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1.
PLoS Negl Trop Dis ; 14(10): e0008774, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-33079934

RESUMO

Visceral Leishmaniasis (VL) due to Leishmania donovani is a neglected protozoan parasitic disease in humans, which is usually fatal if untreated. Phlebotomus orientalis, the predominant VL vector in East Africa, is a highly exophilic/exophagic species that poses a major challenge to current Integrated Vector Management (IVM). Here we report results of pilot studies conducted in rural villages in Gedarif state, Sudan, to evaluate outdoor residual spraying of 20mg active ingredient (a.i.) /m2 deltamethrin insecticide applied to the characteristic household compound boundary reed fence and to the outside of household buildings (Outdoor Residual Insecticide Spraying, ODRS), and as an alternative, spraying restricted to the boundary fence only (Restricted Outdoor Residual Insecticide Spraying, RODRS). Four to six clusters of 20 households were assigned to insecticide treatments or control in three experiments. Changes in sand fly numbers were monitored over 2,033 trap-nights over 43-76 days follow-up in four sentinel houses per cluster relative to unsprayed control clusters. Sand fly numbers were monitored by sticky traps placed on the ground on the inside ("outdoor") and the outside ("peridomestic") of the boundary fence, and by CDC light traps suspended outdoors in the household compound. The effects of ODRS on sand fly numbers inside sleeping huts were monitored by insecticide knockdown. After a single application, ODRS reduced P. orientalis abundance by 83%-99% in outdoor and peridomestic trap locations. ODRS also reduced numbers of P. orientalis found resting inside sleeping huts. RODRS reduced outdoor and peridomestic P. orientalis by 60%-88%. By direct comparison, RODRS was 58%-100% as effective as ODRS depending on the trapping method. These impacts were immediate on intervention and persisted during follow-up, representing a large fraction of the P. orientalis activity season. Relative costs of ODRS and RODRS delivery were $5.76 and $3.48 per household, respectively. The study demonstrates the feasibility and high entomological efficacy of ODRS and RODRS, and the expected low costs relative to current IVM practises. These methods represent novel sand fly vector control tools against predominantly exophilic/exophagic sand fly vectors, aimed to lower VL burdens in Sudan, with potential application in other endemic regions in East Africa.

2.
Proc Natl Acad Sci U S A ; 117(41): 25742-25750, 2020 10 13.
Artigo em Inglês | MEDLINE | ID: mdl-32973088

RESUMO

Understanding of spatiotemporal transmission of infectious diseases has improved significantly in recent years. Advances in Bayesian inference methods for individual-level geo-located epidemiological data have enabled reconstruction of transmission trees and quantification of disease spread in space and time, while accounting for uncertainty in missing data. However, these methods have rarely been applied to endemic diseases or ones in which asymptomatic infection plays a role, for which additional estimation methods are required. Here, we develop such methods to analyze longitudinal incidence data on visceral leishmaniasis (VL) and its sequela, post-kala-azar dermal leishmaniasis (PKDL), in a highly endemic community in Bangladesh. Incorporating recent data on VL and PKDL infectiousness, we show that while VL cases drive transmission when incidence is high, the contribution of PKDL increases significantly as VL incidence declines (reaching 55% in this setting). Transmission is highly focal: 85% of mean distances from inferred infectors to their secondary VL cases were <300 m, and estimated average times from infector onset to secondary case infection were <4 mo for 88% of VL infectors, but up to 2.9 y for PKDL infectors. Estimated numbers of secondary cases per VL and PKDL case varied from 0 to 6 and were strongly correlated with the infector's duration of symptoms. Counterfactual simulations suggest that prevention of PKDL could have reduced overall VL incidence by up to 25%. These results highlight the need for prompt detection and treatment of PKDL to achieve VL elimination in the Indian subcontinent and provide quantitative estimates to guide spatiotemporally targeted interventions against VL.

3.
Parasit Vectors ; 13(1): 389, 2020 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-32736588

RESUMO

BACKGROUND: Sticky traps are generally viewed as interceptive sand fly sampling methods; although no previous experimental evidence has supported this assumption. In this study, we tested this assumption experimentally for Phlebotomus orientalis, the principal vector of visceral leishmaniasis in East Africa, and propose an explanation for the highly male-biased collection of sticky traps. METHODS: A number of field experiments were carried out in March-June 2016-2019, in Gedarif state, eastern Sudan. In the first experiment, we compared numbers of P. orientalis caught on sticky traps made of black, red, transparent, white, yellow, green and blue A4 size papers set simultaneously at different lunar light conditions. In the second and third experiments, we compared numbers of P. orientalis captured on sticky traps placed side-by-side horizontally or vertically on the ground, or horizontally on a 15 cm height stool. We also witnessed mating behaviour of sand flies following their landing on un-sticky papers placed on the ground. RESULTS: Phlebotomus orientalis showed significant attraction to white, yellow and transparent traps, with negligible numbers caught on the black and the red traps. Similarly, significantly higher numbers of P. orientalis were attracted to the horizontal traps, resulting in an 8-fold increase in sand fly trapping efficacy as compared to the vertical traps. Placing the traps on the stools resulted in significant reduction in this attraction. In contrast to the sticky traps that captured only very few females; we found that when male sand flies land on un-sticky white paper they successfully lure females and copulate with them. CONCLUSIONS: We demonstrate that, for P. orientalis, sticky traps are more attractant-based than interception-based sampling tools. Further, our findings support the notion that males of this sand fly species likely utilize the bright surface of the trap papers to perform mating rituals that attract the females for copulation. However, pre-mature death in the sticky oil hampers the completion of these rituals, and thus results in failure to attract the females. These findings inform our understanding of P. orientalis behaviour and have important implications for optimization of sticky trap design for vector surveillance purposes.

