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1.
Lancet ; 394(10200): 757-779, 2019 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-31257127

RESUMO

BACKGROUND: Pneumonia is the leading cause of death among children younger than 5 years. In this study, we estimated causes of pneumonia in young African and Asian children, using novel analytical methods applied to clinical and microbiological findings. METHODS: We did a multi-site, international case-control study in nine study sites in seven countries: Bangladesh, The Gambia, Kenya, Mali, South Africa, Thailand, and Zambia. All sites enrolled in the study for 24 months. Cases were children aged 1-59 months admitted to hospital with severe pneumonia. Controls were age-group-matched children randomly selected from communities surrounding study sites. Nasopharyngeal and oropharyngeal (NP-OP), urine, blood, induced sputum, lung aspirate, pleural fluid, and gastric aspirates were tested with cultures, multiplex PCR, or both. Primary analyses were restricted to cases without HIV infection and with abnormal chest x-rays and to controls without HIV infection. We applied a Bayesian, partial latent class analysis to estimate probabilities of aetiological agents at the individual and population level, incorporating case and control data. FINDINGS: Between Aug 15, 2011, and Jan 30, 2014, we enrolled 4232 cases and 5119 community controls. The primary analysis group was comprised of 1769 (41·8% of 4232) cases without HIV infection and with positive chest x-rays and 5102 (99·7% of 5119) community controls without HIV infection. Wheezing was present in 555 (31·7%) of 1752 cases (range by site 10·6-97·3%). 30-day case-fatality ratio was 6·4% (114 of 1769 cases). Blood cultures were positive in 56 (3·2%) of 1749 cases, and Streptococcus pneumoniae was the most common bacteria isolated (19 [33·9%] of 56). Almost all cases (98·9%) and controls (98·0%) had at least one pathogen detected by PCR in the NP-OP specimen. The detection of respiratory syncytial virus (RSV), parainfluenza virus, human metapneumovirus, influenza virus, S pneumoniae, Haemophilus influenzae type b (Hib), H influenzae non-type b, and Pneumocystis jirovecii in NP-OP specimens was associated with case status. The aetiology analysis estimated that viruses accounted for 61·4% (95% credible interval [CrI] 57·3-65·6) of causes, whereas bacteria accounted for 27·3% (23·3-31·6) and Mycobacterium tuberculosis for 5·9% (3·9-8·3). Viruses were less common (54·5%, 95% CrI 47·4-61·5 vs 68·0%, 62·7-72·7) and bacteria more common (33·7%, 27·2-40·8 vs 22·8%, 18·3-27·6) in very severe pneumonia cases than in severe cases. RSV had the greatest aetiological fraction (31·1%, 95% CrI 28·4-34·2) of all pathogens. Human rhinovirus, human metapneumovirus A or B, human parainfluenza virus, S pneumoniae, M tuberculosis, and H influenzae each accounted for 5% or more of the aetiological distribution. We observed differences in aetiological fraction by age for Bordetella pertussis, parainfluenza types 1 and 3, parechovirus-enterovirus, P jirovecii, RSV, rhinovirus, Staphylococcus aureus, and S pneumoniae, and differences by severity for RSV, S aureus, S pneumoniae, and parainfluenza type 3. The leading ten pathogens of each site accounted for 79% or more of the site's aetiological fraction. INTERPRETATION: In our study, a small set of pathogens accounted for most cases of pneumonia requiring hospital admission. Preventing and treating a subset of pathogens could substantially affect childhood pneumonia outcomes. FUNDING: Bill & Melinda Gates Foundation.


Assuntos
Hospitalização/estatística & dados numéricos , Pneumonia Bacteriana/epidemiologia , Pneumonia Viral/epidemiologia , Bangladesh/epidemiologia , Teorema de Bayes , Estudos de Casos e Controles , Pré-Escolar , Feminino , Gâmbia/epidemiologia , Infecções por HIV/epidemiologia , Haemophilus influenzae tipo b/isolamento & purificação , Humanos , Lactente , Recém-Nascido , Quênia/epidemiologia , Masculino , Mali/epidemiologia , Pneumonia , Vírus Sinciciais Respiratórios/isolamento & purificação , Índice de Gravidade de Doença , África do Sul/epidemiologia , Streptococcus pneumoniae/isolamento & purificação , Tailândia/epidemiologia , Zâmbia/epidemiologia
3.
mSphere ; 4(2)2019 03 20.
Artigo em Inglês | MEDLINE | ID: mdl-30894432

RESUMO

The repetitive interspersed family (RIFIN) and the subtelomeric variable open reading frame (STEVOR) family represent two of three major Plasmodium falciparum variant surface antigen families involved in malaria pathogenesis and immune evasion and are potential targets in the development of natural immunity. Protein and peptide microarrays populated with RIFINs and STEVORs associated with severe malaria vulnerability in Malian children were probed with adult and pediatric sera to identify epitopes that reflect malaria exposure. Adult sera recognized and reacted with greater intensity to all STEVOR proteins than pediatric sera did. Serorecognition of and seroreactivity to peptides within the semiconserved domain of STEVORs increased with age and seasonal malaria exposure, while serorecognition and seroreactivity increased for the semiconserved and second hypervariable domains of RIFINs only with age. Serologic responses to RIFIN and STEVOR peptides within the semiconserved domains may play a role in natural immunity to severe malaria.IMPORTANCE Malaria, an infectious disease caused by the parasite Plasmodium falciparum, causes nearly 435,000 deaths annually worldwide. RIFINs and STEVORs are two variant surface antigen families that are involved in malaria pathogenesis and immune evasion. Recent work has shown that a lack of humoral immunity to these proteins is associated with severe malaria vulnerability in Malian children. This is the first study to have compared serologic responses of children and adults to RIFINs and STEVORs in settings of malaria endemicity and to examine such serologic responses before and after a clinical malaria episode. Using microarrays, we determined that the semiconserved domains in these two parasite variant surface antigen families harbor peptides whose seroreactivity reflects malaria exposure. A similar approach has the potential to illuminate the role of variant surface antigens in the development of natural immunity to clinical malaria. Potential vaccines for severe malaria should include consideration of peptides within the semiconserved domains of RIFINs and STEVORs.


