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1.
Sci Rep ; 14(1): 10926, 2024 05 13.
Artigo em Inglês | MEDLINE | ID: mdl-38740833

RESUMO

In contrast to acute diarrhoea, the aetiology of persistent digestive disorders (≥ 14 days) is poorly understood in low-resource settings and conventional diagnostic approaches lack accuracy. In this multi-country study, we compared multiplex real-time PCR for enteric bacterial, parasitic and viral pathogens in stool samples from symptomatic patients and matched asymptomatic controls in Côte d'Ivoire, Mali and Nepal. Among 1826 stool samples, the prevalence of most pathogens was highest in Mali, being up to threefold higher than in Côte d'Ivoire and up to tenfold higher than in Nepal. In all settings, the most prevalent bacteria were EAEC (13.0-39.9%) and Campylobacter spp. (3.9-35.3%). Giardia intestinalis was the predominant intestinal protozoon (2.9-20.5%), and adenovirus 40/41 was the most frequently observed viral pathogen (6.3-25.1%). Significantly different prevalences between symptomatic and asymptomatic individuals were observed for Campylobacter, EIEC and ETEC in the two African sites, and for norovirus in Nepal. Multiple species pathogen infection was common in Côte d'Ivoire and Mali, but rarely found in Nepal. We observed that molecular testing detected multiple enteric pathogens and showed low discriminatory accuracy to distinguish between symptomatic and asymptomatic individuals. Yet, multiplex PCR allowed for direct comparison between different countries and revealed considerable setting-specificity.


Assuntos
Dor Abdominal , Diarreia , Fezes , Reação em Cadeia da Polimerase Multiplex , Humanos , Côte d'Ivoire/epidemiologia , Diarreia/microbiologia , Diarreia/parasitologia , Diarreia/virologia , Diarreia/epidemiologia , Diarreia/diagnóstico , Reação em Cadeia da Polimerase Multiplex/métodos , Nepal/epidemiologia , Mali/epidemiologia , Masculino , Feminino , Adulto , Fezes/microbiologia , Fezes/parasitologia , Fezes/virologia , Adolescente , Criança , Pessoa de Meia-Idade , Pré-Escolar , Adulto Jovem , Lactente , Prevalência , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/classificação , Idoso , Giardia lamblia/isolamento & purificação , Giardia lamblia/genética
2.
BMC Infect Dis ; 21(1): 359, 2021 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-33865327

RESUMO

BACKGROUND: The epidemiology of human cysticercosis and neurocysticercosis, caused by the larval stage of the pork tapeworm Taenia solium, is not well known in the Democratic Republic of Congo (DRC). Within a multicenter etiological and diagnostic study conducted by the NIDIAG consortium ("Better Diagnosis for Neglected Infections") and investigating several challenging syndromes, we consecutively evaluated from 2012 to 2015 all patients older than 5 years presenting with neurological disorders (neurology cohort) and with fever > 7 days (persistent fever cohort) at the rural hospital of Mosango, province of Kwilu, DRC. In both cohorts, etiological diagnosis relied on a systematic set of reference laboratory assays and on pre-established clinical case definitions. No neuroimaging was available in the study hospital. In this study, we determined the frequency of T. solium infection in both cohorts and explored in the neurology cohort its association with specific neurological presentations and final etiological diagnoses. METHODS: We conducted a post-hoc descriptive and analytic study on cysticercosis in the neurology and persistent fever cohorts, based on the presence in serum samples of circulating T. solium antigen using the B158/B60 enzyme-linked immunosorbent assay (ELISA) and of cysticercosis IgG using the LDBIO Cysticercosis Western Blot IgG assay. RESULTS: For the neurology cohort, 340 samples (of 351 enrolled patients) were available for analysis (males: 46.8%; mean age: 38.9 years). T. solium antigen positivity was found in 43 participants (12.6%; 95% confidence interval [CI] 9.3-16.7%), including 9 of 60 (15%) patients with epilepsy. Among the 148 samples available from the persistent fever cohort (males: 39.9%; mean age: 19.9 years), 7 were positive in the T. solium antigen ELISA (4.7%; 95% CI 1.9-9.5%; P = 0.009 when compared to the neurology cohort). No significant association was found within the neurology cohort between positivity and clinical presentation or final diagnoses. Of note, the IgG antibody-detecting assay was found positive in only four (1.3%) of the participants of the neurology cohort and in none of the persistent fever cohort. CONCLUSIONS: T. solium antigen positivity was found in at least 10% of patients admitted with neurological disorders in the Kwilu province, DRC, with no specific pattern of presentation. Further neuroimaging studies should be used to confirm whether neurocysticercosis is prevalent in this region.