4.
PLoS Negl Trop Dis ; 14(7): e0008429, 2020 07.
Artigo em Inglês | MEDLINE | ID: mdl-32687498

RESUMO

BACKGROUND: Few prospective data exist on incidence of post kala-azar dermal leishmaniasis (PKDL) and visceral leishmaniasis (VL) relapse after different treatment regimens. METHODOLOGY/PRINCIPAL FINDINGS: A Phase IV trial included 1761 VL patients treated between 2012-2014 with single dose AmBisome (SDA; N = 891), miltefosine-paromomycin (Milt-PM; n = 512), or AmBisome-miltefosine (AmB-Milt; n = 358). Follow-up for PKDL and VL relapse was scheduled for 6, 12 and 24 months after treatment, lasting until 2017. Patients with lesions consistent with PKDL were tested by rK39 rapid test, and if positive, underwent skin-snip sampling, smear microscopy and PCR. Probable PKDL was defined by consistent lesions and positive rK39; confirmed PKDL required additional positive microscopy or PCR. PKDL and relapse incidence density were calculated by VL treatment and risk factors evaluated in Cox proportional hazards models. Among 1,750 patients who completed treatment, 79 had relapse and 104 PKDL. Relapse incidence density was 1.58, 2.08 and 0.40 per 1000 person-months for SDA, AmB-Milt and Milt-PM, respectively. PKDL incidence density was 1.29, 1.45 and 2.65 per 1000 person-months for SDA, AmB-Milt and Milt-PM. In multivariable models, patients treated with Milt-PM had lower relapse but higher PKDL incidence than those treated with SDA; AmB-Milt rates were not significantly different from those for SDA. Children <12 years were at higher risk for both outcomes; females had a higher risk of PKDL but not relapse. CONCLUSIONS/SIGNIFICANCE: Active surveillance for PKDL and relapse, followed by timely treatment, is essential to sustain the achievements of VL elimination programs in the Indian sub-continent.


Assuntos
Anfotericina B/administração & dosagem , Antiprotozoários/administração & dosagem , Leishmaniose Cutânea/parasitologia , Leishmaniose Visceral/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Incidência , Índia/epidemiologia , Leishmaniose Cutânea/patologia , Leishmaniose Visceral/parasitologia , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Adulto Jovem
5.
PLoS Negl Trop Dis ; 14(4): e0008253, 2020 04.
Artigo em Inglês | MEDLINE | ID: mdl-32324738

RESUMO

BACKGROUND: In the Mediterranean basin, Leishmania infantum is the causative agent of visceral leishmaniasis (VL), a zoonosis in which the dog is the primary domestic reservoir, although wildlife may have a leading role in the sylvatic cycle of the disease in some areas. Infections without disease are very frequent. There is limited information regarding the role that VL patients and asymptomatic infected individuals could be playing in the transmission of L. infantum. Xenodiagnosis of leishmaniasis has been used in this descriptive study to explore the role of symptomatic and asymptomatic infected individuals as reservoirs in a recent focus of leishmaniasis in southwestern Madrid, Spain. METHODOLOGY AND MAIN FINDINGS: Asymptomatic blood donors (n = 24), immunocompetent patients who were untreated (n = 12) or treated (n = 11) for visceral leishmaniasis (VL), and immunocompromised patients with VL (n = 3) were enrolled in the study. Their infectivity to Phlebotomus perniciosus was studied by indirect xenodiagnosis on peripheral blood samples. Quantitative polymerase chain reaction of blood samples from immunocompetent patients untreated for VL and immunocompromised untreated, treated and under secondary prophylaxis for VL was performed. Antibodies against Leishmania were studied by indirect fluorescent antibody and rK39-immunochromatographic tests. A lymphoproliferative assay with a soluble Leishmania antigen was used to screen for leishmaniasis infection in the healthy population. Sixty-two xenodiagnostic tests were carried out and 5,080 sand flies were dissected. Positive xenodiagnosis was recorded in four patients, with different sand fly infection rates: 1 immunosuppressed HIV / L. infantum coinfected asymptomatic patient, 1 immunosuppressed patient with multiple myeloma and symptomatic active VL, and 2 immunocompetent patients with untreated active VL. All blood donors were negative for both xenodiagnosis and conventional PCR. CONCLUSIONS / SIGNIFICANCE: There is no consensus amongst authors on the definition of an 'asymptomatic case' nor on the tools for screening; we, therefore, have adopted one for the sake of clarity. Immunocompetent subjects, both infected asymptomatics and those treated for VL, are limited in number and appear to have no epidemiological relevance. The impact is limited for immunocompetent patients with untreated active VL, whilst immunosuppressed individuals undergoing immunosuppressive therapy and immunosuppressed individuals HIV / L. infantum coinfected were the most infectious towards sand flies. It is noteworthy that the HIV / L. infantum coinfected patient with asymptomatic leishmaniasis was easily infectious to sand flies for a long time, despite being under continuous prophylaxis for leishmaniasis. Accordingly, screening for latent Leishmania infection in HIV-infected patients is recommended in scenarios where transmission occurs. In addition, screening for VL in HIV-infected patients who have spent time in VL-endemic areas should also be implemented in non-endemic areas. More research is needed to better understand if some asymptomatic coinfected individuals contribute to transmission as 'super-spreaders'.


