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1.
BMC Res Notes ; 17(1): 68, 2024 Mar 09.
Artículo en Inglés | MEDLINE | ID: mdl-38461329

RESUMEN

BACKGROUND: Following WHO guidelines, microscopy is the gold standard for malaria diagnosis in endemic countries. The Parasitology-Mycology laboratory (LPM) is the National Reference Laboratory and is currently undergoing ISO 15189 accreditation. In this context, we assessed the performance of the laboratory by confirming the reliability and the accuracy of results obtained in accordance with the requirements of the ISO 15189 standards. This study aimed to verify the method of microscopic diagnosis of malaria at the LPM, in the Aristide Le Dantec hospital (HALD) in Dakar, Senegal. METHODS: This is a validation/verification study conducted from June to August 2020. Twenty (20) microscopic slides of thick/thin blood smear with known parasite densities (PD) selected from the Cheick Anta Diop University malaria slide bank in Dakar were used for this assessment. Six (6) were used to assess microscopists' ability to determine PD and fourteen (14) slides were used for detection (positive vs negative) and identification of parasites. Four (4) LPM-HALD microscopists read and recorded their results on prepared sheets. Data analysis was done with Microsoft Excel 2010 software. RESULTS: A minimum threshold of 50% concordance was used for comparison. Of the twenty (20) slides read, 100% concordance was obtained on eight (8) detection (positive vs negative) slides. Four (4) out of the six (6) parasite density evaluation slides obtained a concordance of less than 50%. Thirteen (13) out of the fourteen (14) identification slides obtained a concordance greater than 50%. Only one (1) identification slide obtained zero agreement from the microscopists. For species identification a concordance greater than 80% was noted and the microscopists obtained scores between 0.20 and 0.4 on a scale of 0 to 1 for parasite density reading. The microscopists obtained 100% precision, sensitivity, specificity and both negative and positive predictive values. CONCLUSION: This work demonstrated that the microscopic method of malaria diagnosis used in the LPM/HALD is in accordance with the requirements of WHO and ISO 15189. Further training of microscopists may be needed to maintain competency.


Asunto(s)
Malaria , Humanos , Senegal , Reproducibilidad de los Resultados , Malaria/diagnóstico , Malaria/parasitología , Laboratorios , Hospitales Universitarios
2.
Nat Commun ; 15(1): 747, 2024 Jan 25.
Artículo en Inglés | MEDLINE | ID: mdl-38272885

RESUMEN

The worldwide decline in malaria incidence is revealing the extensive burden of non-malarial febrile illness (NMFI), which remains poorly understood and difficult to diagnose. To characterize NMFI in Senegal, we collected venous blood and clinical metadata in a cross-sectional study of febrile patients and healthy controls in a low malaria burden area. Using 16S and untargeted sequencing, we detected viral, bacterial, or eukaryotic pathogens in 23% (38/163) of NMFI cases. Bacteria were the most common, with relapsing fever Borrelia and spotted fever Rickettsia found in 15.5% and 3.8% of cases, respectively. Four viral pathogens were found in a total of 7 febrile cases (3.5%). Sequencing also detected undiagnosed Plasmodium, including one putative P. ovale infection. We developed a logistic regression model that can distinguish Borrelia from NMFIs with similar presentation based on symptoms and vital signs (F1 score: 0.823). These results highlight the challenge and importance of improved diagnostics, especially for Borrelia, to support diagnosis and surveillance.


Asunto(s)
Borrelia , Malaria , Plasmodium , Humanos , Senegal/epidemiología , Estudios Transversales , Malaria/diagnóstico , Malaria/epidemiología , Fiebre/epidemiología , Borrelia/genética
3.
medRxiv ; 2023 Aug 25.
Artículo en Inglés | MEDLINE | ID: mdl-37662407

RESUMEN

The worldwide decline in malaria incidence is revealing the extensive burden of non-malarial febrile illness (NMFI), which remains poorly understood and difficult to diagnose. To characterize NMFI in Senegal, we collected venous blood and clinical metadata from febrile patients and healthy controls in a low malaria burden area. Using 16S and unbiased sequencing, we detected viral, bacterial, or eukaryotic pathogens in 29% of NMFI cases. Bacteria were the most common, with relapsing fever Borrelia and spotted fever Rickettsia found in 15% and 3.7% of cases, respectively. Four viral pathogens were found in a total of 7 febrile cases (3.5%). Sequencing also detected undiagnosed Plasmodium, including one putative P. ovale infection. We developed a logistic regression model to distinguish Borrelia from NMFIs with similar presentation based on symptoms and vital signs. These results highlight the challenge and importance of improved diagnostics, especially for Borrelia, to support diagnosis and surveillance.