Assuntos
Antígenos de Helmintos/sangue , Doenças do Sistema Nervoso/epidemiologia , Neurocisticercose/epidemiologia , Taenia solium/imunologia , Adolescente , Adulto , Idoso , Animais , Criança , Estudos de Coortes , República Democrática do Congo/epidemiologia , Ensaio de Imunoadsorção Enzimática , Epilepsia/diagnóstico , Epilepsia/epidemiologia , Epilepsia/parasitologia , Feminino , Hospitais Rurais/estatística & dados numéricos , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/parasitologia , Neurocisticercose/sangue , Neurocisticercose/diagnóstico , Admissão do Paciente/estatística & dados numéricos , Estudos Soroepidemiológicos , Teníase/sangue , Teníase/diagnóstico , Teníase/epidemiologia , Adulto Jovem
3.
PLoS Negl Trop Dis ; 14(12): e0008832, 2020 12.
Artigo em Inglês | MEDLINE | ID: mdl-33315896

RESUMO

BACKGROUND: Human African trypanosomiases caused by the Trypanosoma brucei gambiense parasite is a lethal disease targeted for eradication. One of the main disease control strategies is active case-finding through outreach campaigns. In 2014, a new method for active screening was developed with mini, motorcycle-based, teams. This study compares the cost of two active case-finding approaches, namely the traditional mobile teams and mini mobile teams, in the two health districts of the Democratic Republic of the Congo. METHODS: The financial and economic costs of both approaches were estimated from a health care provider perspective. Cost and operational data were collected for 12 months for 1 traditional team and 3 mini teams. The cost per person screened and diagnosed was calculated and univariate sensitivity analysis was conducted to identify the main cost drivers. RESULTS: During the study period in total 264,630 people were screened, and 23 HAT cases detected. The cost per person screened was lower for a mini team than for a traditional team in the study setting (US$1.86 versus US$2.08). A comparable result was found in a scenario analysis, assuming both teams would operate in a similar setting, with the cost per person screened by a mini team 15% lower than the cost per person screened by a traditional team (1.86 $ vs 2.14$). The main explanations for this lower cost are that mini teams work with fewer human resources, cheaper means of transportation and do not perform the Capillary Tube Centrifugation test or card agglutination test dilutions. DISCUSSION: Active HAT screening with mini mobile teams has a lower cost and could be a cost-effective alternative for active case-finding. Further research is needed to determine if mini mobile teams have similar or better yields than traditional mobile teams in terms of detections and cases successfully treated.


Assuntos
Atenção à Saúde/métodos , Programas de Rastreamento/economia , Programas de Rastreamento/métodos , Tripanossomíase Africana/diagnóstico , Tripanossomíase Africana/epidemiologia , Testes de Aglutinação , Atenção à Saúde/economia , República Democrática do Congo/epidemiologia , Custos de Cuidados de Saúde , Humanos , Sensibilidade e Especificidade , Trypanosoma brucei gambiense
4.
Sci Rep ; 9(1): 15505, 2019 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-31664120

RESUMO

In low-resource hospitals of central Africa, neurological disorders are frequent and etiologies very diverse. The difficulty to identify invasive bacterial infections in this setting results in major antibiotic overuse. Biomarkers such as C-reactive protein (CRP) and procalcitonin (PCT) may help discriminate these conditions. We retrospectively determined the concentrations of CRP and PCT in the sera of patients consecutively enrolled from 2012 to 2015 in an etiological study on neurological disorders at the rural hospital of Mosango, Democratic Republic of Congo. Invasive bacterial infection had been diagnosed by the demonstration of a bacterial pathogen in cerebrospinal fluid or blood cultures or the presence of radiological pneumonia. Sera of 313 (89.2%) and 317 (90.3%) of the 351 enrolled participants were available for determination of CRP and PCT concentrations respectively. Areas under the receiver operating characteristic curves for invasive bacterial infection, diagnosed in 19 tested cases, were 94.3% for CRP and 91.7% for PCT. No single case had a normal CRP concentration (<10 mg/L). Our data, although limited, suggest that CRP or PCT concentrations may help discriminate invasive bacterial infections in patients with neurological disorders in tropical settings and that normal CRP values could assist in withholding antibiotics.


Assuntos
Proteína C-Reativa/metabolismo , Doenças do Sistema Nervoso/sangue , Pró-Calcitonina/sangue , População Rural , Adulto , Biomarcadores/sangue , República Democrática do Congo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Curva ROC , Estudos Retrospectivos
5.
BMC Public Health ; 19(1): 118, 2019 Jan 28.
Artigo em Inglês | MEDLINE | ID: mdl-30691432

RESUMO

BACKGROUND: Cystic echinococcosis (CE), a neglected zoonosis caused by the larval stage of the tapeworm Echinococcus granulosus, remains a public health issue in many developing countries that practice extensive sheep breeding. Control of CE is difficult and requires a community-based integrated approach. We assessed the communities' knowledge and perception of CE, its animal hosts, and its control in a CE endemic area of the High Atlas Mountains, Morocco. METHODS: We conducted twenty focus group discussions (FGDs) stratified by gender with villagers, butchers and students in ten Berber villages that were purposefully selected for their CE prevalence. RESULTS: This community considers CE to be a severe and relatively common disease in humans and animals but has a poor understanding of the parasite's life cycle. Risk behaviour and disabling factors for disease control are mainly related to cultural practices in sheep breeding and home slaughtering, dog keeping, and offal disposal at home, as well as in slaughterhouses. Participants in our focus group discussions were supportive of control measures as management of canine populations, waste disposal, and monitoring of slaughterhouses. CONCLUSIONS: The uncontrolled stray dog population and dogs having access to offal (both at village dumps and slaughterhouses) suggest that authorities should be more closely involved in CE control. This study also highlights the need for improved knowledge about the transmission cycle of the parasite among communities and health professionals. Inter-sectoral collaboration between health staff, veterinarians, and social scientists appears to be crucial for sustainable control of this parasitic zoonosis.