Assuntos
Reservatórios de Doenças , Transmissão de Doença Infecciosa , Leishmania infantum/isolamento & purificação , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/transmissão , Adulto , Animais , Anticorpos Antiprotozoários/sangue , Doenças Assintomáticas/epidemiologia , DNA de Protozoário/sangue , Feminino , Humanos , Leucócitos Mononucleares/imunologia , Masculino , Pessoa de Meia-Idade , Psychodidae/parasitologia , Espanha/epidemiologia
6.
Semin Immunopathol ; 42(3): 231-246, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32189034

RESUMO

Progress has been made in the control or elimination of tropical diseases, with a significant reduction of incidence. However, there is a risk of re-emergence if the factors fueling transmission are not dealt with. Although it is essential to understand these underlying factors for each disease, asymptomatic carriers are a common element that may promote resurgence; their impact in terms of proportion in the population and role in transmission needs to be determined. In this paper, we review the current evidence on whether or not to treat asymptomatic carriers given the relevance of their role in the transmission of a specific disease, the efficacy and toxicity of existing drugs, the Public Health interest, and the benefit at an individual level, for example, in Chagas disease, to prevent irreversible organ damage. In the absence of other control tools such as vaccines, there is a need for safer drugs with good risk/benefit profiles in order to change the paradigm so that it addresses the complete infectious process beyond manifest disease to include treatment of non-symptomatic infected persons.

7.
PLoS Negl Trop Dis ; 13(9): e0007726, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31557162

RESUMO

BACKGROUND: An earlier open label, prospective, non-randomized, non-comparative, multi-centric study conducted within public health facilities in Bihar, India (CTRI/2012/08/002891) measured the field effectiveness of three new treatment regimens for visceral leishmaniasis (VL): single dose AmBisome (SDA), and combination therapies of AmBisome and miltefosine (AmB+Milt) and miltefosine and paromomycin (Milt+PM) up to 6 months follow-up. The National Vector Borne Disease Control Program (NVBDCP) recommended an extended follow up at 12 months post-treatment of the original study cohort to quantify late relapses. METHODS: The 1,761 patients enrolled in the original study with the three new regimens were contacted and traced between 10 and 36 months following completion of treatment to determine their health status and any occurrence of VL relapse. RESULTS: Of 1,761 patients enrolled in the original study, 1,368 were traced at the extended follow-up visit: 711 (80.5%), 295 (83.2%) and 362 (71.5%) patients treated with SDA, AmB+Milt and Milt+PM respectively. Of those traced, a total of 75 patients were reported to have relapsed by the extended follow-up; 45 (6.3%) in the SDA, 25 (8.5%) in the AmB+Milt and 5 (1.4%) in the Milt+PM arms. Of the 75 relapse cases, 55 had already been identified in the 6-months follow-up and 20 were identified as new cases of relapse at extended follow-up; 7 in the SDA, 10 in the AmB+Milt and 3 in the Milt+PM arms. CONCLUSION: Extending follow-up beyond the standard 6 months identified additional relapses, suggesting that 12-month sentinel follow-up may be useful as a programmatic tool to better identify and quantify relapses. With limited drug options, there remains an urgent need to develop effective new chemical entities (NCEs) for VL.


Assuntos
Antiprotozoários/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Adolescente , Anfotericina B/uso terapêutico , Criança , Pré-Escolar , Estudos de Coortes , Quimioterapia Combinada , Feminino , Seguimentos , Humanos , Índia , Masculino , Paromomicina/uso terapêutico , Fosforilcolina/análogos & derivados , Fosforilcolina/uso terapêutico , Recidiva , Resultado do Tratamento
8.
PLoS Negl Trop Dis ; 13(9): e0007724, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31525195

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is a parasitic disease, transmitted by the sand fly species Phlebotomus argentipes in the Indian sub-continent. Effective vector control is highly desirable to reduce vector density and human and vector contact in the endemic communities with the aim to curtail disease transmission. We evaluated the effect of long lasting insecticide treated bed nets (LLIN) and bed nets impregnated with slow-release insecticide tablet K-O TAB 1-2-3 (jointly insecticide-treated nets or ITN) on VL incidence in a highly endemic sub-district (upazila) in Bangladesh. METHODS: Several distributions of LLIN or K-O TAB 1-2-3 for self-impregnation of bed nets at home took place in Fulbaria upazila, Mymensigh district from 2004 to 2008 under three research projects, respectively funded by CDC, Atlanta, USA (2004) and WHO-TDR, Geneva, Switzerland (2006 & 2008). We included all households (n = 8142) in the 20 villages that had benefited in the past from one of these interventions (1295 donated LLIN and 11,918 local bed nets impregnated with K-O TAB 1-2-3) in the "exposed cohort". We recruited a "non-exposed cohort" in villages with contemporaneously similar incidence rates who had not received such vector control interventions (7729 HHs from nine villages). In both cohorts, we visited all families house to house and ascertained any VL cases for the 3 year period before and after the intervention. We evaluated the incidence rate (IR) of VL in both cohorts as primary endpoint, applying the difference-in-differences method. RESULTS: The study identified 1011 VL cases (IR 140.47/10,000 per year [py]) before the intervention, of which 534 and 477 cases in the intervention and control areas respectively. The IR was 144.13/10,000 py (534/37050) and 136.59/10,000 py (477/34923) in the intervention and control areas respectively, with no significant difference (p = 0.3901) before the intervention. After the intervention, a total of 555 cases (IR 77.11/10,000 py) were identified of which 178 (IR 48.04/10,000 py) in the intervention and 377 (107.95/10,000 py) in the control area. The intervention area had a significant lower IR than the control area during follow up, rate difference = -59.91, p<0.0001. The IR during follow up was significantly reduced by 96.09/10,000 py in the intervention area (p<0.0001) and 28.63/10,000 py in control area (p<0.0001) compared to baseline. There was a strong and significant overall effect of the ITN intervention, δ = -67.45, p <0.0001. Sex (OR = 1.36, p<0.0001) and age (OR = 0.99, p<0.0001) also had a significant effect on VL incidence. Male had a higher risk of VL than female and one year increase in age decreased the likelihood of VL by about 0.92%. Two third of the VL incidence occurred in the age range 2 to 30 years (median age of VL patients was 17 years). CONCLUSION: VL incidence rate was significantly lower in the ITN intervention cohort compared to control in Bangladesh. Some bias due to more intense screen-and-treat activities or other interventions in the intervention area cannot be ruled out. Nonetheless, given their feasibility and sustainability, ITNs should be considered for integrated vector control during the maintenance phase of the VL elimination programme.