4.
Trop Parasitol ; 13(1): 34-39, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-37415757

RESUMEN

Context: Toxoplasma gondii and rubella virus are microorganisms that can cause intrauterine infections and congenital anomalies in the fetus. Data regarding the simultaneous seroprevalence of these infections are not available in Senegal. Aims: This study aimed to determine for the first time the simultaneous seroprevalence of toxoplasmosis and rubella among pregnant women in Dakar. Materials and Methods: In this retrospective study, anti-Toxoplasma and anti-rubella antibodies were analyzed in the serum samples obtained from pregnant women receiving prenatal care at Military Hospital of Ouakam between 2016 and 2021 using a chemiluminescent microparticle immunoassay for the quantitative determination of immunoglobulin G (IgG) and IgM antibodies to Toxoplasma gondii and rubella in human serum. Results: Overall, data from 2589 women were analyzed. The median age was 29 years (interquartile range: 23.14-34.86). Serum IgG and IgM were positive for T. gondii with 35.84% and 1.66%, respectively. Rubella seroprevalence was 87.14% and 0.35%, respectively, for IgG and IgM. Seroprevalence of toxoplasmosis increases significantly with age and study period. For rubella infection, the highest seroprevalence rates were noted in the youngest age group and at the end of the study period. Conclusions: Data from this first-time study regarding simultaneous seroprevalence of toxoplasmosis and rubella among pregnant women in Senegal indicate a continuing high risk of congenital toxoplasmosis and congenital rubella syndrome in Dakar. Further studies are needed to fully assess the efficacy of rubella vaccination in women of childbearing age.

5.
Int J Dermatol ; 62(9): 1131-1141, 2023 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-37340531

RESUMEN

BACKGROUND: Cutaneous fungal infections are very common, especially in poorer communities and with intercurrent HIV infection. Determining the fungal pathogen in skin-related fungal neglected tropical diseases (NTDs) determines optimal therapy. We undertook a country survey across many African countries to determine the diagnostic capacity for skin fungal diseases. METHODS: A detailed questionnaire was delivered to country contacts to collect data on availability, frequency, and location of testing for key diagnostic procedures and followed up with 2 rounds of validation by video call and by confirmation of individual country data confirmation by email. RESULTS: Of 47 countries with data, seven (15%) and 21 (45%) do not offer skin biopsy in the public or private sector, respectively, but 22 (46%) countries do it regularly, mostly in university hospitals. Direct microscopy is often performed in 20 of 48 (42%) countries in the public sector and not done in 10 (21%). Fungal cultures are often performed in 21 of 48 (44%) countries in the public sector but not done in nine (20%) or 21 (44%) in either public or private facilities. Histopathological examination of tissue is frequently used in 19 of 48 (40%) countries but not in nine (20%) countries in the public sector. The cost of diagnostics to patients was a major limiting factor in usage. CONCLUSION: Major improvements in the availability and use of diagnostic tests for skin, hair, and nail fungal disease are urgently needed across Africa.


Asunto(s)
Dermatomicosis , Infecciones por VIH , Malaria , Humanos , África , Dermatomicosis/diagnóstico , Sector Privado
6.
medRxiv ; 2023 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-37163114

RESUMEN

Drug resistance in Plasmodium falciparum is a major threat to malaria control efforts. We analyzed data from two decades (2000-2020) of continuous molecular surveillance of P. falciparum parasite strains in Senegal to determine how historical changes in drug administration policy may have affected parasite evolution. We profiled several known drug resistance markers and their surrounding haplotypes using a combination of single nucleotide polymorphism (SNP) molecular surveillance and whole-genome sequence (WGS) based population genomics. We observed rapid changes in drug resistance markers associated with the withdrawal of chloroquine and introduction of sulfadoxine-pyrimethamine in 2003. We also observed a rapid increase in Pfcrt K76T and decline in Pfdhps A437G starting in 2014, which we hypothesize may reflect changes in resistance or fitness caused by seasonal malaria chemoprevention (SMC). Parasite populations evolve rapidly in response to drug use, and SMC preventive efficacy should be closely monitored.

7.
Sci Rep ; 12(1): 22175, 2022 12 22.
Artículo en Inglés | MEDLINE | ID: mdl-36550362

RESUMEN

Sero-surveillance can monitor and project disease burden and risk. However, SARS-CoV-2 antibody test results can produce false positive results, limiting their efficacy as a sero-surveillance tool. False positive SARS-CoV-2 antibody results are associated with malaria exposure, and understanding this association is essential to interpret sero-surveillance results from malaria-endemic countries. Here, pre-pandemic samples from eight malaria endemic and non-endemic countries and four continents were tested by ELISA to measure SARS-CoV-2 Spike S1 subunit reactivity. Individuals with acute malaria infection generated substantial SARS-CoV-2 reactivity. Cross-reactivity was not associated with reactivity to other human coronaviruses or other SARS-CoV-2 proteins, as measured by peptide and protein arrays. ELISAs with deglycosylated and desialated Spike S1 subunits revealed that cross-reactive antibodies target sialic acid on N-linked glycans of the Spike protein. The functional activity of cross-reactive antibodies measured by neutralization assays showed that cross-reactive antibodies did not neutralize SARS-CoV-2 in vitro. Since routine use of glycosylated or sialated assays could result in false positive SARS-CoV-2 antibody results in malaria endemic regions, which could overestimate exposure and population-level immunity, we explored methods to increase specificity by reducing cross-reactivity. Overestimating population-level exposure to SARS-CoV-2 could lead to underestimates of risk of continued COVID-19 transmission in sub-Saharan Africa.