Assuntos
Equinococose/prevenção & controle , Conhecimentos, Atitudes e Prática em Saúde , Doenças Negligenciadas/prevenção & controle , Zoonoses/prevenção & controle , Animais , Cães , Equinococose/epidemiologia , Feminino , Grupos Focais , Humanos , Masculino , Marrocos/epidemiologia , Doenças Negligenciadas/epidemiologia , Prevalência , Ovinos , Zoonoses/epidemiologia
6.
BMJ Glob Health ; 3(3): e000709, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29736277

RESUMO

Miltefosine, the only oral drug approved for the treatment of leishmaniasis-a parasitic disease transmitted by sandflies-is considered as a success story of research and development (R&D) by a public-private partnership (PPP). It epitomises the multiple market failures faced by a neglected disease drug: patients with low ability to pay, neglect by authorities and uncertain market size. Originally developed as an anticancer agent in the 1990s, the drug was registered in India in 2002 to treat the fatal visceral leishmaniasis. At the time, miltefosine was considered a breakthrough in the treatment, making it feasible to eliminate a regional disease. Today, access to miltefosine remains far from secure. The initial PPP agreement which includes access to the public sector is not enforced. The reality on the ground has been challenging: shortages due to inefficient supply chains, and use of a substandard product which led to a high number of treatment failures and deaths. Miltefosine received orphan drug status in the USA; when it was registered there in 2014, a priority review voucher (PRV) was awarded. The PRV, meant to facilitate drug development for neglected disease, was subsequently sold to another company for US$125 million without, to date, any apparent impact on drug access. At the heart of these concerns are questions on how to protect societal benefit of a drug developed with public investment, while clinicians worldwide struggle with its lack of affordability, limited availability and sustainability of access. This article analyses the reasons behind the postregistration access failure of miltefosine and provides the lessons learnt.

7.
Clin Infect Dis ; 67(6): 827-834, 2018 08 31.
Artigo em Inglês | MEDLINE | ID: mdl-29538642

RESUMO

Background: The diagnosis of the neglected tropical skin and soft tissue disease Buruli ulcer (BU) is made on clinical and epidemiological grounds, after which treatment with BU-specific antibiotics is initiated empirically. Given the current decline in BU incidence, clinical expertise in the recognition of BU is likely to wane and laboratory confirmation of BU becomes increasingly important. We therefore aimed to determine the diagnostic accuracy of clinical signs and microbiological tests in patients presenting with lesions clinically compatible with BU. Methods: A total of 227 consecutive patients were recruited in southern Benin and evaluated by clinical diagnosis, direct smear examination (DSE), polymerase chain reaction (PCR), culture, and histopathology. In the absence of a gold standard, the final diagnosis in each patient was made using an expert panel approach. We estimated the accuracy of each test in comparison to the final diagnosis and evaluated the performance of 3 diagnostic algorithms. Results: Among the 205 patients with complete data, the attending clinicians recognized BU with a sensitivity of 92% (95% confidence interval [CI], 85%-96%), which was higher than the sensitivity of any of the laboratory tests. However, 14% (95% CI, 7%-24%) of patients not suspected to have BU at diagnosis were classified as BU by the expert panel. The specificities of all diagnostics were high (≥91%). All diagnostic algorithms had similar performances. Conclusions: A broader clinical suspicion should be recommended to reduce missed BU diagnoses. Taking into consideration diagnostic accuracy, time to results, cost-effectiveness, and clinical generalizability, a stepwise diagnostic approach reserving PCR to DSE-negative patients performed best.


Assuntos
Úlcera de Buruli/diagnóstico , Doenças Negligenciadas/diagnóstico , Pele/patologia , Adolescente , Adulto , Algoritmos , Benin/epidemiologia , Biópsia , Úlcera de Buruli/epidemiologia , Criança , Doenças Endêmicas , Feminino , Humanos , Masculino , Microscopia/normas , Mycobacterium ulcerans/genética , Mycobacterium ulcerans/isolamento & purificação , Doenças Negligenciadas/epidemiologia , Doenças Negligenciadas/microbiologia , Reação em Cadeia da Polimerase/normas , Sensibilidade e Especificidade , Pele/microbiologia , Adulto Jovem
8.
PLoS Negl Trop Dis ; 9(5): e0003738, 2015 May.
Artigo em Inglês | MEDLINE | ID: mdl-25965564