Assuntos
Controle de Insetos/métodos , Mosquiteiros Tratados com Inseticida , Leishmaniose Visceral/prevenção & controle , Adolescente , Adulto , Animais , Bangladesh/epidemiologia , Criança , Pré-Escolar , Estudos de Coortes , Feminino , Humanos , Incidência , Lactente , Insetos Vetores , Inseticidas , Leishmaniose Visceral/epidemiologia , Masculino , Pessoa de Meia-Idade , Nitrilos , Phlebotomus , Piretrinas , Estudos Retrospectivos
9.
PLoS Negl Trop Dis ; 13(8): e0007653, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-31415565

RESUMO

BACKGROUND: We investigated the relationship of treatment regimens for visceral leishmaniasis (VL) with post-kala-azar dermal leishmaniasis (PKDL) and visceral leishmaniasis relapse (VLR) development. METHODS: Study subjects included cohorts of patients cured of VL since treatment with monotherapy by sodium stibogluconate (SSG), miltefosine (MF), paromomycin intramuscular injection (PMIM), liposomal amphotericin B [AmBisome (AMB)] in a single dose (SDAMB) and in multidose (MDAMB), and combination therapies by AMB+PMIM, AMB+MF, and PMIM+MF. Follow up period was 4 years after treatment. Cohorts were prospective except SSG (retrospective) and MF (partially retrospective). We compared incidence proportion and rate in 100-person-4year of PKDL and VLR by treatment regimens using univariate and multivariate analysis. FINDINGS: 974 of 984 enrolled participants completed the study. Overall incidence proportion for PKDL and VLR was 12.3% (95% CI, 10.4%-14.5%) and 7.0% (95% CI, 5.6%-8.8%) respectively. The incidence rate (95% CI) of PKDL and VLR was 14.0 (8.6-22.7) and 7.6 (4.1-14.7) accordingly. SSG cohort had the lowest incidence rate of PKDL at 3.0 (1.3-7.3) and VLR at 1.8 (0.6-5.6), followed by MDAMB at 8.2 (4.3-15.7) for PKDL and at 2.7 (0.9-8.4) for VLR. INTERPRETATION: Development of PKDL and VLR is related with treatment regimens for VL. SSG and MDAMB resulted in less incidence of PKDL and VLR compared to other treatment regimens. MDAMB should be considered for VL as a first step for prevention of PKDL and VLR since SSG is highly toxic and not recommended for VL.


Assuntos
Antiprotozoários/uso terapêutico , Tratamento Farmacológico/métodos , Leishmaniose Cutânea/epidemiologia , Leishmaniose Visceral/complicações , Leishmaniose Visceral/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Bangladesh/epidemiologia , Quimioterapia Combinada/métodos , Feminino , Humanos , Incidência , Injeções Intramusculares , Masculino , Pessoa de Meia-Idade , Estudos Prospectivos , Recidiva , Estudos Retrospectivos , Resultado do Tratamento , Adulto Jovem
10.
PLoS Negl Trop Dis ; 13(2): e0007092, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30802261

RESUMO

BACKGROUND: Major depressive disorder (MDD) associated with chronic neglected tropical diseases (NTDs) has been identified as a significant and overlooked contributor to overall disease burden. Cutaneous leishmaniasis (CL) is one of the most prevalent and stigmatising NTDs, with an incidence of around 1 million new cases of active CL infection annually. However, the characteristic residual scarring (inactive CL) following almost all cases of active CL has only recently been recognised as part of the CL disease spectrum due to its lasting psychosocial impact. METHODS AND FINDINGS: We performed a multi-language systematic review of the psychosocial impact of active and inactive CL. We estimated inactive CL (iCL) prevalence for the first time using reported WHO active CL (aCL) incidence data that were adjusted for life expectancy and underreporting. We then quantified the disability (YLD) burden of co-morbid MDD in CL using MDD disability weights at three severity levels. Overall, we identified 29 studies of CL psychological impact from 5 WHO regions, representing 11 of the 50 highest burden countries for CL. We conservatively calculated the disability burden of co-morbid MDD in CL to be 1.9 million YLDs, which equalled the overall (DALY) disease burden (assuming no excess mortality in depressed CL patients). Thus, upon inclusion of co-morbid MDD alone in both active and inactive CL, the DALY burden was seven times higher than the latest 2016 Global Burden of Disease study estimates, which notably omitted both psychological impact and inactive CL. CONCLUSIONS: Failure to include co-morbid MDD and the lasting sequelae of chronic NTDs, as exemplified by CL, leads to large underestimates of overall disease burden.