Asunto(s)
COVID-19 , Malaria , Humanos , Glicoproteína de la Espiga del Coronavirus , SARS-CoV-2 , Anticuerpos Antivirales , Reacciones Cruzadas , Ácido N-Acetilneuramínico , Epítopos
8.
PNAS Nexus ; 1(4): pgac187, 2022 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-36246152

RESUMEN

Multiple-strain (polygenomic) infections are a ubiquitous feature of Plasmodium falciparum parasite population genetics. Under simple assumptions of superinfection, polygenomic infections are hypothesized to be the result of multiple infectious bites. As a result, polygenomic infections have been used as evidence of repeat exposure and used to derive genetic metrics associated with high transmission intensity. However, not all polygenomic infections are the result of multiple infectious bites. Some result from the transmission of multiple, genetically related strains during a single infectious bite (cotransmission). Superinfection and cotransmission represent two distinct transmission processes, and distinguishing between the two could improve inferences regarding parasite transmission intensity. Here, we describe a new metric, R H, that utilizes the correlation in allelic state (heterozygosity) within polygenomic infections to estimate the likelihood that the observed complexity resulted from either superinfection or cotransmission. R H is flexible and can be applied to any type of genetic data. As a proof of concept, we used R H to quantify polygenomic relatedness and estimate cotransmission and superinfection rates from a set of 1,758 malaria infections genotyped with a 24 single nucleotide polymorphism (SNP) molecular barcode. Contrary to expectation, we found that cotransmission was responsible for a significant fraction of 43% to 53% of the polygenomic infections collected in three distinct epidemiological regions in Senegal. The prediction that polygenomic infections frequently result from cotransmission stresses the need to incorporate estimates of relatedness within polygenomic infections to ensure the accuracy of genomic epidemiology surveillance data for informing public health activities.

9.
Viruses ; 13(8)2021 08 13.
Artículo en Inglés | MEDLINE | ID: mdl-34452470

RESUMEN

While investigating a signal of adaptive evolution in humans at the gene LARGE, we encountered an intriguing finding by Dr. Stefan Kunz that the gene plays a critical role in Lassa virus binding and entry. This led us to pursue field work to test our hypothesis that natural selection acting on LARGE-detected in the Yoruba population of Nigeria-conferred resistance to Lassa Fever in some West African populations. As we delved further, we conjectured that the "emerging" nature of recently discovered diseases like Lassa fever is related to a newfound capacity for detection, rather than a novel viral presence, and that humans have in fact been exposed to the viruses that cause such diseases for much longer than previously suspected. Dr. Stefan Kunz's critical efforts not only laid the groundwork for this discovery, but also inspired and catalyzed a series of events that birthed Sentinel, an ambitious and large-scale pandemic prevention effort in West Africa. Sentinel aims to detect and characterize deadly pathogens before they spread across the globe, through implementation of its three fundamental pillars: Detect, Connect, and Empower. More specifically, Sentinel is designed to detect known and novel infections rapidly, connect and share information in real time to identify emerging threats, and empower the public health community to improve pandemic preparedness and response anywhere in the world. We are proud to dedicate this work to Stefan Kunz, and eagerly invite new collaborators, experts, and others to join us in our efforts.


Asunto(s)
Planificación en Desastres , Fiebre de Lassa/epidemiología , Virus Lassa/fisiología , África Occidental/epidemiología , Planificación en Desastres/métodos , Humanos , Fiebre de Lassa/genética , Fiebre de Lassa/prevención & control , Fiebre de Lassa/virología , Virus Lassa/genética , N-Acetilglucosaminiltransferasas/genética , N-Acetilglucosaminiltransferasas/inmunología , Nigeria/epidemiología , Pandemias , Polimorfismo Genético , Receptores Virales/genética , Receptores Virales/inmunología
10.
medRxiv ; 2021 May 12.
Artículo en Inglés | MEDLINE | ID: mdl-34013301

RESUMEN

Individuals with acute malaria infection generated high levels of antibodies that cross-react with the SARS-CoV-2 Spike protein. Cross-reactive antibodies specifically recognized the sialic acid moiety on N-linked glycans of the Spike protein and do not neutralize in vitro SARS-CoV-2. Sero-surveillance is critical for monitoring and projecting disease burden and risk during the pandemic; however, routine use of Spike protein-based assays may overestimate SARS-CoV-2 exposure and population-level immunity in malaria-endemic countries.