RESUMO

BACKGROUND: Diagnostic guidelines for Visceral Leishmaniasis (VL) in the East African region are complex. Patients meeting the VL clinical case definition should be tested by rK39 rapid diagnostic test (RDT) followed by the Direct Agglutination Test (DAT) or tissue aspiration if RDT-negative. Otherwise, RDT-positive patients should be started on VL treatment. We evaluated how this guideline is adhered to by assessing the routine clinical practice in a university hospital in North-West Ethiopia. METHODS: Retrospective record analysis was done for all patients who had an rK39-RDT done at University of Gondar (UoG) Hospital between June 2012 and June 2013. We described the diagnostic work-up performed and the proportion initiated on VL treatment by test result. RESULTS/FINDINGS: From a total of 928 patients tested, 308 (33.2%) were rK39 RDT-positive. Spleen or bone marrow aspiration was done for 237 (77.2%) RDT-positive patients. Of these, 165 were confirmed parasitologically, yielding a positive predictive value of 69.6%. Only 126 (20.3%) of the 620 patients with a negative rK39 test underwent further testing by tissue aspiration, of which 22 (17.5%) were also parasitology positive. HIV test results were available for 570 (61.4%) patients and 36 (6.3%) were HIV-infected. Of the 187 parasitologically confirmed patients, 182 (97.3%) were started on VL treatment. CONCLUSIONS/DISCUSSION: A negative rK39 test was often not followed by further testing and a positive rK39 test result was followed by tissue aspiration in three out of four cases. Further research is required to understand why the diagnostic work-up did not comply with the guidelines, including evaluating adherence to the VL clinical case definition and quality of rK39-RDT testing.


Assuntos
Antígenos de Protozoários/imunologia , Testes Diagnósticos de Rotina/métodos , Fidelidade a Diretrizes , Leishmaniose Visceral/diagnóstico , Proteínas de Protozoários/imunologia , Adulto , Testes de Aglutinação/métodos , Medula Óssea/imunologia , Etiópia , Feminino , Infecções por HIV/diagnóstico , Infecções por HIV/imunologia , Hospitais , Humanos , Masculino , Guias de Prática Clínica como Assunto , Estudos Retrospectivos , Sensibilidade e Especificidade , Baço/imunologia , Adulto Jovem
9.
Lancet Glob Health ; 2(6): e359-63, 2014 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-25103304

RESUMO

BACKGROUND: Human African trypanosomiasis (HAT) is a life-threatening infection affecting rural populations in sub-Saharan Africa. Large-scale population screening by antibody detection with the Card Agglutination Test for Trypanosomiasis (CATT)/Trypanosoma brucei (T b) gambiense helped reduce the number of reported cases of gambiense HAT to fewer than 10 000 in 2011. Because low case numbers lead to decreased cost-effectiveness of such active screening, we aimed to assess diagnostic accuracy of a rapid serodiagnostic test (HAT Sero-K-SeT) applicable in primary health-care centres. METHODS: In our case-control study, we assessed participants older than 11 years who presented for HAT Sero-K-SeT and CATT/T b gambiense at primary care centres or to mobile teams (and existing patients with confirmed disease status at these centres) in Bandundu Province, DR Congo. We defined cases as patients with trypanosomes that had been identified in lymph node aspirate, blood, or cerebrospinal fluid. During screening, we recruited controls without previous history of HAT or detectable trypanosomes in blood or lymph who resided in the same area as the cases. We assessed diagnostic accuracy of three antibody detection tests for gambiense HAT: HAT Sero-K-SeT and CATT/T b gambiense (done with venous blood at the primary care centres) and immune trypanolysis (done with plasma at the Institute of Tropical Medicine, Antwerp, Belgium). FINDINGS: Between June 6, 2012, and Feb 25, 2013, we included 134 cases and 356 controls. HAT Sero-K-SeT had a sensitivity of 0·985 (132 true positives, 95% CI 0·947-0·996) and a specificity of 0·986 (351 true negatives, 0·968-0·994), which did not differ significantly from CATT/T b gambiense (sensitivity 95% CI 0·955, 95% CI 0·906-0·979 [128 true positives] and specificity 0·972, 0·949-0·985 [346 true negatives]) or immune trypanolysis (sensitivity 0·985, 0·947-0·996 [132 true positives] and specificity 0·980, 0·960-0·990 [349 true negatives]). INTERPRETATION: The diagnostic accuracy of HAT Sero-K-SeT is adequate for T b gambiense antibody detection in local health centres and could be used for active screening whenever a cold chain and electricity supply are unavailable and CATT/T b gambiense cannot be done.


Assuntos
Testes Diagnósticos de Rotina/métodos , Testes Sorológicos/métodos , Trypanosoma brucei gambiense/imunologia , Tripanossomíase Africana/sangue , Adulto , Testes de Aglutinação/normas , Animais , Anticorpos Antiprotozoários/sangue , Estudos de Casos e Controles , Testes Diagnósticos de Rotina/normas , Feminino , Gâmbia , Testes de Hemaglutinação/métodos , Humanos , Masculino , Programas de Rastreamento/métodos , Pessoa de Meia-Idade , Sensibilidade e Especificidade , Testes Sorológicos/normas , Adulto Jovem
10.
Lancet Infect Dis ; 13(6): 546-58, 2013 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-23623369

RESUMO

Infections are a leading cause of life-threatening neuropathology worldwide. In central African countries affected by endemic diseases such as human African trypanosomiasis, tuberculosis, HIV/AIDS, and schistosomiasis, delayed diagnosis and treatment often lead to avoidable death or severe sequelae. Confirmatory microbiological and parasitological tests are essential because clinical features of most neurological infections are not specific, brain imaging is seldom feasible, and treatment regimens are often prolonged or toxic. Recognition of this diagnostic bottleneck has yielded major investment in application of advances in biotechnology to clinical microbiology in the past decade. We review the neurological pathogens for which rapid diagnostic tests are most urgently needed in central Africa, detail the state of development of putative rapid diagnostic tests for each, and describe key technical and operational challenges to their development and implementation. Promising field-suitable rapid diagnostic tests exist for the diagnosis of human African trypanosomiasis and cryptococcal meningoencephalitis. For other infections-eg, syphilis and schistosomiasis-highly accurate field-validated rapid diagnostic tests are available, but their role in diagnosis of disease with neurological involvement is still unclear. For others-eg, tuberculosis-advances in research have not yet yielded validated tests for diagnosis of neurological disease.