Assuntos
Anticorpos Antiprotozoários/imunologia , Antígenos de Protozoários/imunologia , Sequências Repetitivas Dispersas/imunologia , Malária/imunologia , Adolescente , Adulto , Fatores Etários , Antígenos de Protozoários/genética , Criança , Pré-Escolar , Ensaios Clínicos Fase I como Assunto , Ensaios Clínicos Fase II como Assunto , Doenças Endêmicas , Feminino , Humanos , Imunidade Inata , Lactente , Malária/sangue , Masculino , Mali/epidemiologia , Pessoa de Meia-Idade , Peptídeos/genética , Peptídeos/imunologia , Plasmodium falciparum , Análise Serial de Proteínas , Adulto Jovem
4.
PLoS One ; 14(1): e0209966, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30608964

RESUMO

African populations are characterized by high degree of genetic diversity. This high genetic diversity could result from the natural selection pressure. Several studies have described an association between some genetic diversities and difference of susceptibility to infectious diseases like malaria. It seems therefore important to consider genetic diversity impact when interpreting results of clinical trials in malaria endemic areas. This study aimed to determine the genetic polymorphism with erythrocyte traits in different populations of malaria endemic area in Mali. The cross-sectional surveys were carried out in different ethnic groups living in malaria endemic areas in Mali. Six milliliters of whole blood were collected in EDTA vials from each participant after informed consent has been obtained. The ABO, RH, Kell, MNSs, Kidd and Duffy systems phenotypes were assessed by the technique of gel filtration. A total of 231 subjects were included from six villages. The blood groups phenotypes O (40.7%) and A (31.2%) were more frequent with respective allele frequencies of 0.65 and 0.21. In the RH system the haplotypes R0 (0.55), r (0.20) and R1 (0.13) were the most frequent. Seven percent (7%) of Duffy positive and 4% of Glycophorin B deficiency (S-s-) were observed among participants. All participants were Kell negative. ABO and RH systems were polymorphic in these ethnic groups in Mali. Their implication in susceptibility to malaria should be taken into account in clinical trials interpretation, and for prevention of blood transfusion risks during anemia frequently caused by malaria in children.


Assuntos
Eritrócitos/metabolismo , Predisposição Genética para Doença/genética , Malária/genética , Sistema do Grupo Sanguíneo ABO/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Alelos , Criança , Pré-Escolar , Estudos Transversais , Feminino , Frequência do Gene/genética , Haplótipos/genética , Humanos , Masculino , Mali/epidemiologia , Pessoa de Meia-Idade , Fenótipo , Polimorfismo Genético/genética , Adulto Jovem
5.
PLoS Negl Trop Dis ; 13(1): e0007064, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30699120

RESUMO

BACKGROUND: Mali has become increasingly interested in the evaluation of transmission of both Wuchereria bancrofti and Onchocerca volvulus as prevalences of both infections move toward their respective elimination targets. The SD Bioline Onchocerciasis/LF IgG4 Rapid Test was used in 2 evaluation units (EU) to assess its performance as an integrated surveillance tool for elimination of lymphatic filariasis (LF) and onchocerciasis. METHODOLOGY/PRINCIPAL FINDINGS: A cross sectional survey with SD Bioline Onchocerciasis/LF IgG4 Rapid Test was piggy-backed onto a transmission assessment survey (TAS) (using the immunochromatographic card test (ICT) Binax Filariasis Now test for filarial adult circulating antigen (CFA) detection) for LF in Mali among 6-7 year old children in 2016 as part of the TAS in two EUs namely Kadiolo-Kolondieba in the region of Sikasso and Bafoulabe -Kita-Oussoubidiagna-Yelimane in the region of Kayes. In the EU of Kadiolo- Kolondieba, of the 1,625 children tested, the overall prevalence of W. bancrofti CFA was 0.62% (10/1,625) [CI = 0.31-1.09]; while that of IgG4 to Wb123 was 0.19% (3/1,600) [CI = 0.04-0.50]. The number of positives tested with the two tests were statistically comparable (p = 0.09). In the EU of Bafoulabe-Kita-Oussoubidiagna-Yelimane, an overall prevalence of W. bancrofti CFA was 0% (0/1,700) and that of Wb123 IgG4 antibody was 0.06% (1/1,700), with no statistically significant difference between the two rates (p = 0.99). In the EU of Kadiolo- Kolondieba, the prevalence of Ov16-specific IgG4 was 0.19% (3/1,600) [CI = 0.04-0.50]. All 3 positives were in the previously O. volvulus-hyperendemic district of Kolondieba. In the EU of Bafoulabe-Kita-Oussoubidiagna-Yelimane, an overall prevalence of Ov16-specific IgG4 was 0.18% (3/1,700) [CI = 0.04-0.47]. These 3 Ov16 IgG4 positives were from previously O.volvulus-mesoendemic district of Kita. CONCLUSIONS/SIGNIFICANCE: The SD Bioline Onchocerciasis/LF IgG4 Rapid test appears to be a good tool for integrated exposure measures of LF and onchocerciasis in co-endemic areas.