Assuntos
Efeitos Psicossociais da Doença , Transtorno Depressivo Maior/complicações , Saúde Global , Leishmaniose Cutânea/complicações , Comorbidade , Transtorno Depressivo Maior/parasitologia , Carga Global da Doença , Humanos , Incidência , Expectativa de Vida , Doenças Negligenciadas/complicações , Doenças Negligenciadas/parasitologia , Prevalência , Psicologia , Anos de Vida Ajustados por Qualidade de Vida
11.
PLoS Negl Trop Dis ; 13(2): e0007132, 2019 02.
Artigo em Inglês | MEDLINE | ID: mdl-30789910

RESUMO

BACKGROUND: The long-term treatment outcome of visceral leishmaniasis (VL) patients with HIV co-infection is complicated by a high rate of relapse, especially when the CD4 count is low. Although use of secondary prophylaxis is recommended, it is not routinely practiced and data on its effectiveness and safety are limited. METHODS: A prospective cohort study was conducted in Northwest Ethiopia from August 2014 to August 2017 (NCT02011958). HIV-VL patients were followed for up to 12 months. Patients with CD4 cell counts below 200/µL at the end of VL treatment received pentamidine prophylaxis starting one month after parasitological cure, while those with CD4 count ≥200 cells/µL were followed without secondary prophylaxis. Compliance, safety and relapse-free survival, using Kaplan-Meier analysis methods to account for variable time at risk, were summarised. Risk factors for relapse or death were analysed. RESULTS: Fifty-four HIV patients were followed. The probability of relapse-free survival at one year was 50% (95% confidence interval [CI]: 35-63%): 53% (30-71%) in 22 patients with CD4 ≥200 cells/µL without pentamidine prophylaxis and 46% (26-63%) in 29 with CD4 <200 cells/µL who started pentamidine. Three patients with CD4 <200 cells/µL did not start pentamidine. Amongst those with CD4 ≥200 cells/µL, VL relapse was an independent risk factor for subsequent relapse or death (adjusted rate ratio: 5.42, 95% CI: 1.1-25.8). Except for one case of renal failure which was considered possibly related to pentamidine, there were no drug-related safety concerns. CONCLUSION: The relapse-free survival rate for VL patients with HIV was low. Relapse-free survival of patients with CD4 count <200cells/µL given pentamidine secondary prophylaxis appeared to be comparable to patients with a CD4 count ≥200 cells/µL not given prophylaxis. Patients with relapsed VL are at higher risk for subsequent relapse and should be considered a priority for secondary prophylaxis, irrespective of their CD4 count.


Assuntos
Antiprotozoários/uso terapêutico , Infecções por HIV/complicações , Leishmaniose Visceral/complicações , Pentamidina/uso terapêutico , Adulto , Contagem de Linfócito CD4 , Estudos de Coortes , Coinfecção , Etiópia/epidemiologia , Feminino , Infecções por HIV/epidemiologia , Humanos , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/epidemiologia , Masculino , Pessoa de Meia-Idade , Prognóstico , Estudos Prospectivos , Fatores de Risco , Análise de Sobrevida , Adulto Jovem
13.
PLoS Negl Trop Dis ; 13(1): e0006988, 2019 01.
Artigo em Inglês | MEDLINE | ID: mdl-30653490

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) in human immunodeficiency virus (HIV) co-infected patients requires special case management. AmBisome monotherapy at 40 mg/kg is recommended by the World Health Organization. The objective of the study was to assess if a combination of a lower dose of AmBisome with miltefosine would show acceptable efficacy at the end of treatment. METHODOLOGY/PRINCIPAL FINDINGS: An open-label, non-comparative randomized trial of AmBisome (30 mg/kg) with miltefosine (100 mg/day for 28 days), and AmBisome monotherapy (40 mg/kg) was conducted in Ethiopian VL patients co-infected with HIV (NCT02011958). A sequential design was used with a triangular continuation region. The primary outcome was parasite clearance at day 29, after the first round of treatment. Patients with clinical improvement but without parasite clearance at day 29 received a second round of the allocated treatment. Efficacy was evaluated again at day 58, after completion of treatment. Recruitment was stopped after inclusion of 19 and 39 patients in monotherapy and combination arms respectively, as per pre-specified stopping rules. At D29, intention-to-treat efficacy in the AmBisome arm was 70% (95% CI 45-87%) in the unadjusted analysis, and 50% (95% CI 27-73%) in the adjusted analysis, while in the combination arm, it was 81% (95% CI 67-90%) and 67% (95% CI 48-82%) respectively. At D58, the adjusted efficacy was 55% (95% CI 32-78%) in the monotherapy arm, and 88% (95% CI 79-98%) in the combination arm. No major safety concerns related to the study medication were identified. Ten SAEs were observed within the treatment period, and 4 deaths unrelated to the study medication. CONCLUSIONS/SIGNIFICANCE: The extended treatment strategy with the combination regimen showed the highest documented efficacy in HIV-VL patients; these results support a recommendation of this regimen as first-line treatment strategy for HIV-VL patients in eastern Africa. TRIAL REGISTRATION NUMBER: www.clinicaltrials.gov NCT02011958.