Assuntos
Técnicas de Diagnóstico Neurológico , Infecções/diagnóstico , Doenças do Sistema Nervoso/diagnóstico , África Central , Humanos , Meningite Criptocócica/diagnóstico , Doenças do Sistema Nervoso/microbiologia , Doenças do Sistema Nervoso/parasitologia , Tripanossomíase Africana/diagnóstico
11.
Comp Immunol Microbiol Infect Dis ; 36(3): 233-9, 2013 May.
Artigo em Inglês | MEDLINE | ID: mdl-23260374

RESUMO

BACKGROUND: Neglected zoonoses continue to significantly affect human health in low-resource countries. A symposium was organised in Antwerp, Belgium, on 5 November 2010 to evaluate how intersectoral collaboration among educational and research institutions could improve the situation. RESULTS: Brucellosis and echinococcosis were presented as models for intersectoral collaboration. Low-resource societies face evident knowledge gaps on disease distribution, transmission within and across species and impact on human and animal health, precluding the development of integrated control strategies. RECOMMENDATIONS: While veterinarians have been the main driver of the One Health initiative, the medical profession does not seem to be fully aware of how veterinary science can contribute to human public health. It was postulated that transdisciplinarity could help fill knowledge gaps and that encouraging such transdisciplinarity should start with undergraduate students. Furthermore, intersectoral collaboration on zoonoses should not ignore the social sciences (e.g. assessment of indigenous knowledge and perception; participatory surveillance), which can contribute to a better understanding of the transmission of diseases and improve communities' participation in disease control activities.


Assuntos
Brucelose/transmissão , Comportamento Cooperativo , Equinococose/transmissão , Zoonoses/epidemiologia , Zoonoses/transmissão , Animais , Brucelose/prevenção & controle , Países em Desenvolvimento , Equinococose/prevenção & controle , Humanos , Médicos , Saúde Pública , Médicos Veterinários
12.
Clin Vaccine Immunol ; 19(6): 961-6, 2012 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-22539471

RESUMO

Depressed cell-mediated immunity in human visceral leishmaniasis (VL) (also known as kala-azar), revealed as the inability of peripheral blood mononuclear cells (PBMCs) to respond to Leishmania antigen, remains a hallmark of and is thought to underlie the progressive nature of this disease. We recently reported the ability of a whole-blood, gamma interferon (IFN-γ) release assay to detect subclinical infections among healthy individuals living in an area where kala-azar is endemic (Bihar, India) and the surprising result that patients with active VL also secreted significant levels of antigen-specific IFN-γ in this assay. We were interested in ascertaining whether these findings would be true for a larger cohort of subjects and in employing the whole-blood assay to detect additional cytokines that might better correlate with the disease status of infected individuals. We evaluated IFN-γ, tumor necrosis factor alpha (TNF-α), and interleukin-10 (IL-10) release in 35 patients with active VL, 54 patients with VL who were cured, 27 patients with other diseases, 52 healthy controls who lived in regions where VL or kala-azar is not endemic (NEHCs [for nonendemic healthy controls]), and 147 healthy controls who lived in regions where kala-azar is endemic (EHCs [for endemic healthy controls]). The cellular responses of the EHCs were correlated with their serological antibody titers against Leishmania donovani and Phlebotomus argentipes saliva. The whole-blood cells from the majority of both active (80%) and cured (85%) VL patients, as well as 24% of EHCs with presumed subclinical infections, produced significantly elevated levels of IFN-γ. The findings do not support a severe Th1 response defect in kala-azar. Importantly, only the patients with active VL also produced IL-10, which in conjunction with IFN-γ better reflects the immune responses that distinguish individuals with active disease from cured or subclinically infected, immune individuals.


Assuntos
Biomarcadores/análise , Interferon gama/metabolismo , Interleucina-10/metabolismo , Leishmania donovani/imunologia , Leishmaniose Visceral/imunologia , Leucócitos Mononucleares/imunologia , Fator de Necrose Tumoral alfa/metabolismo , Adolescente , Adulto , Animais , Anticorpos Antiprotozoários/sangue , Criança , Feminino , Humanos , Índia , Masculino , Phlebotomus/imunologia , Adulto Jovem
13.
Am J Trop Med Hyg ; 85(6): 1100-5, 2011 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-22144452

RESUMO

We report our experience in managing 13 consecutive clinically suspected cases of Buruli ulcer on the face treated at the hospital of the Institut Médical Evangélique at Kimpese, Democratic Republic of Congo diagnosed during 2003-2007. During specific antibiotherapy, facial edema diminished, thus minimizing the subsequent extent of surgery and severe disfigurations. The following complications were observed: 1) lagophthalmos from scarring in four patients and associated ectropion in three of them; 2) blindness in one eye in one patient; 3) disfiguring exposure of teeth and gums resulting from excision of the left labial commissure that affected speech, drinking, and eating in one patient; and 4) dissemination of Mycobacterium ulcerans infection in three patients. Our study highlights the importance of this clinical presentation of Buruli ulcer, and the need for health workers in disease-endemic areas to be aware of the special challenges management of Buruli ulcer on the face presents.