Assuntos
Anticorpos Anti-Helmínticos/imunologia , Filariose Linfática/imunologia , Imunoglobulina G/imunologia , Onchocerca volvulus/imunologia , Oncocercose/imunologia , Wuchereria bancrofti/imunologia , Animais , Anticorpos Anti-Helmínticos/sangue , Criança , Estudos Transversais , Filariose Linfática/sangue , Filariose Linfática/epidemiologia , Filariose Linfática/parasitologia , Humanos , Imunoglobulina G/sangue , Testes Imunológicos , Mali/epidemiologia , Doenças Negligenciadas/sangue , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/imunologia , Doenças Negligenciadas/parasitologia , Oncocercose/sangue , Oncocercose/epidemiologia , Oncocercose/parasitologia , Estudos Soroepidemiológicos
6.
N Engl J Med ; 380(23): 2197-2206, 2019 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-30699301

RESUMO

BACKGROUND: Mass administration of azithromycin for trachoma control led to a sustained reduction in all-cause mortality among Ethiopian children. Whether the addition of azithromycin to the monthly sulfadoxine-pyrimethamine plus amodiaquine used for seasonal malaria chemoprevention could reduce mortality and morbidity among African children was unclear. METHODS: We randomly assigned children 3 to 59 months of age, according to household, to receive either azithromycin or placebo, together with sulfadoxine-pyrimethamine plus amodiaquine, during the annual malaria-transmission season in Burkina Faso and Mali. The drug combinations were administered in four 3-day cycles, at monthly intervals, for three successive seasons. The primary end point was death or hospital admission for at least 24 hours that was not due to trauma or elective surgery. Data were recorded by means of active and passive surveillance. RESULTS: In July 2014, a total of 19,578 children were randomly assigned to receive seasonal malaria chemoprevention plus either azithromycin (9735 children) or placebo (9843 children); each year, children who reached 5 years of age exited the trial and new children were enrolled. In the intention-to-treat analysis, the overall number of deaths and hospital admissions during three malaria-transmission seasons was 250 in the azithromycin group and 238 in the placebo group (events per 1000 child-years at risk, 24.8 vs. 23.5; incidence rate ratio, 1.1; 95% confidence interval [CI], 0.88 to 1.3). Results were similar in the per-protocol analysis. The following events occurred less frequently with azithromycin than with placebo: gastrointestinal infections (1647 vs. 1985 episodes; incidence rate ratio, 0.85; 95% CI, 0.79 to 0.91), upper respiratory tract infections (4893 vs. 5763 episodes; incidence rate ratio, 0.85; 95% CI, 0.81 to 0.90), and nonmalarial febrile illnesses (1122 vs. 1424 episodes; incidence rate ratio, 0.79; 95% CI, 0.73 to 0.87). The prevalence of malaria parasitemia and incidence of adverse events were similar in the two groups. CONCLUSIONS: Among children in Burkina Faso and Mali, the addition of azithromycin to the antimalarial agents used for seasonal malaria chemoprevention did not result in a lower incidence of death or hospital admission that was not due to trauma or surgery than antimalarial agents plus placebo, although a lower disease burden was noted with azithromycin than with placebo. (Funded by the Joint Global Health Trials scheme; ClinicalTrials.gov number, NCT02211729.).


Assuntos
Antibacterianos/uso terapêutico , Antimaláricos/uso terapêutico , Azitromicina/uso terapêutico , Mortalidade da Criança , Hospitalização/estatística & dados numéricos , Malária/prevenção & controle , Amodiaquina/uso terapêutico , Burkina Faso/epidemiologia , Pré-Escolar , Esquema de Medicação , Combinação de Medicamentos , Quimioterapia Combinada , Feminino , Humanos , Incidência , Lactente , Mortalidade Infantil , Malária/mortalidade , Masculino , Mali/epidemiologia , Administração Massiva de Medicamentos , Parasitemia/tratamento farmacológico , Pirimetamina/uso terapêutico , Sulfadoxina/uso terapêutico
7.
Parasitol Int ; 68(1): 87-91, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30342119

RESUMO

Proteins coating Plasmodium merozoite surface and secreted from its apical organelles are considered as promising vaccine candidates for blood-stage malaria. The rhoptry neck protein 12 of Plasmodium falciparum (PfRON12) was recently reported as a protein specifically expressed in schizonts and localized to the rhoptry neck of merozoites. Here, we assessed its potential as a vaccine candidate. We expressed a recombinant PfRON12 protein by a wheat germ cell-free system to obtain anti-PfRON12 antibody. Immunoblot analysis of schizont lysates detected a single band at approximately 40 kDa under reducing conditions, consistent with the predicted molecular weight. Additionally, anti-PfRON12 antibody recognized a single band around 80 kDa under non-reducing conditions, suggesting native PfRON12 forms a disulfide-bond-mediated multimer. Immunofluorescence assay and immunoelectron microscopy revealed that PfRON12 localized to the rhoptry neck of merozoites in schizonts and to the surface of free merozoites. The biological activity of anti-PfRON12 antibody was tested by in vitro growth inhibition assay (GIA), and the rabbit antibodies significantly inhibited merozoite invasion of erythrocytes. We then investigated whether PfRON12 is immunogenic in P. falciparum-infected individuals. The sera from P. falciparum infected individuals in Thailand and Mali reacted with the recombinant PfRON12. Furthermore, human anti-PfRON12 antibodies affinity-purified from Malian serum samples inhibited merozoite invasion of erythrocytes in vitro. Moreover, pfron12 is highly conserved with only 4 non-synonymous mutations in the coding sequence from approximately 200 isolates deposited in PlasmoDB. These results suggest that PfRON12 might be a potential blood-stage vaccine candidate antigen against P. falciparum.