Assuntos
Anfotericina B/uso terapêutico , Antiprotozoários/uso terapêutico , Leishmaniose Visceral/tratamento farmacológico , Fosforilcolina/análogos & derivados , Adulto , Antirretrovirais/uso terapêutico , Coinfecção/tratamento farmacológico , Coinfecção/virologia , Quimioterapia Combinada , Etiópia , Feminino , Infecções por HIV/tratamento farmacológico , Humanos , Leishmania donovani/isolamento & purificação , Masculino , Pessoa de Meia-Idade , Carga Parasitária , Fosforilcolina/uso terapêutico , Resultado do Tratamento , Adulto Jovem
14.
Clin Infect Dis ; 69(2): 251-258, 2019 07 02.
Artigo em Inglês | MEDLINE | ID: mdl-30357373

RESUMO

BACKGROUND: On the Indian subcontinent, visceral leishmaniasis (VL) incidence is on track to reach elimination goals by 2020 in nearly all endemic districts. Although not included in official targets, previous data suggest post-kala-azar dermal leishmaniasis (PKDL) patients can act as an infection reservoir. METHODS: We conducted xenodiagnosis on 47 PKDL patients and 15 VL patients using laboratory-reared Phlebotomus argentipes. In direct xenodiagnosis, flies were allowed to feed on the patient's skin for 15 minutes. For indirect xenodiagnosis, flies were fed through a membrane on the patient's blood. Five days later, blood-fed flies were dissected and examined by microscopy and/or polymerase chain reaction (PCR). A 3-mm skin snip biopsy (PKDL) or venous blood (VL) was processed by quantitative PCR. RESULTS: Twenty-seven PKDL patients (57.4%) had positive results by direct and/or indirect xenodiagnosis. Direct was significantly more sensitive than indirect xenodiagnosis (55.3% vs 6.4%, P < .0001). Those with positive xenodiagnosis had median skin parasite loads >1 log10 unit higher than those with negative results (2.88 vs 1.66, P < .0001). In a multivariable model, parasite load, nodular lesions, and positive skin microscopy were significantly associated with positive xenodiagnosis. Blood parasite load was the strongest predictor for VL. Compared to VL, nodular PKDL was more likely and macular PKDL less likely to result in positive xenodiagnosis, but neither difference reached statistical significance. CONCLUSIONS: Nodular and macular PKDL, and VL, can be infectious to sand flies. Active PKDL case detection and prompt treatment should be instituted and maintained as an integral part of VL control and elimination programs.


Assuntos
Reservatórios de Doenças , Transmissão de Doença Infecciosa , Insetos Vetores/parasitologia , Leishmania donovani/isolamento & purificação , Leishmaniose Cutânea/transmissão , Leishmaniose Visceral/transmissão , Psychodidae/parasitologia , Adulto , Animais , Feminino , Humanos , Insetos Vetores/fisiologia , Leishmaniose Cutânea/parasitologia , Leishmaniose Visceral/parasitologia , Masculino , Pessoa de Meia-Idade , Psychodidae/fisiologia
15.
Clin Infect Dis ; 68(9): 1530-1538, 2019 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-30188978

RESUMO

BACKGROUND: Convenient, safe, and effective treatments for visceral leishmaniasis in Eastern African children are lacking. Miltefosine, the only oral treatment, failed to achieve adequate efficacy, particularly in children, in whom linear dosing (2.5 mg/kg/day for 28 days) resulted in a 59% cure rate, with lower systemic exposure than in adults. METHODS: We conducted a Phase II trial in 30 children with visceral leishmaniasis, aged 4-12 years, to test whether 28 days of allometric miltefosine dosing safely achieves a higher systemic exposure than linear dosing. RESULTS: Miltefosine accumulated during treatment. Median areas under the concentration time curve from days 0-210 and plasma maximum concentration values were slightly higher than those reported previously for children on linear dosing, but not dose-proportionally. Miltefosine exposure at the start of treatment was increased, with higher median plasma concentrations on day 7 (5.88 versus 2.67 µg/mL). Concentration-time curves were less variable, avoiding the low levels of exposure observed with linear dosing. The 210-day cure rate was 90% (95% confidence interval, 73-98%), similar to that previously described in adults. There were 19 treatment-related adverse events (AEs), but none caused treatment discontinuation. There were 2 serious AEs: both were unrelated to treatment and both patients were fully recovered. CONCLUSIONS: Allometric miltefosine dosing achieved increased and less-variable exposure than linear dosing, though not reaching the expected exposure levels. The new dosing regimen safely increased the efficacy of miltefosine for Eastern African children with visceral leishmaniasis. Further development of miltefosine should adopt allometric dosing in pediatric patients. CLINICAL TRIALS REGISTRATION: NCT02431143.