Assuntos
Úlcera de Buruli/diagnóstico , Mycobacterium ulcerans , Adolescente , Idoso , Cegueira/etiologia , Cegueira/microbiologia , Úlcera de Buruli/complicações , Úlcera de Buruli/patologia , Criança , Pré-Escolar , República Democrática do Congo/epidemiologia , Edema/etiologia , Edema/microbiologia , Face/microbiologia , Face/patologia , Feminino , Humanos , Masculino
14.
PLoS Negl Trop Dis ; 5(4): e1042, 2011 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-21526219

RESUMO

BACKGROUND: In areas endemic for visceral leishmaniasis (VL), a large number of infected individuals mount a protective cellular immune response and remain asymptomatic carriers. We propose an interferon-gamma release assay (IFN-γRA) as a novel marker for latent L. donovani infection. METHODS AND FINDINGS: We modified a commercial kit (QuantiFERON) evaluating five different leishmania-specific antigens; H2B, H2B-PSA2, H2B-Lepp12, crude soluble antigen (CSA) and soluble leishmania antigen (SLA) from L. donovani with the aim to detect the cell-mediated immune response in VL. We evaluated the assay on venous blood samples of active VL patients (n = 13), cured VL patients (n = 15), non-endemic healthy controls (n = 11) and healthy endemic controls (n = 19). The assay based on SLA had a sensitivity of 80% (95% CI = 54.81-92.95) and specificity of 100% (95% CI = 74.12-100). CONCLUSION: Our findings suggest that a whole-blood SLA-based QuantiFERON assay can be used to measure the cell-mediated immune response in L. donovani infection. The positive IFN-γ response to stimulation with leishmania antigen in patients with active VL was contradictory to the conventional finding of a non-proliferative antigen-specific response of peripheral blood mononuclear cells and needs further research.


Assuntos
Técnicas de Laboratório Clínico/métodos , Interferon gama/metabolismo , Leishmania donovani/imunologia , Leishmaniose Visceral/diagnóstico , Antígenos de Protozoários , Sangue/imunologia , Humanos , Imunidade Celular , Imunoensaio/métodos , Leucócitos Mononucleares/imunologia , Sensibilidade e Especificidade
15.
PLoS Negl Trop Dis ; 4(8): e798, 2010 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-20808908

RESUMO

BACKGROUND: Recently, a number of Global Health Initiatives (GHI) have been created to address single disease issues in low-income countries, such as poliomyelitis, trachoma, neonatal tetanus, etc.. Empirical evidence on the effects of such GHIs on local health systems remains scarce. This paper explores positive and negative effects of the Integrated Neglected Tropical Disease (NTD) Control Initiative, consisting in mass preventive chemotherapy for five targeted NTDs, on Mali's health system where it was first implemented in 2007. METHODS AND FINDINGS: Campaign processes and interactions with the health system were assessed through participant observation in two rural districts (8 health centres each). Information was complemented by interviews with key informants, website search and literature review. Preliminary results were validated during feedback sessions with Malian authorities from national, regional and district levels. We present positive and negative effects of the NTD campaign on the health system using the WHO framework of analysis based on six interrelated elements: health service delivery, health workforce, health information system, drug procurement system, financing and governance. At point of delivery, campaign-related workload severely interfered with routine care delivery which was cut down or totally interrupted during the campaign, as nurses were absent from their health centre for campaign-related activities. Only 2 of the 16 health centres, characterized by a qualified, stable and motivated workforce, were able to keep routine services running and to use the campaign as an opportunity for quality improvement. Increased workload was compensated by allowances, which significantly improved staff income, but also contributed to divert attention away from core routine activities. While the campaign increased the availability of NTD drugs at country level, parallel systems for drug supply and evaluation requested extra efforts burdening local health systems. The campaign budget barely financed institutional strengthening. Finally, though the initiative rested at least partially on national structures, pressures to absorb donated drugs and reach short-term coverage results contributed to distract energies away from other priorities, including overall health systems strengthening. CONCLUSIONS: Our study indicates that positive synergies between disease specific interventions and nontargeted health services are more likely to occur in robust health services and systems. Disease-specific interventions implemented as parallel activities in fragile health services may further weaken their responsiveness to community needs, especially when several GHIs operate simultaneously. Health system strengthening will not result from the sum of selective global interventions but requires a comprehensive approach.