Assuntos
Antígenos de Protozoários/imunologia , Eritrócitos/parasitologia , Merozoítos/fisiologia , Plasmodium falciparum/imunologia , Proteínas de Protozoários/imunologia , Receptores Proteína Tirosina Quinases/imunologia , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários/genética , Infecções Assintomáticas/epidemiologia , Ensaio de Imunoadsorção Enzimática , Eritrócitos/imunologia , Imunofluorescência , Humanos , Vacinas Antimaláricas/genética , Vacinas Antimaláricas/imunologia , Malária Falciparum/epidemiologia , Malária Falciparum/imunologia , Malária Falciparum/parasitologia , Malária Falciparum/prevenção & controle , Mali/epidemiologia , Merozoítos/imunologia , Coelhos , Receptores Proteína Tirosina Quinases/genética , Proteínas Recombinantes/genética , Proteínas Recombinantes/imunologia , Esquizontes/química , Tailândia/epidemiologia
8.
PLoS Negl Trop Dis ; 12(4): e0006418, 2018 04.
Artigo em Inglês | MEDLINE | ID: mdl-29659574

RESUMO

BACKGROUND: Evidence from recent studies assessing the impact of school water, sanitation and hygiene (WASH) interventions on child health has been mixed. Self-reports of disease are subject to bias, and few WASH impact evaluations employ objective health measures to assess reductions in disease and exposure to pathogens. We utilized antibody responses from dried blood spots (DBS) to measure the impact of a school WASH intervention on infectious disease among pupils in Mali. METHODOLOGY/PRINCIPAL FINDINGS: We randomly selected 21 beneficiary primary schools and their 21 matched comparison schools participating in a matched-control trial of a comprehensive school-based WASH intervention in Mali. DBS were collected from 20 randomly selected pupils in each school (n = 807). We analyzed eluted IgG from the DBS using a Luminex multiplex bead assay to 28 antigens from 17 different pathogens. Factor analysis identified three distinct latent variables representing vector-transmitted disease (driven primarily by dengue), food/water-transmitted enteric disease (driven primarily by Escherichia coli and Vibrio cholerae), and person-to-person transmitted enteric disease (driven primarily by norovirus). Data were analyzed using a linear latent variable model. Antibody evidence of food/water-transmitted enteric disease (change in latent variable mean (ß) = -0.24; 95% CI: -0.53, -0.13) and person-to-person transmitted enteric disease (ß = -0.17; 95% CI: -0.42, -0.04) was lower among pupils attending beneficiary schools. There was no difference in antibody evidence of vector-transmitted disease (ß = 0.11; 95% CI: -0.05, 0.33). CONCLUSIONS/SIGNIFICANCE: Evidence of enteric disease was lower among pupils attending schools benefitting from school WASH improvements than students attending comparison schools. These findings support results from the parent study, which also found reduced incidence of self-reported diarrhea among pupils of beneficiary schools. DBS collection was feasible in this resource-poor field setting and provided objective evidence of disease at a low cost per antigen analyzed, making it an effective measurement tool for the WASH field. TRIAL REGISTRATION: The trial was registered at ClinicalTrials.gov (NCT01787058).


Assuntos
Anticorpos/sangue , Doenças Transmissíveis/epidemiologia , Higiene , Saneamento , Microbiologia da Água , Adolescente , Estudos de Casos e Controles , Criança , Pré-Escolar , Controle de Doenças Transmissíveis , Doenças Transmissíveis/microbiologia , Feminino , Humanos , Masculino , Mali/epidemiologia , Instituições Acadêmicas , Estudantes
9.
Rev Epidemiol Sante Publique ; 66(3): 181-185, 2018 May.
Artigo em Francês | MEDLINE | ID: mdl-29625861

RESUMO

BACKGROUND: Newborn screening for sickle cell anemia is necessary in Africa where the disease is more frequent. Hemoglobin electrophoresis is used for screening, but is limited by a high cost and difficult access. Sickling test (Emmel test), which is more affordable and technically more accessible, is often requested for prenatal assessment of pregnant women in West African areas to reserve screening for newborns from mothers in whom the positive sickling test attests the presence of hemoglobin S. This study aims to evaluate the number of undetected sickle cell anemia newborns by a screening policy targeting only newborns from mothers in whom a sickling test would have been positive. METHODS: From 2010 to 2012, in Bamako, Mali, West Africa, 2489 newborns were routinely screened for sickle cell anemia at the umbilical cord or heel by isoelectrofocusing and, if necessary, by high-performance liquid chromatography. These newborns were born from 2420 mothers whose hemoglobin was studied by isoelectrofocusing. The data was recorded and processed using Excel software version 14.0.0. We calculated the frequency of the sickle cell gene in mothers and newborns as well as the number of SCA newborns from heterozygous or C homozygous mothers. RESULTS: Of the 2489 newborns, 16 had sickle cell anemia (6 SS and 10 SC); 198 had the sickle cell trait; 139 were AC and 1 was CC. Of the 10 newborns with SC profile, 3 were born from mothers not carrying the S gene but the C gene of hemoglobin and in which an Emmel test would have been negative. CONCLUSION: Targeted newborn screening, based on the results of sickling test in pregnant women, would misdiagnose more than one of six sickle cell anemia newborns who would not benefit from early care. Cost-effectiveness studies of routine newborn screening for sickle cell anemia should lead to a better screening strategy in contexts where hemoglobin S and other hemoglobin defect genes coexist.


Assuntos
Anemia Falciforme/diagnóstico , Testes Hematológicos/métodos , Triagem Neonatal/métodos , Vigilância da População/métodos , Complicações Hematológicas na Gravidez/diagnóstico , Diagnóstico Pré-Natal , Adulto , África Ocidental/epidemiologia , Anemia Falciforme/sangue , Feminino , Testes Hematológicos/normas , Testes Hematológicos/estatística & dados numéricos , Hemoglobina Falciforme/análise , Humanos , Recém-Nascido , Limite de Detecção , Masculino , Mali/epidemiologia , Mães , Valor Preditivo dos Testes , Gravidez , Complicações Hematológicas na Gravidez/sangue , Diagnóstico Pré-Natal/métodos , Diagnóstico Pré-Natal/normas
11.
Parasit Vectors ; 11(1): 18, 2018 01 08.
Artigo em Inglês | MEDLINE | ID: mdl-29310700