11.
Sci Rep ; 11(1): 10321, 2021 05 14.
Artículo en Inglés | MEDLINE | ID: mdl-33990632

RESUMEN

Dengue virus is a major and rapidly growing public health concern in tropic and subtropic regions across the globe. In late 2018, Senegal experienced its largest dengue virus outbreak to date, covering several regions. However, little is known about the genetic diversity of dengue virus (DENV) in Senegal. Here we report complete viral genomes from 17 previously undetected DENV cases from the city of Thiès. In total we identified 19 cases of DENV in a cohort of 198 individuals with fever collected in October and November 2018. We detected 3 co-circulating serotypes; DENV 3 was the most frequent accounting for 11/17 sequences (65%), 4 (23%) were DENV2 and 2 (12%) were DENV1. Sequences were most similar to recent sequences from West Africa, suggesting ongoing local circulation of viral populations; however, detailed inference is limited by the scarcity of available genomic data. We did not find clear associations with reported clinical signs or symptoms, highlighting the importance of testing for diagnosing febrile diseases. Overall, these findings expand the known range of DENV in Senegal, and underscore the need for better genomic characterization of DENV in West Africa.


Asunto(s)
Virus del Dengue/genética , Dengue/virología , Brotes de Enfermedades/estadística & datos numéricos , Adolescente , Adulto , Anciano , Niño , Preescolar , ADN Viral/aislamiento & purificación , Dengue/sangre , Dengue/diagnóstico , Dengue/epidemiología , Virus del Dengue/aislamiento & purificación , Femenino , Genoma Viral , Humanos , Masculino , Persona de Mediana Edad , Epidemiología Molecular , Filogenia , Senegal/epidemiología , Serogrupo , Adulto Joven
12.
Malar J ; 20(1): 38, 2021 Jan 13.
Artículo en Inglés | MEDLINE | ID: mdl-33436004

RESUMEN

BACKGROUND: Characterizing the genetic diversity of malaria parasite populations in different endemic settings (from low to high) could be helpful in determining the effectiveness of malaria interventions. This study compared Plasmodium falciparum parasite population diversity from two sites with low (pre-elimination) and high transmission in Senegal and Nigeria, respectively. METHODS: Parasite genomic DNA was extracted from 187 dried blood spot collected from confirmed uncomplicated P. falciparum malaria infected patients in Senegal (94) and Nigeria (93). Allelic polymorphism at merozoite surface protein 1 (msp1) and merozoite surface protein- 2 (msp2) genes were assessed by nested PCR. RESULTS: The most frequent msp1 and msp2 allelic families are the K1 and IC3D7 allelotypes in both Senegal and Nigeria. Multiplicity of infection (MOI) of greater that 1 and thus complex infections was common in both study sites in Senegal (Thies:1.51/2.53; Kedougou:2.2/2.0 for msp1/2) than in Nigeria (Gbagada: 1.39/1.96; Oredo: 1.35/1.75]). The heterozygosity of msp1 gene was higher in P. falciparum isolates from Senegal (Thies: 0.62; Kedougou: 0.53) than isolates from Nigeria (Gbagada: 0.55; Oredo: 0.50). In Senegal, K1 alleles was associated with heavy than with moderate parasite density. Meanwhile, equal proportions of K1 were observed in both heavy and moderate infection types in Nigeria. The IC3D7 subtype allele of the msp2 family was the most frequent in heavily parasitaemic individuals from both countries than in the moderately infected participants. CONCLUSION: The unexpectedly low genetic diversity of infections high endemic Nigerian setting compared to the low endemic settings in Senegal is suggestive of possible epidemic outbreak in Nigeria.


Asunto(s)
Antígenos de Protozoos/genética , Variación Genética , Malaria Falciparum/parasitología , Proteína 1 de Superficie de Merozoito/genética , Plasmodium falciparum/genética , Proteínas Protozoarias/genética , Adolescente , Adulto , Anciano , Niño , Preescolar , Femenino , Humanos , Lactante , Malaria Falciparum/epidemiología , Masculino , Persona de Mediana Edad , Nigeria/epidemiología , Senegal/epidemiología , Adulto Joven
13.
Malar J ; 16(1): 328, 2017 08 10.
Artículo en Inglés | MEDLINE | ID: mdl-28797261