Assuntos
Antiparasitários/uso terapêutico , Quimioprevenção/métodos , Atenção à Saúde/estatística & dados numéricos , Serviços de Saúde/estatística & dados numéricos , Doenças Parasitárias/epidemiologia , Doenças Parasitárias/prevenção & controle , Avaliação de Programas e Projetos de Saúde , Países em Desenvolvimento , Humanos , Mali/epidemiologia
16.
PLoS Negl Trop Dis ; 4(7): e736, 2010 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-20625556

RESUMO

BACKGROUND: The World Health Organization (WHO) advises treatment of Mycobacterium ulcerans disease, also called "Buruli ulcer" (BU), with a combination of the antibiotics rifampicin and streptomycin (R+S), whether followed by surgery or not. In endemic areas, a clinical case definition is recommended. We evaluated the effectiveness of this strategy in a series of patients with large ulcers of > or =10 cm in longest diameter in a rural health zone of the Democratic Republic of Congo (DRC). METHODS: A cohort of 92 patients with large ulcerated lesions suspected to be BU was enrolled between October 2006 and September 2007 and treated according to WHO recommendations. The following microbiologic data were obtained: Ziehl-Neelsen (ZN) stained smear, culture and PCR. Histopathology was performed on a sub-sample. Directly observed treatment with R+S was administered daily for 12 weeks and surgery was performed after 4 weeks. Patients were followed up for two years after treatment. FINDINGS: Out of 92 treated patients, 61 tested positive for M. ulcerans by PCR. PCR negative patients had better clinical improvement than PCR positive patients after 4 weeks of antibiotics (54.8% versus 14.8%). For PCR positive patients, the outcome after 4 weeks of antibiotic treatment was related to the ZN positivity at the start. Deterioration of the ulcers was observed in 87.8% (36/41) of the ZN positive and in 12.2% (5/41) of the ZN negative patients. Deterioration due to paradoxical reaction seemed unlikely. After surgery and an additional 8 weeks of antibiotics, 98.4% of PCR positive patients and 83.3% of PCR negative patients were considered cured. The overall recurrence rate was very low (1.1%). INTERPRETATION: Positive predictive value of the WHO clinical case definition was low. Low relapse rate confirms the efficacy of antibiotics. However, the need for and the best time for surgery for large Buruli ulcers requires clarification. We recommend confirmation by ZN stain at the rural health centers, since surgical intervention without delay may be necessary on the ZN positive cases to avoid progression of the disease. PCR negative patients were most likely not BU cases. Correct diagnosis and specific management of these non-BU ulcers cases are urgently needed.


Assuntos
Antibacterianos/uso terapêutico , Úlcera de Buruli/diagnóstico , Úlcera de Buruli/tratamento farmacológico , Mycobacterium ulcerans/isolamento & purificação , Rifampina/uso terapêutico , Estreptomicina/uso terapêutico , Adolescente , Adulto , Idoso , Técnicas Bacteriológicas , Úlcera de Buruli/microbiologia , Criança , Pré-Escolar , Estudos de Coortes , República Democrática do Congo , Feminino , Histocitoquímica , Humanos , Masculino , Pessoa de Meia-Idade , Mycobacterium ulcerans/citologia , Mycobacterium ulcerans/genética , Mycobacterium ulcerans/crescimento & desenvolvimento , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
17.
Mem. Inst. Oswaldo Cruz ; 104(8): 1183-1186, Dec. 2009. tab
Artigo em Inglês | LILACS | ID: lil-538181

RESUMO

Observational studies in the Indian subcontinent have shown that untreated nets may be protective against visceral leishmaniasis (VL). In this study, we evaluated the effect of untreated nets on the blood feeding rates of Phlebotomus argentipes as well as the human blood index (HBI) in VL endemic villages in India and Nepal. The study had a "before and after intervention" design in 58 households in six clusters. The use of untreated nets reduced the blood feeding rate by 85 percent (95 percent CI 76.5-91.1 percent) and the HBI by 42.2 percent (95 percent CI 11.1-62.5 percent). These results provide circumstantial evidence that untreated nets may provide some degree of personal protection against sand fly bites.


Assuntos
Animais , Feminino , Masculino , Mordeduras e Picadas/prevenção & controle , Comportamento Alimentar/fisiologia , Controle de Insetos/instrumentação , Insetos Vetores/fisiologia , Phlebotomus/fisiologia , Índia/epidemiologia , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/prevenção & controle , Leishmaniose Visceral/transmissão , Nepal/epidemiologia
18.
Trop Med Int Health ; 14(4): 404-11, 2009 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-19228350

RESUMO

OBJECTIVE: To compare a PCR assay and direct agglutination test (DAT) for the detection of potential markers of Leishmania infection in 231 healthy subjects living in a kala-azar endemic focus of Nepal. METHODS: The sample was composed of 184 (80%) persons without any known history of KA and not living in the same house as known kala-azar cases (HNK), 24 (10%) Healthy Household Contacts (HHC) and 23 (10%) past kala-azar cases which had been successfully treated (HPK). RESULTS: PCR and DAT positivity scores were, respectively: HNK, 17.6% and 5.6%; HHC, 12.5% and 20.8%; HPK, 26.1% and 95.7%. The ratio PCR-positives/DAT-positives was significantly higher in HNK (ratio = 3.1) than in HHC (ratio = 0.6, P = 0.036) and in HPK (ratio = 0.2, P = 0.012). The ratio PCR-positives/DAT-positives did not significantly differ between HHC (ratio = 0.6) and HPK (ratio = 0.2, P = 0.473). The positive agreement index between PCR and DAT in HNK was 5%; in HHC, 0%; in HPK, 43%. CONCLUSIONS: Our study highlights the specific character of PCR and DAT for the exploration of Leishmania asymptomatic infections. PCR is probably more informative for very recent infections among HNK, while DAT provides more information among HHC and HPK, a feature likely related to the power of serology to track less recent infections.