Assuntos
Antiprotozoários/farmacocinética , Leishmaniose Visceral/tratamento farmacológico , Fosforilcolina/análogos & derivados , África Oriental , Antiprotozoários/sangue , Antiprotozoários/farmacologia , Área Sob a Curva , Criança , Pré-Escolar , Esquema de Medicação , Feminino , Humanos , Leishmania donovani/efeitos dos fármacos , Leishmania donovani/crescimento & desenvolvimento , Leishmania donovani/patogenicidade , Leishmaniose Visceral/sangue , Leishmaniose Visceral/parasitologia , Leishmaniose Visceral/patologia , Masculino , Segurança do Paciente , Fosforilcolina/sangue , Fosforilcolina/farmacocinética , Fosforilcolina/farmacologia , Resultado do Tratamento
16.
PLoS Negl Trop Dis ; 12(11): e0006778, 2018 11.
Artigo em Inglês | MEDLINE | ID: mdl-30408042

RESUMO

BACKGROUND: Ethiopia bears a high burden of visceral leishmaniasis (VL). Early access to VL diagnosis and care improves clinical prognosis and reduces transmission from infected humans; however, significant obstacles exist. The approximate 250,000 seasonal mobile workers (MW) employed annually in northwestern Ethiopia may be particularly disadvantaged and at risk of VL acquisition and death. Our study aimed to assess barriers, and recommend interventions to increase access, to VL diagnosis and care among MWs. METHODOLOGY/PRINCIPAL FINDINGS: In 2017, 50 interviews and 11 focus group discussions were conducted with MWs, mobile residents, VL patients and caretakers, community leaders and healthcare workers in Kafta Humera District, Tigray. Participants reported high vulnerability to VL among MWs and residents engaged in transitory work. Multiple visits to health facilities were consistently needed to access VL diagnosis. Inadequate healthcare worker training, diagnostic test kit unavailability at the primary healthcare level, lack of VL awareness, insufficient finances for care-seeking and prioritization of income-generating activities were significant barriers to diagnosis and care. Social (decision-making and financial) support strongly and positively influenced care-seeking; workers unable to receive salary advances, compensation for partial work, or peer assistance for contract completion were particularly disadvantaged. Participants recommended the government/stakeholders intervene to ensure: MWs access to bed-nets, food, shelter, water, and healthcare at farms or sick leave; decentralization of diagnostic tests to primary healthcare facilities; surplus medications/staff during the peak season; improved referral/feedback/reporting/training within the health system; free comprehensive healthcare for all VL-related services; and community health education. CONCLUSIONS/SIGNIFICANCE: Contrary to what health policy for VL dictates in this endemic setting, study participants reported very poor access to diagnosis and, consequently, significantly delayed access to treatment. Interventions tailored to the socio-economic and health needs of MWs (and other persons suffering from VL) are urgently needed to reduce health disparities and the VL burden.


Assuntos
Leishmaniose Visceral/diagnóstico , Adulto , Idoso , Etiópia/epidemiologia , Feminino , Instalações de Saúde , Acesso aos Serviços de Saúde , Humanos , Leishmaniose Visceral/economia , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/terapia , Masculino , Pessoa de Meia-Idade , Pesquisa Qualitativa , Estações do Ano , Migrantes/estatística & dados numéricos , Adulto Jovem
17.
PLoS Negl Trop Dis ; 12(10): e0006830, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30346949

RESUMO

BACKGROUND: In 2010, WHO recommended the use of new short-course treatment regimens in kala-azar elimination efforts for the Indian subcontinent. Although phase 3 studies have shown excellent results, there remains a lack of evidence on a wider treatment population and the safety and effectiveness of these regimens under field conditions. METHODS: This was an open label, prospective, non-randomized, non-comparative, multi-centric trial conducted within public health facilities in two highly endemic districts and a specialist referral centre in Bihar, India. Three treatment regimens were tested: single dose AmBisome (SDA), concomitant miltefosine and paromomycin (Milt+PM), and concomitant AmBisome and miltefosine (AmB+Milt). Patients with complicated disease or significant co-morbidities were treated in the SDA arm. Sample sizes were set at a minimum of 300 per arm, taking into account inter-site variation and an estimated failure risk of 5% with 5% precision. Outcomes of drug effectiveness and safety were measured at 6 months. The trial was prospectively registered with the Clinical Trials Registry India: CTRI/2012/08/002891. RESULTS: Out of 1,761 patients recruited, 50.6% (n = 891) received SDA, 20.3% (n = 358) AmB+Milt and 29.1% (n = 512) Milt+PM. In the ITT analysis, the final cure rates were SDA 91.4% (95% CI 89.3-93.1), AmB+Milt 88.8% (95% CI 85.1-91.9) and Milt+PM 96.9% (95% CI 95.0-98.2). In the complete case analysis, cure rates were SDA 95.5% (95% CI 93.9-96.8), AmB+Milt 95.5% (95% CI 92.7-97.5) and Milt+PM 99.6% (95% CI 98.6-99.9). All three regimens were safe, with 5 severe adverse events in the SDA arm, two of which were considered to be drug related. CONCLUSION: All regimens showed acceptable outcomes and safety profiles in a range of patients under field conditions. Phase IV field-based studies, although extremely rare for neglected tropical diseases, are good practice and an important step in validating the results of more restrictive hospital-based studies before widespread implementation, and in this case contributed to national level policy change in India. TRIAL REGISTRATION: Clinical trial is registered at Clinical trial registry of India (CTRI/2012/08/002891, Registered on 16/08/2012, Trial Registered Prospectively).