RESUMEN

BACKGROUND: This study was initiated from the observation that prevalence of malaria obtained with rapid diagnostic test (RDT) (CareStart™Malaria HRP2/pLDH Combo Test) was higher than in microscopy in a malaria low transmission area of Senegal. PCR was then performed to evaluate the performance of the RDT compared to microscopy in clinical settings. METHODS: The study included 215 patients suspected of malaria in two peri-urban area of Dakar. Finger-pick blood samples were tested using RDT (CareStart™Malaria HRP2/pLDH Combo Test). Venous blood samples were collected for light microscopy and PCR (gold standard). Sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) were calculated as performance characteristics. RESULTS: Considering PCR as the gold standard, CareStart™RDT showed high sensitivity (97.3%) and specificity (94.1%) with PPV and NPV of 97.3 and 94.1%, respectively, while microscopy had a sensitivity and specificity of 93.2 and 100%, respectively, and PPV and NPV of 100 and 87.2%, respectively. CONCLUSIONS: Malaria CareStart™RDT test demonstrated a superior sensitivity compared to microscopy, which is the gold standard for malaria diagnosis. CareStart™RDT could be a useful tool in individuals suspected of malaria even in areas where prevalence is low.


Asunto(s)
Pruebas Diagnósticas de Rutina/normas , Malaria Falciparum/diagnóstico , Adolescente , Adulto , Anciano , Niño , Femenino , Humanos , Malaria Falciparum/epidemiología , Masculino , Microscopía/normas , Persona de Mediana Edad , Reacción en Cadena de la Polimerasa/normas , Valor Predictivo de las Pruebas , Prevalencia , Proteínas Protozoarias/análisis , Senegal/epidemiología , Sensibilidad y Especificidad , Adulto Joven
14.
Malar J ; 16(1): 153, 2017 Apr 19.
Artículo en Inglés | MEDLINE | ID: mdl-28420422

RESUMEN

BACKGROUND: Emergence and spread of drug resistance to every anti-malarial used to date, creates an urgent need for development of sensitive, specific and field-deployable molecular tools for detection and surveillance of validated drug resistance markers. Such tools would allow early detection of mutations in resistance loci. The aim of this study was to compare common population signatures and drug resistance marker frequencies between two populations with different levels of malaria endemicity and history of anti-malarial drug use: Tanzania and Sénégal. This was accomplished by implementing a high resolution melting assay to study molecular markers of drug resistance as compared to polymerase chain reaction-restriction fragment length polymorphism (PCR/RFLP) methodology. METHODS: Fifty blood samples were collected each from a lowly malaria endemic site (Sénégal), and a highly malaria endemic site (Tanzania) from patients presenting with uncomplicated Plasmodium falciparum malaria at clinic. Data representing the DHFR were derived using both PCR-RFLP and HRM assay; while genotyping data representing the DHPS were evaluated in Senegal and Tanzania using HRM. Msp genotyping analysis was used to characterize the multiplicity of infection in both countries. RESULTS: A high prevalence of samples harbouring mutant DHFR alleles was observed in both population using both genotyping techniques. HRM was better able to detect mixed alleles compared to PCR/RFLP for DHFR codon 51 in Tanzania; and only HRM was able to detect mixed infections from Senegal. A high prevalence of mutant alleles in DHFR (codons 51, 59, 108) and DHPS (codon 437) were found among samples from Sénégal while no mutations were observed at DHPS codons 540 and 581, from both countries. Overall, the frequency of samples harbouring either a single DHFR mutation (S108N) or double mutation in DHFR (C59R/S108N) was greater in Sénégal compared to Tanzania. CONCLUSION: Here the results demonstrate that HRM is a rapid, sensitive, and field-deployable alternative technique to PCR-RFLP genotyping that is useful in populations harbouring more than one parasite genome (polygenomic infections). In this study, a high levels of resistance polymorphisms was observed in both dhfr and dhps, among samples from Tanzania and Sénégal. A routine monitoring by molecular markers can be a way to detect emergence of resistance involving a change in the treatment policy.


Asunto(s)
Dihidropteroato Sintasa/genética , Resistencia a Medicamentos , Técnicas de Diagnóstico Molecular/métodos , Plasmodium/enzimología , Sistemas de Atención de Punto , Tetrahidrofolato Deshidrogenasa/genética , Temperatura de Transición , Adolescente , Niño , Preescolar , Genotipo , Técnicas de Genotipaje/métodos , Humanos , Malaria Falciparum/parasitología , Plasmodium/efectos de los fármacos , Plasmodium/genética , Reacción en Cadena de la Polimerasa , Polimorfismo de Longitud del Fragmento de Restricción , Senegal , Tanzanía , Adulto Joven
15.
Malar J ; 16(1): 24, 2017 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-28077149

