Bacillary/epidemiology , Dysentery, Bacillary/microbiology , Evolution, Molecular , Phylogeography , Serogroup , Shigella dysenteriae/classification , Shigella dysenteriae/isolation & purification , Drug Resistance, Bacterial , Dysentery, Bacillary/history , Genome, Bacterial , Global Health , History, 19th Century , History, 20th Century , History, 21st Century , Humans , Molecular Epidemiology , Sequence Analysis, DNA , Shigella dysenteriae/genetics
19.
PLoS One ; 11(6): e0157683, 2016.
Article in English | MEDLINE | ID: mdl-27355480

ABSTRACT

Nosocomial infections are very common in African hospitals, particularly in neonatal units. These infections are most often caused by bacteria such as Escherichia coli, Klebsiella spp and Staphylococcus spp. Salmonella strains are rarely involved in nosocomial infections. Here, we report the first description of S. Grumpensis in neonatal infections in Senegal. Seventeen Salmonella strains were isolated from hospitalized infants' stool samples. The following resistance phenotype was described in strains: AMXRTICRCFR FOXRCFXRCTXRCAZRIMPSATMRNARNORRCIPRTMRGMRTERSXTR. All isolates were susceptible to imipenem, 15 out of 17 produced an extended spectrum ß-lactamase (ESBL). blaOXA-1, blaSHV-1, blaTEM-1, blaCTX-M1 genes were detected in strains 8, 13, 5 and 8, respectively. blaCTX-M1 sequencing revealed the presence of blaCTX-M-109. Thirteen of the 17 Salmonella Grumpensis strains were analyzed by PFGE. These 13 isolates belonged to a single pulsotype and were genotypically identical. This is the first report of neonatal S. Grumpensis infections in Senegal, and the first report of blaCTX-M-109 in the genus Salmonella.


Subject(s)
Bacterial Proteins/genetics , Salmonella Infections/microbiology , Salmonella/genetics , beta-Lactamases/genetics , Anti-Bacterial Agents/pharmacology , Bacterial Typing Techniques , Cross Infection/microbiology , Drug Resistance, Bacterial , Electrophoresis, Gel, Pulsed-Field , Genotype , Humans , Infant , Infant, Newborn , Phenotype , Senegal
20.
Emerg Infect Dis ; 21(4): 655-9, 2015 Apr.
Article in English | MEDLINE | ID: mdl-25811307

ABSTRACT

We identified 3 lineages among multidrug-resistant (MDR) Salmonella enterica serotype Typhi isolates in the Gulf of Guinea region in Africa during the 2000s. However, the MDR H58 haplotype, which predominates in southern Asia and Kenya, was not identified. MDR quinolone-susceptible isolates contained a 190-kb incHI1 pST2 plasmid or a 50-kb incN pST3 plasmid.


Subject(s)
Anti-Bacterial Agents/pharmacology , Drug Resistance, Multiple, Bacterial , Salmonella typhi/drug effects , Typhoid Fever/epidemiology , Typhoid Fever/microbiology , Genetic Variation , Geography , Guinea/epidemiology , Haplotypes , Humans , Microbial Sensitivity Tests , Polymorphism, Single Nucleotide , Salmonella typhi/genetics
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