Assuntos
Leishmaniose Visceral/diagnóstico , Leishmaniose Visceral/epidemiologia , Testes de Aglutinação/métodos , Animais , Anticorpos Antiprotozoários/sangue , Antígenos de Protozoários , Biomarcadores/sangue , DNA de Protozoário/sangue , Humanos , Leishmania donovani/isolamento & purificação , Programas de Rastreamento/métodos , Nepal , Reação em Cadeia da Polimerase/métodos
19.
Infect Immun ; 77(5): 2022-9, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19237520

RESUMO

The mechanisms linking the immune response to cutaneous and mucosal leishmaniasis (CL and ML, respectively) lesions and the response to treatment are incompletely understood. Our aims were to prospectively assess, by quantitative reverse transcription-PCR, the levels of mRNA for gamma interferon, tumor necrosis factor alpha, interleukin-10 (IL-10), IL-4, and IL-13, as well as the presence of T cells (CD2) and macrophages (CD68), in CL and ML lesions and to follow their changes in response to treatment with pentavalent antimonials. The leishmanin skin test (LST) was performed on all CL and ML patients before treatment. The patient population included individuals living in areas of Peru where the disease is endemic, i.e., 129 with CL and 43 with ML. Compared to CL patients, the LST induration size was larger, the levels of all cytokine mRNAs but IL-10 were higher, T-cell mRNA was similar, and macrophage mRNA was lower in ML patients. The proportion of CL patients with an LST induration size of >8 mm was higher among responders to treatment. In CL, the pretreatment levels of cytokine mRNAs did not discriminate between responders and nonresponders; however, treatment was more often accompanied by a reduction in the levels of T-cell and cytokine mRNAs in responders than in nonresponders. Furthermore, the production of cytokines per T cell and macrophage decreased with treatment but IL-10 production remained high in nonresponders. Overall, these findings point to complex relationships among New World Leishmania parasites, skin and mucosal immune responses, and treatment outcome. The persistence of high levels of IL-10 in CL is characteristically associated with a poor response to treatment.


Assuntos
Antimônio/uso terapêutico , Antiprotozoários/uso terapêutico , Citocinas/biossíntese , Leishmaniose Cutânea/tratamento farmacológico , Leishmaniose Cutânea/imunologia , Macrófagos/imunologia , Linfócitos T/imunologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Animais , Criança , Pré-Escolar , Feminino , Perfilação da Expressão Gênica , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Peru , Estudos Prospectivos , Pele/patologia , Resultado do Tratamento , Adulto Jovem
20.
PLoS Negl Trop Dis ; 3(1): e355, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19159009

RESUMO

OBJECTIVE: We sought to estimate visceral leishmaniasis (VL) burden in Bangladesh, India, and Nepal and document care-seeking behaviour for VL to provide baseline information for monitoring the VL elimination program and identify options for improved case finding and management. DESIGN: A cross-sectional study using cluster sampling (clusters being villages) of 4 VL endemic districts was used in order to document all current and existing VL cases over the preceding 12 mo. Extended (in-depth) interviews were conducted in a subsample of households to explore (a) VL-related knowledge, attitudes, and practices of the population; (b) use of VL care by patients; and (c) delay between onset of symptoms, diagnosis, and start of treatment, as well as treatment interruption. Findings were discussed with national program managers and policy makers to develop improved strategies. RESULTS: Screening for VL was done in 18,933 households (106,425 inhabitants). The estimated annual incidence of VL in the endemic districts was on average 22 times higher than the elimination target of less than one case per 10,000 inhabitants in 2015. This incidence varied widely between study sites, from 9.0 to 29.8 per 10,000 inhabitants. The percentage of newly detected cases through the household screening was high in the districts least covered by health-care services (particularly Rajshahi, Bangladesh, 49%; and to a lesser extent Vaishali in Bihar, India, 32.5%), and much lower in districts with greater availability of VL care (Muzaffarpur, India, 3.8%). On average 267 houses had to be visited, i.e., at least three to four working days per health worker, to identify a new VL (ranging from 1,432 houses in Muzaffarpur, India to only 166 houses in Rajshahi, Bangladesh). Knowledge of the disease and its vectors was good in India and Nepal but poor in Bangladesh (Rajshahi) where very little attention has been given to VL over the last decades. Although all socio-demographic indicators showed high levels of poverty, people in India preferred private medical practitioners for the treatment of VL, whereas in Nepal, and even more in Bangladesh, the public health-care sector was preferred. Delays between onset of symptoms and diagnosis as well as start of treatment was high. Reported non-adherence to treatment was particularly high in the more under-served districts and was mainly due to lack of resources. DISCUSSION: The findings suggest that (a) house-to-house screening may be useful in highly endemic districts with a poor passive case detection system, but further evidence on case finding adapted to local conditions has to be collected; (b) strengthening the quality of the public health sector is imperative in the three countries, especially in India, with its largely unregulated private-sector provision of VL care.


Assuntos
Controle de Doenças Transmissíveis/métodos , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/prevenção & controle , Programas Nacionais de Saúde , Animais , Atitude Frente a Saúde , Bangladesh/epidemiologia , Estudos Transversais , Humanos , Incidência , Índia/epidemiologia , Entrevistas como Assunto , Nepal/epidemiologia , Pobreza
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