RESUMEN

BACKGROUND: West African tick-borne relapsing fever (TBRF) due to Borrelia crocidurae and malaria are co-endemics in Senegal. Although expected to be high, co-infections are rarely reported. A case of falciparum malaria and B. crocidurae co-infection in a patient from Velingara (South of Senegal) is discussed. CASE: A 28 year-old-male patient presented to Aristide Le Dantec Hospital for recurrent fever. He initially presented to a local post health of Pikine (sub-urban of Dakar) and was diagnosed for malaria on the basis of positive malaria rapid diagnostic test (RDT) specific to Plamodium falciparum. The patient was treated as uncomplicated falciparum malaria. Four days after admission the patient was referred to Le Dantec Hospital. He presented with fever (39 °C), soreness, headache and vomiting. The blood pressure was 120/80 mmHg. The rest of the examination was normal. A thick film from peripheral blood was performed and addressed to the parasitology laboratory of the hospital. Thick film was stained with 10% Giemsa. Trophozoite of P. falciparum was identified at parasite density of 47 parasites per microlitre. The presence of Borrelia was also observed, concluding to malaria co-infection with borreliosis. CONCLUSIONS: Signs of malaria can overlap with signs of borreliosis leading to the misdiagnosis of the latter. Thick and thin smear or QBC test or molecular method may be helpful to detect both Plamodium species and Borrelia. In addition, there is a real need to consider co-infections with other endemics pathogens when diagnosing malaria.


Asunto(s)
Coinfección/diagnóstico , Malaria Falciparum/complicaciones , Malaria Falciparum/diagnóstico , Fiebre Recurrente/complicaciones , Fiebre Recurrente/diagnóstico , Enfermedades por Picaduras de Garrapatas/complicaciones , Enfermedades por Picaduras de Garrapatas/diagnóstico , Adulto , Infecciones Bacterianas , Borrelia , Infecciones por Borrelia , Coinfección/patología , Humanos , Malaria , Malaria Falciparum/patología , Masculino , Fiebre Recurrente/patología , Senegal/epidemiología , Enfermedades por Picaduras de Garrapatas/patología
16.
Malar J ; 16(1): 9, 2017 01 03.
Artículo en Inglés | MEDLINE | ID: mdl-28049489

RESUMEN

BACKGROUND: Expanded malaria control efforts in Sénégal have resulted in increased use of rapid diagnostic tests (RDT) to identify the primary disease-causing Plasmodium species, Plasmodium falciparum. However, the type of RDT utilized in Sénégal does not detect other malaria-causing species such as Plasmodium ovale spp., Plasmodium malariae, or Plasmodium vivax. Consequently, there is a lack of information about the frequency and types of malaria infections occurring in Sénégal. This study set out to better determine whether species other than P. falciparum were evident among patients evaluated for possible malaria infection in Kédougou, Sénégal. METHODS: Real-time polymerase chain reaction speciation assays for P. vivax, P. ovale spp., and P. malariae were developed and validated by sequencing and DNA extracted from 475 Plasmodium falciparum-specific HRP2-based RDT collected between 2013 and 2014 from a facility-based sample of symptomatic patients from two health clinics in Kédougou, a hyper-endemic region in southeastern Sénégal, were analysed. RESULTS: Plasmodium malariae (n = 3) and P. ovale wallikeri (n = 2) were observed as co-infections with P. falciparum among patients with positive RDT results (n = 187), including one patient positive for all three species. Among 288 negative RDT samples, samples positive for P. falciparum (n = 24), P. ovale curtisi (n = 3), P. ovale wallikeri (n = 1), and P. malariae (n = 3) were identified, corresponding to a non-falciparum positivity rate of 2.5%. CONCLUSIONS: These findings emphasize the limitations of the RDT used for malaria diagnosis and demonstrate that non-P. falciparum malaria infections occur in Sénégal. Current RDT used for routine clinical diagnosis do not necessarily provide an accurate reflection of malaria transmission in Kédougou, Sénégal, and more sensitive and specific methods are required for diagnosis and patient care, as well as surveillance and elimination activities. These findings have implications for other malaria endemic settings where species besides P. falciparum may be transmitted and overlooked by control or elimination activities.


Asunto(s)
Malaria/epidemiología , Plasmodium malariae/aislamiento & purificación , Plasmodium ovale/aislamiento & purificación , Plasmodium vivax/aislamiento & purificación , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Niño , Preescolar , Pruebas Diagnósticas de Rutina/métodos , Femenino , Humanos , Lactante , Masculino , Persona de Mediana Edad , Plasmodium malariae/clasificación , Plasmodium malariae/genética , Plasmodium ovale/clasificación , Plasmodium ovale/genética , Plasmodium vivax/clasificación , Plasmodium vivax/genética , Prevalencia , Reacción en Cadena en Tiempo Real de la Polimerasa , Senegal/epidemiología , Sensibilidad y Especificidad , Adulto Joven
17.
Malar J ; 15(1): 433, 2016 08 25.
Artículo en Inglés | MEDLINE | ID: mdl-27562216