RESUMO

BACKGROUND: Filariasis and leishmaniasis are two neglected tropical diseases in Mali. Due to distribution and associated clinical features, both diseases are of concern to public health. The goal of this study was to determine the prevalence of co-infection with filarial (Wuchereria bancrofti and Mansonella perstans) and Leishmania major parasites in two ecologically distinct areas of Mali, the Kolokani district (villages of Tieneguebougou and Bougoudiana) in North Sudan Savanna area, and the district of Kolondieba (village of Boundioba) in the South Sudan Savanna area. METHODS: The prevalence of co-infection (filarial and Leishmania) was measured based on (i) Mansonella perstans microfilaremia count and/or filariasis immunochromatographic test (ICT) for Wuchereria bancrofti-specific circulating antigen, and (ii) the prevalence of delayed type hypersensitivity (DTH) responses to Leishmania measured by leishmanin skin test (LST). RESULTS: In this study, a total of 930 volunteers between the age of 18 and 65 were included from the two endemic areas of Kolokani and Kolondieba. In general, in both areas, filarial infection was more prevalent than Leishmania infection with an overall prevalence of 15.27% (142/930) including 8.7% (81/930) for Mansonella perstans and 8% (74/930) for Wuchereria bancrofti-specific circulating antigen. The prevalence of Leishmania major infection was 7.7% (72/930) and was significantly higher in Tieneguebougou and Bougoudiana (15.05%; 64/425) than in Boundioba (2.04%; 8/505) (χ2 = 58.66, P < 0.0001). Among the filarial infected population, nearly 10% (14/142) were also positive for Leishmania with an overall prevalence of co-infection of 1.50% (14/930) varying from 2.82% (12/425) in Tieneguebougou and Bougoudiana to 0.39% (2/505) in Boundioba (P = 0.0048). CONCLUSION: This study established the existence of co-endemicity of filarial and Leishmania infections in specific regions of Mali. Since both filarial and Leishmania infections are vector-borne with mosquitoes and sand flies as respective vectors, an integrated vector control approach should be considered in co-endemic areas. The effect of potential interaction between filarial and Leishmania parasites on the disease outcomes may be further studied.


Assuntos
Coinfecção/epidemiologia , Doenças Endêmicas , Filariose/epidemiologia , Leishmaniose/epidemiologia , Adulto , Animais , Cromatografia de Afinidade , Estudos Transversais , Feminino , Filariose/complicações , Voluntários Saudáveis , Humanos , Leishmaniose/complicações , Masculino , Mali/epidemiologia , Microscopia , Pessoa de Meia-Idade , Prevalência , Testes Cutâneos , Sudão/epidemiologia , Adulto Jovem
12.
PLoS One ; 13(1): e0191079, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29370227

RESUMO

Malaria remains one of the leading causes of morbidity and mortality among children under five years old in many low- and middle-income countries. In this study, we examined how malaria-related ideational factors may influence care-seeking behavior among female caregivers of children under five with fever. Data came from population-based surveys conducted in 2014-2015 by U.S. Agency for International Development-funded surveys in Madagascar, Mali, and Nigeria. The outcome of interest was whether a child under five with fever within two weeks prior to the survey was brought to a formal health facility for care. Results show a wide variation in care-seeking practices for children under five with fever across countries. Seeking care for febrile children under five in the formal health sector is far from a norm in the study countries. Important ideational factors associated with care-seeking behavior included caregivers' perceived social norms regarding treatment of fever among children under five in Nigeria and Madagascar, and caregiver's knowledge of the cause of malaria in Mali. Findings indicate that messages aimed to increase malaria-related knowledge should be tailored to the specific country, and that interventions designed to influence social norms about care-seeking are likely to result in increased care-seeking behavior for fever in children under five.


Assuntos
Febre/terapia , Malária/epidemiologia , Aceitação pelo Paciente de Cuidados de Saúde , Adulto , Cuidadores , Pré-Escolar , Feminino , Febre/etiologia , Humanos , Lactente , Madagáscar/epidemiologia , Malária/complicações , Masculino , Mali/epidemiologia , Nigéria/epidemiologia
13.
Epidemiol Infect ; 146(3): 354-358, 2018 02.
Artigo em Inglês | MEDLINE | ID: mdl-29332619

RESUMO

The global spread of non-tuberculous mycobacteria (NTM) may be due to HIV/AIDS and other environmental factors. The symptoms of NTM and tuberculosis (TB) disease are indistinguishable, but their treatments are different. Lack of research on the epidemiology of NTM infections has led to underestimation of its prevalence within TB endemic countries. This study was designed to determine the prevalence and clinical characteristics of pulmonary NTM in Bamako. A cross-sectional study which include 439 suspected cases of pulmonary TB. From 2006 to 2013 a total of 332 (76%) were confirmed to have sputum culture positive for mycobacteria. The prevalence of NTM infection was 9.3% of our study population and 12.3% of culture positive patients. The seroprevalence of HIV in NTM group was 17.1%. Patients who weighed <55 kg and had TB symptoms other than cough were also significantly more likely to have disease due to NTM as compared to those with TB disease who were significantly more likely to have cough and weigh more than 55 kg (OR 0.05 (CI 0.02-0.13) and OR 0.32 (CI 0.11-0.93) respectively). NTM disease burden in Bamako was substantial and diagnostic algorithms for pulmonary disease in TB endemic countries should consider the impact of NTM.