RESUMEN

BACKGROUND: The use of artemisinin as a monotherapy resulted in the emergence of artemisinin resistance in 2005 in Southeast Asia. Monitoring of artemisinin combination therapy (ACT) is critical in order to detect and prevent the spread of resistance in endemic areas. Ex vivo studies and genotyping of molecular markers of resistance can be used as part of this routine monitoring strategy. One gene that has been associated in some ACT partner drug resistance is the Plasmodium falciparum multidrug resistance protein 1 (pfmdr1) gene. The purpose of this study was to assess the drug susceptibility of P. falciparum populations from Thiès, Senegal by ex vivo assay and typing molecular markers of resistance to drug components of ACT currently used for treatment. METHODS: The ex vivo susceptibility of 170 P. falciparum isolates to chloroquine, amodiaquine, lumefantrine, artesunate, and artemether was determined using the DAPI ex vivo assay. The high resolution melting technique was used to genotype the pfmdr1 gene at codons 86, 184 and 1246. RESULTS: A significant decrease in IC50 values was observed between 2012 and 2013: from 13.84 to 6.484 for amodiaquine, 173.4 to 113.2 for lumefantrine, and 39.72 to 18.29 for chloroquine, respectively. Increase of the wild haplotype NYD and the decrease of the mutant haplotype NFD (79 and 62.26 %) was also observed. A correlation was observed between the wild type allele Y184 in pfmdr1 and higher IC50 for all drugs, except amodiaquine. CONCLUSION: This study has shown an increase in sensitivity over the span of two transmission seasons, marked by an increase in the WT alleles at pfmdr1. Continuous the monitoring of the ACT used for treatment of uncomplicated malaria will be helpful.


Asunto(s)
Antimaláricos/farmacología , Artemisininas/farmacología , Etanolaminas/farmacología , Fluorenos/farmacología , Frecuencia de los Genes , Haplotipos , Proteínas Asociadas a Resistencia a Múltiples Medicamentos/genética , Plasmodium falciparum/efectos de los fármacos , Selección Genética , Adolescente , Antimaláricos/uso terapéutico , Combinación Arteméter y Lumefantrina , Artemisininas/uso terapéutico , Niño , Preescolar , Combinación de Medicamentos , Etanolaminas/uso terapéutico , Femenino , Fluorenos/uso terapéutico , Genética de Población , Técnicas de Genotipaje , Humanos , Malaria Falciparum/parasitología , Masculino , Plasmodium falciparum/clasificación , Plasmodium falciparum/genética , Senegal , Adulto Joven
18.
Malar J ; 15(1): 429, 2016 Aug 24.
Artículo en Inglés | MEDLINE | ID: mdl-27557982

RESUMEN

BACKGROUND: Plasmodium ovale is rarely described in Senegal. A case of clinical malaria due to P. ovale wallikeri in West Central of Senegal is reported. CASE: A 34-year-old male baker in Dakar, with no significant previous medical history, was admitted to a health clinic with fever and vomiting. Fever had been lasting for 4 days with peaks every 48 h. As monospecific Plasmodium falciparum HRP-2 RDT was negative, he was treated with antibiotics. However, owing to persisting symptoms, he was referred to the emergency unit of the Youssou Mbargane Diop Hospital, Dakar, Senegal. Clinical examination found impaired general condition. All other physical examinations were normal. Laboratory tests showed anaemia (haemoglobin 11.4 g/dl), severe thrombocytopaenia (platelets 30 × 10(9)/mm(3)), leukopenia (3650/mm(3)), lymphocytopenia (650/mm(3)). Renal function was normal as indicated by creatininaemia and uraemia (11 mg/l and 0.25 g/l, respectively) and liver enzymes were slightly elevated (aspartate aminotransferase 77 UI/l and alanine aminotransferase 82 UI/l). Blood smear evaluations in Parasitology Laboratory of Aristide Le Dantec Hospital showed malaria parasites of the species P. ovale with a 0.08 % parasitaemia. Molecular confirmation was done by real time PCR targeting the 18S rRNA gene. The P. ovale infection was further analysed to species level targeting the potra gene and was identified as P. ovale wallikeri. According to the hospital's malaria treatment guidelines for severe malaria, treatment consisted of intravenous quinine at hour 0 (start of treatment) and 24 h after initial treatment, followed by artemether-lumefantrine 24 h later. A negative microscopy was noted on day 3 post-treatment and the patient reported no further symptoms. CONCLUSION: Malaria due to non-falciparum species is probably underestimated in Senegal. RDTs specific to non-falciparum species and/or pan specific RDTs should be included as tools of diagnosis to fight against malaria in Senegal. In addition, a field-deployable molecular tool such as the loop-mediated isothermal amplification can be considered as an additional useful tool to detect low malaria parasite infections and for speciation. In addition, national malaria control policies should consider other non-falciparum species in treatment guidelines, including the provision of primaquine for the treatment of relapsing parasites.