Assuntos
Soroprevalência de HIV , Infecções por Micobactéria não Tuberculosa/epidemiologia , Infecções por Micobactéria não Tuberculosa/microbiologia , Micobactérias não Tuberculosas/isolamento & purificação , Adolescente , Adulto , Idoso , Coinfecção/epidemiologia , Estudos Transversais , Feminino , Humanos , Masculino , Mali/epidemiologia , Pessoa de Meia-Idade , Infecções por Micobactéria não Tuberculosa/diagnóstico , Prevalência , Fatores de Risco , Estudos Soroepidemiológicos , Adulto Jovem
14.
Malar J ; 17(1): 19, 2018 01 10.
Artigo em Inglês | MEDLINE | ID: mdl-29316917

RESUMO

BACKGROUND: Ségou Region in Central Mali is an area of high malaria burden with seasonal transmission, high access to and use of long-lasting insecticidal nets (LLINs), and resistance to pyrethroids and DDT well documented in Anopheles gambiae s.l. (the principal vector of malaria in Mali). Ségou has recently received indoor residual spraying (IRS) supported by Mali's collaboration with the US President's Malaria Initiative/Africa Indoor Residual Spraying programme. From 2012 to 2015, two different non-pyrethroid insecticides: bendiocarb in 2012 and 2013 and pirimiphos-methyl in 2014 and 2015, were used for IRS in two districts. This report summarizes the results of observational analyses carried out to assess the impact of these IRS campaigns on malaria incidence rates reported through local and district health systems before and after spraying. METHODS: A series of retrospective time series analyses were performed on 1,382,202 rapid diagnostic test-confirmed cases of malaria reported by district routine health systems in Ségou Region from January 2012 to January 2016. Malaria testing, treatment, surveillance and reporting activities remained consistent across districts and years during the study period, as did LLIN access and use estimates as well as An. gambiae s.l. insecticide resistance patterns. Districts were stratified by IRS implementation status and all-age monthly incidence rates were calculated and compared across strata from 2012 to 2014. In 2015 a regional but variable scale-up of seasonal malaria chemoprevention complicated the region-wide analysis; however IRS operations were suspended in Bla District that year so a difference in differences approach was used to compare 2014 to 2015 changes in malaria incidence at the health facility level in children under 5-years-old from Bla relative to changes observed in Barouéli, where IRS operations were consistent. RESULTS: During 2012-2014, rapid reductions in malaria incidence were observed during the 6 months following each IRS campaign, though most of the reduction in cases (70% of the total) was concentrated in the first 2 months after each campaign was completed. Compared to non-IRS districts, in which normal seasonal patterns of malaria incidence were observed, an estimated 286,745 total fewer cases of all-age malaria were observed in IRS districts. The total cost of IRS in Ségou was around 9.68 million USD, or roughly 33.75 USD per case averted. Further analysis suggests that the timing of the 2012-2014 IRS campaigns (spraying in July and August) was well positioned to maximize public health impact. Suspension of IRS in Bla District after the 2014 campaign resulted in a 70% increase in under-5-years-old malaria incidence rates from 2014 to 2015, significantly greater (p = 0.0003) than the change reported from Barouéli District, where incidence rates remained the same. CONCLUSIONS: From 2012 to 2015, the annual IRS campaigns in Ségou are associated with several hundred thousand fewer cases of malaria. This work supports the growing evidence that shows that IRS with non-pyrethroid insecticides is a wise public health investment in areas with documented pyrethroid resistance, high rates of LLIN coverage, and where house structures and population densities are appropriate. Additionally, this work highlights the utility of quality-assured and validated routine surveillance and well defined observational analyses to rapidly assess the impact of malaria control interventions in operational settings, helping to empower evidence-based decision making and to further grow the evidence base needed to better understand when and where to utilize new vector control tools as they become available.


Assuntos
Transmissão de Doença Infecciosa/prevenção & controle , Inseticidas/administração & dosagem , Malária/epidemiologia , Malária/prevenção & controle , Controle de Mosquitos/métodos , Compostos Organotiofosforados/administração & dosagem , Fenilcarbamatos/administração & dosagem , Adolescente , Adulto , Idoso , Animais , Criança , Pré-Escolar , Feminino , Pesquisa sobre Serviços de Saúde , Humanos , Incidência , Lactente , Recém-Nascido , Masculino , Mali/epidemiologia , Pessoa de Meia-Idade , Estudos Retrospectivos , Adulto Jovem
15.
Rev Pneumol Clin ; 74(1): 22-27, 2018 Feb.
Artigo em Francês | MEDLINE | ID: mdl-29246463

RESUMO

INTRODUCTION: Prison constitutes a risk factor for the emergence of multi-drug resistance of tuberculosis (MDR-TB). The aim of this work was to study MDR-TB in a black African carceral center. MATERIAL AND METHODS: Prospective study from January to December 2016 at the central house of arrest for men, Bamako. The study population was composed of tuberculous detainee. The suspicion of MDR-TB was done in any tuberculosis case remained positive in the second month of first-line treatment or in contact with an MDR-TB case. RESULT: Among 1622 detainee, 21 cases of pulmonary tuberculosis were notified (1.29%), with an annual incidence of 13 cases/1000 detainee, they were 16 cases of SP-PTB (microscopy smear positive tuberculosis) and five cases of microscopy smear negative tuberculosis. The mean age was 28±7 years, extremes of 18 and 46 years. A negative association was found between the notion of smoking and occupation in the occurrence of tuberculosis (OR=0.036, [95% CI: 0.03-0.04], P=0.03. Among the 21 tuberculosis cases notified, one confirmed case of MDR-TB was detected (4.7%). In the first semester of 2016 cohort, we notified a cure rate of 87.5% (7/8 SP-PTB cases), and the confirmed MDR-TB case on treatment (21-month regimen), evolution enameled of pulmonary and hearing sequelae at seven months treatment. CONCLUSION: It was the first case of MDR-TB detected in a prison in Mali. Late diagnosis, evolution is enameled of sequelae and side effects.


Assuntos
Antituberculosos/uso terapêutico , Tuberculose Resistente a Múltiplos Medicamentos/etnologia , Tuberculose Pulmonar/etnologia , Adolescente , Adulto , Afro-Americanos , Humanos , Incidência , Masculino , Mali/epidemiologia , Pessoa de Meia-Idade , Mycobacterium tuberculosis/isolamento & purificação , Prisões/estatística & dados numéricos , Estudos Prospectivos , Fatores de Risco , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Pulmonar/tratamento farmacológico , Adulto Jovem
16.
Bull Soc Pathol Exot ; 111(2): 114-120, 2018.
Artigo em Francês | MEDLINE | ID: mdl-30789237

RESUMO

This study aim was to evaluate the dynamics of Schistosoma haematobium eggs excretion after the scaling up of "Mass Drug Administration" (MDA) with praziquantel (PZQ) from 2011 to 2016 in a cohort of volunteers living in the village of Kalifabougou, Mali. We conducted a cross-sectional study on 676 volunteers in May 2011 niched in cohort study from 696 volunteers aged three months to 25 years. The eggs of Schistosoma haematobium (Sh) were tested by urine filtration technique, Soil-transmitted helminth and Schistosoma mansoni by the Kato-Katz technique. Maximal MDA/ PZQ population coverage was 83% in 2015 and no MDA/PZQ n 2014. A total of 676 volunteers was included in this prospective cohort. The prevalence rate of Sh showed a significate decreasing from 2011, 2013 to 2014 with respectively 10.2% [95% CI=10.04-10,18], 5.32% [95% CI=5.30-5.33], and 5.25% [95% CI=524.-5.31], followed by an increase to 10.6% [95% CI = 10.47-10.63] in 2015 and a significative decrease in 2016 to 5.4% [95% CI=3.5-7,3]. Children aged from six to 10 years and mostly boys were more infected with Sh, then could serve of parasite reservoir. MDA with PZQ remains an effective strategy for schistosomiasis control against Sh in Kalifabougou. Additional studies on MDA/PZQ average treatment covering human-water contact behaviors and population migration are necessary to understand the persistence of the 5% annual prevalence rate of egg shedding in the cohort of volunteers periodically treated with PQZ. Testing eggs shed viability will be also an added value.


Assuntos
Administração Massiva de Medicamentos , Contagem de Ovos de Parasitas , Praziquantel/uso terapêutico , Schistosoma haematobium/citologia , Esquistossomose Urinária/tratamento farmacológico , Adolescente , Adulto , Animais , Anti-Helmínticos/uso terapêutico , Criança , Pré-Escolar , Estudos de Coortes , Estudos Transversais , Fezes/parasitologia , Feminino , Humanos , Lactente , Estudos Longitudinais , Masculino , Mali/epidemiologia , Prevalência , Esquistossomose Urinária/epidemiologia , Esquistossomose Urinária/parasitologia , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
17.
PLoS One ; 12(12): e0189724, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29261755

RESUMO

The role of some nutrient-derived metabolites on the innate and adaptive immune responses is now established. Global research approach investigating the interplay between environment, lifestyle and the host's immune responses is crucial in the understanding of malaria susceptibility. Advanced Glycation end products (AGE), which are food-derived metabolites result from the link between reducing sugar and amino group of proteins, lipids or nucleic acids. The level of exposure to AGEs varies depending on the type of diet. The dysfunction of the immune system induced by AGE and the cellular receptors for AGEs (RAGE) in susceptibility to bacterial infection has been described. But no study has yet explored their role in susceptibility to malaria. Therefore, we aimed to evaluate systemic AGE and RAGE gene polymorphism in two sympatric populations with previously described difference of susceptibility to malaria. We measured by ELISA the plasma levels of AGEs, and their soluble receptors (sRAGE) from 170 volunteers (68 Fulani and 102 Dogon). We also determined by real-time quantitative PCR the expression of RAGE, and the -374 T/A, -429 T/C polymorphisms and 63 bp deletion by fragment length restriction polymorphism. The prevalence rate of Plasmodium in Fulani and Dogon were respectively 42.64% and 51.30% for P. falciparum, 5.88% and 6.5% for P. malariae, 0% and 2.6% for P. ovale. The average AGE was 12.65 µg/ml, and 496.48pg/ml for sRAGE. Highest levels of sRAGE were observed in Fulani (563,07pg/ml, 95% CI [547.81-580.13] vs 465.68pg/ml, 95% CI [331.19-467.51]) for Dogon, p = 0.00001. Fulani had the lowest mean of AGE (10.21µg/ml, 95% CI [8.02-10.92]) compared to Dogon (16.88µg/ml, 95% CI [13.92-17.96]; p = 0.00001. RAGE was more expressed in Dogon than Fulani (0.08 vs 0.04), P = 0.08. The -374A polymorphism vas more frequent in Fulani (32%) compared to Dogon (20%). The chronic exposure to dietary AGE could lead to immune responses impairment and polymorphism with implications in malaria susceptibility. More studies are necessary to better investigate this hypothesis.


Assuntos
Suscetibilidade a Doenças , Malária/epidemiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Ensaio de Imunoadsorção Enzimática , Feminino , Produtos Finais de Glicação Avançada/sangue , Humanos , Malária/imunologia , Malária/parasitologia , Masculino , Mali/epidemiologia , Pessoa de Meia-Idade , Plasmodium/classificação , Polimorfismo Genético , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
18.
Malar J ; 16(1): 490, 2017 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-29246158