Asunto(s)
Malaria/diagnóstico , Malaria/parasitología , Plasmodium ovale/clasificación , Plasmodium ovale/aislamiento & purificación , Adulto , Antimaláricos/uso terapéutico , Combinación Arteméter y Lumefantrina , Artemisininas/uso terapéutico , ADN Protozoario/química , ADN Protozoario/genética , ADN Ribosómico/química , ADN Ribosómico/genética , Combinación de Medicamentos , Etanolaminas/uso terapéutico , Fluorenos/uso terapéutico , Humanos , Malaria/tratamiento farmacológico , Malaria/patología , Masculino , Microscopía , Plasmodium ovale/genética , Quinina/uso terapéutico , ARN Ribosómico 18S/genética , Senegal , Análisis de Secuencia de ADN
19.
Mycoses ; 58 Suppl 5: 63-9, 2015 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-26449509

RESUMEN

Senegal has a high rate of tuberculosis and a low HIV seropositivity rate and aspergilloma, life-threatening fungal infections, dermatophytosis and mycetoma have been reported in this study. All published epidemiology papers reporting fungal infection rates from Senegal were identified. Where no data existed, we used specific populations at risk and fungal infection frequencies in each to estimate national incidence or prevalence. The results show that tinea capitis is common being found in 25% of children, ~1.5 million. About 191,000 Senegalese women get recurrent vaginal thrush, ≥4 times annually. We estimate 685 incident cases of chronic pulmonary aspergillosis (CPA) following TB and prevalence of 2160 cases. Asthma prevalence in adults varies from 3.2% to 8.2% (mean 5%); 9976 adults have allergic bronchopulmonary aspergillosis (ABPA) and 13,168 have severe asthma with fungal sensitisation (SAFS). Of the 59,000 estimated HIV-positive patients, 366 develop cryptococcal meningitis; 1149 develop Pneumocystis pneumonia and 1946 develop oesophageal candidiasis, in which oral candidiasis (53%) and dermatophytosis (16%) are common. Since 2008-2010, 113 cases of mycetoma were diagnosed. In conclusion, we estimate that 1,743,507 (12.5%) people in Senegal suffer from a fungal infection, excluding oral candidiasis, fungal keratitis, invasive candidiasis or aspergillosis. Diagnostic and treatment deficiencies should be rectified to allow epidemiological studies.


Asunto(s)
Micosis/epidemiología , Infecciones Oportunistas Relacionadas con el SIDA/epidemiología , Adolescente , Adulto , Aspergilosis Broncopulmonar Alérgica/epidemiología , Aspergilosis Broncopulmonar Alérgica/microbiología , Asma/epidemiología , Asma/etiología , Asma/microbiología , Niño , Preescolar , Femenino , Infecciones por VIH/complicaciones , Infecciones por VIH/epidemiología , Humanos , Incidencia , Lactante , Recién Nacido , Masculino , Persona de Mediana Edad , Micetoma/epidemiología , Micetoma/microbiología , Micosis/microbiología , Micosis/mortalidad , Prevalencia , Aspergilosis Pulmonar/diagnóstico , Aspergilosis Pulmonar/epidemiología , Aspergilosis Pulmonar/microbiología , Senegal/epidemiología , Tiña del Cuero Cabelludo/epidemiología , Tiña del Cuero Cabelludo/microbiología , Tuberculosis/complicaciones , Tuberculosis/microbiología , Adulto Joven
20.
Malar J ; 13: 226, 2014 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-24906879

RESUMEN

According to current estimates, Plasmodium malariae is not very common in Senegal, as more than 98% of malaria cases are suspected to be due to Plasmodium falciparum. However, it is possible that other malarial species are being under-reported or misdiagnosed. This is a report of a case of P. malariae in a 30-year-old man previously hospitalized with acute kidney injury after treatment with quinine and re-hospitalized three months later. He was diagnosed with renal cortical necrosis post malaria treatment. Plasmodium malariae was identified with light microscope and confirmed using species-specific small-subunit rRNA (ssrRNA) amplification.The patient was treated for malaria with intravenous quinine for seven days, followed by three days of oral treatment; the bacterial infection was treated using ceftriaxone during the first hospitalization and ciprofloxacin associated with ceftriaxone the second time. He also had four rounds of dialysis after which he partially recovered the renal function. Given the complications that can be caused by P. malariae infection, it should be systematically looked for, even if the predominant species is P. falciparum in Senegal.


Asunto(s)
Lesión Renal Aguda/diagnóstico , Lesión Renal Aguda/patología , Malaria/complicaciones , Malaria/parasitología , Plasmodium malariae/aislamiento & purificación , Adulto , Antibacterianos/uso terapéutico , Antimaláricos/uso terapéutico , Infecciones Bacterianas/diagnóstico , Infecciones Bacterianas/tratamiento farmacológico , Ceftriaxona/uso terapéutico , Humanos , Malaria/diagnóstico , Malaria/tratamiento farmacológico , Masculino , Microscopía , Técnicas de Amplificación de Ácido Nucleico , Quinina/uso terapéutico , ARN Ribosómico 18S/genética , Diálisis Renal , Senegal , Resultado del Tratamiento
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