RESUMO

BACKGROUND: Humans living in regions with high falciparum malaria transmission intensity harbour multi-strain infections comprised of several genetically distinct malaria haplotypes. The number of distinct malaria parasite haplotypes identified from an infected human host at a given time is referred to as the complexity of infection (COI). In this study, an amplicon-based deep sequencing method targeting the Plasmodium falciparum apical membrane antigen 1 (pfama1) was utilized to (1) investigate the relationship between P. falciparum prevalence and COI, (2) to explore the population genetic structure of P. falciparum parasites from malaria asymptomatic individuals participating in the 2007 Demographic and Health Survey (DHS) in the Democratic Republic of Congo (DRC), and (3) to explore selection pressures on geospatially divergent parasite populations by comparing AMA1 amino acid frequencies in the DRC and Mali. RESULTS: A total of 900 P. falciparum infections across 11 DRC provinces were examined. Deep sequencing of both individuals, for COI analysis, and pools of individuals, to examine population structure, identified 77 unique pfama1 haplotypes. The majority of individual infections (64.5%) contained polyclonal (COI > 1) malaria infections based on the presence of genetically distinct pfama1 haplotypes. A minimal correlation between COI and malaria prevalence as determined by sensitive real-time PCR was identified. Population genetic analyses revealed extensive haplotype diversity, the vast majority of which was shared across the sites. AMA1 amino acid frequencies were similar between parasite populations in the DRC and Mali. CONCLUSIONS: Amplicon-based deep sequencing is a useful tool for the detection of multi-strain infections that can aid in the understanding of antigen heterogeneity of potential malaria vaccine candidates, population genetics of malaria parasites, and factors that influence complex, polyclonal malaria infections. While AMA1 and other diverse markers under balancing selection may perform well for understanding COI, they may offer little geographic or temporal discrimination between parasite populations.


Assuntos
Variação Antigênica , Antígenos de Protozoários/genética , Malária Falciparum/epidemiologia , Proteínas de Membrana/genética , Plasmodium falciparum/genética , Proteínas de Protozoários/genética , Alelos , República Democrática do Congo/epidemiologia , Haplótipos , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Mali/epidemiologia , Prevalência
19.
Int J Mycobacteriol ; 6(4): 379-386, 2017 Oct-Dec.
Artigo em Inglês | MEDLINE | ID: mdl-29171452

RESUMO

BACKGROUND: To identify strains of Mycobacterium tuberculosis complex (MTBc) circulating in Bamako region during the past 10 years. METHODS: From 2006 to 2016, we conducted a cross-sectional study to identify with spoligotyping, clinical isolates from tuberculosis (TB)-infected patients at different stages of their treatments in Bamako, Mali. RESULTS: Among the 904 suspected TB patients included in the study and thereafter tested in our BSL-3 laboratory, 492 (54.4%) had MTBc and therefore underwent spoligotyping. Overall, three subspecies, i.e., MTB T1 (31.9%) and MTB LAM10 (15.3%) from lineage 4 and M. africanum 2 (16.8%) from lineage 6 were the leading causes of TB in Bamako region during the past 10 years. Other spoligotypes such as MTB T3, MTB Haarlem 2, MTB EAI3, and MTB family 33 were also commonly seen from 2010 to 2016. CONCLUSION: This study showed a high genetic diversity of strains isolated in Bamako region and highlights that M. tuberculosis T1 strain was the most prevalent. Furthermore, the data indicate an increasing proportion of primary drug resistance overtime in Bamako.


Assuntos
Técnicas de Tipagem Bacteriana , Mycobacterium tuberculosis/classificação , Mycobacterium tuberculosis/genética , Filogenia , Tuberculose/microbiologia , Adolescente , Adulto , Idoso , Antituberculosos/farmacologia , Antituberculosos/uso terapêutico , Criança , Pré-Escolar , Estudos Transversais , Farmacorresistência Bacteriana/efeitos dos fármacos , Feminino , Variação Genética , Genótipo , Humanos , Masculino , Mali/epidemiologia , Pessoa de Meia-Idade , Mycobacterium tuberculosis/efeitos dos fármacos , Sequências Repetitivas de Ácido Nucleico/genética , Tuberculose/tratamento farmacológico , Tuberculose/epidemiologia , Adulto Jovem
20.
Proc Natl Acad Sci U S A ; 114(47): 12566-12571, 2017 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-29114059

RESUMO

A naturally occurring Wolbachia strain (wAnga-Mali) was identified in mosquitoes of the Anopheles gambiae complex collected in the Malian villages of Dangassa and Kenieroba. Phylogenetic analysis of the nucleotide sequence of two 16S rRNA regions showed that wAnga-Mali clusters with Wolbachia strains from supergroup A and has the highest homology to a Wolbachia strain isolated from cat fleas (Ctenocephalides). wAnga-Mali is different from two Wolbachia strains previously reported in A. gambiae from Burkina Faso (wAnga_VK5_STP and wAnga_VK5_3.1a). Quantitative analysis of Wolbachia and Plasmodium sporozoite infection in field-collected mosquitoes indicates that the prevalence and intensity of Plasmodium falciparum sporozoite infection is significantly lower in Wolbachia-infected females. The presence of Wolbachia in females from a laboratory Anopheles coluzzii (A. gambiae, M form) colony experimentally infected with P. falciparum (NF54 strain) gametocyte cultures slightly enhanced oocyst infection. However, Wolbachia infection significantly reduced the prevalence and intensity of sporozoite infection, as observed in the field. This indicates that wAnga-Mali infection does not limit early stages of Plasmodium infection in the mosquito, but it has a strong deleterious effect on sporozoites and reduces malaria transmission.


Assuntos
Anopheles/microbiologia , Interações Hospedeiro-Parasita , Insetos Vetores/microbiologia , Malária Falciparum/transmissão , Plasmodium falciparum/microbiologia , Wolbachia/genética , Animais , Anopheles/parasitologia , Feminino , Interações Hospedeiro-Patógeno , Insetos Vetores/parasitologia , Malária Falciparum/epidemiologia , Malária Falciparum/parasitologia , Malária Falciparum/patologia , Mali/epidemiologia , Oocistos/patogenicidade , Oocistos/fisiologia , Filogenia , RNA Ribossômico 16S/genética , Índice de Gravidade de Doença , Esporozoítos/patogenicidade , Esporozoítos/fisiologia , Wolbachia/classificação , Wolbachia/isolamento & purificação
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