Assuntos
Antiprotozoários/administração & dosagem , Antiprotozoários/efeitos adversos , Quimioterapia Combinada/efeitos adversos , Quimioterapia Combinada/métodos , Leishmaniose Visceral/tratamento farmacológico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anfotericina B/administração & dosagem , Anfotericina B/efeitos adversos , Criança , Pré-Escolar , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/epidemiologia , Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos/patologia , Feminino , Humanos , Índia , Masculino , Pessoa de Meia-Idade , Paromomicina/administração & dosagem , Paromomicina/efeitos adversos , Fosforilcolina/administração & dosagem , Fosforilcolina/efeitos adversos , Fosforilcolina/análogos & derivados , Estudos Prospectivos , Resultado do Tratamento , Adulto Jovem
18.
Clin Microbiol Rev ; 31(4)2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30158301

RESUMO

Research in visceral leishmaniasis in the last decade has been focused on how better to use the existing medicines as monotherapy or in combination. Systematic research by geographical regions has shown that a universal treatment is far from today's reality. Substantial progress has been made in the elimination of kala-azar in South Asia, with a clear strategy on first- and second-line therapy options of single-dose liposomal amphotericin B and a combination of paromomycin and miltefosine, respectively, among other interventions. In Eastern Africa, sodium stibogluconate (SSG) and paromomycin in combination offer an advantage compared to the previous SSG monotherapy, although not exempted of limitations, as this therapy requires 17 days of painful double injections and bears the risk of SSG-related cardiotoxicity. In this region, attempts to improve the combination therapy have been unsuccessful. However, pharmacokinetic studies have led to a better understanding of underlying mechanisms, like the underexposure of children to miltefosine treatment, and an improved regimen using an allometric dosage. Given this global scenario of progress and pitfalls, we here review what steps need to be taken with existing medicines and highlight the urgent need for oral drugs. Furthermore, it should be noted that six candidates belonging to five new chemical classes are reaching phase I, ensuring an optimistic near future.


Assuntos
Antiprotozoários/uso terapêutico , Descoberta de Drogas/tendências , Leishmaniose Visceral/tratamento farmacológico , Pesquisa Biomédica/tendências , Humanos
19.
Cochrane Database Syst Rev ; 3: CD012261, 2018 03 26.
Artigo em Inglês | MEDLINE | ID: mdl-29578237

RESUMO

BACKGROUND: Visceral leishmaniasis (VL) is a disease caused by a parasite, which can lead to death if untreated. Poor nutritional status hastens the progression of VL infection, and VL worsens malnutrition status. Malnutrition is one of the poor prognostic factors identified for leishmaniasis. However, the effects of nutritional supplementation in people treated for VL are not known. OBJECTIVES: To assess the effects of oral nutritional supplements in people being treated with anti-leishmanial drug therapy for VL. SEARCH METHODS: We searched the Cochrane Infectious Diseases Group (CIDG) Specialized Register, CENTRAL, MEDLINE, Embase, LILACS, and two trial registers up to 12 September 2017. We checked conference proceedings and WHO consultative meeting reports, the reference lists of key documents and existing reviews, and contacted experts and nutritional supplement companies. SELECTION CRITERIA: Randomized controlled trials (RCTs), quasi-randomized controlled trials (quasi-RCTs), and non-randomized controlled trials (NRCTs) of any oral nutritional supplement, compared to no nutritional intervention, placebo, or dietary advice alone, in people being treated for VL. DATA COLLECTION AND ANALYSIS: Two review authors independently screened the literature search results for studies that met the inclusion criteria. We had planned for two review authors to independently extract data and assess the risk of bias of the included studies. We planned to follow the Cochrane standard methodological procedures for assessing risk of bias and analysing the data. MAIN RESULTS: We identified no eligible studies for this review, either completed or ongoing. AUTHORS' CONCLUSIONS: We found no studies, either completed or ongoing, that assessed the effects of oral nutritional supplements in people with VL who were being treated with anti-leishmanial drug therapy. Thus, we could not draw any conclusions on the impact of these interventions on primary cure of VL, definitive cure of VL, treatment completion, self-reported recovery from illness or resolution of symptoms, weight gain, increased skinfold thickness, other measures of lean or total mass, or growth in children.This absence of evidence should not be interpreted as evidence of no effect for nutritional supplements in people under VL treatment. It means that we did not identify research that fulfilled our review inclusion criteria.The effects of oral nutritional supplements in people with VL who are being treated with anti-leishmanial drug therapy have yet to be determined by rigorous experimental studies, such as cluster-randomized trials, that focus on outcomes relevant for patients.


Assuntos
Suplementos Nutricionais , Leishmaniose Visceral/tratamento farmacológico , Desnutrição/terapia , Terapia Nutricional , Humanos
20.
PLoS Negl Trop Dis ; 11(11): e0005877, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-29145397

RESUMO

BACKGROUND: The South-East Asia Region Kala-azar Elimination Programme (KAEP) is expected to enter the consolidation phase in 2017, which focuses on case detection, vector control, and identifying potential sources of infection. Post-kala-azar dermal leishmaniasis (PKDL) is thought to play a role in the recurrence of visceral leishmaniasis (VL)/kala-azar outbreaks, and control of PKDL is among the priorities of the KAEP. METHODOLOGY AND PRINCIPAL FINDING: We reviewed the literature with regard to PKDL in Asia and interpreted the findings in relation to current intervention methods in the KAEP in order to make recommendations. There is a considerable knowledge gap regarding the pathophysiology of VL and PKDL, especially the underlying immune responses. Risk factors (of which previous VL treatments may be most important) are poorly understood and need to be better defined. The role of PKDL patients in transmission is largely unknown, and there is insufficient information about the importance of duration, distribution and severity of the rash, time of onset, and self-healing. Current intervention methods focus on active case detection and treatment of all PKDL cases with miltefosine while there is increasing drug resistance. The prevention of PKDL by improved VL treatment currently receives insufficient attention. CONCLUSION AND SIGNIFICANCE: PKDL is a heterogeneous and dynamic condition, and patients differ with regard to time of onset after VL, chronicity, and distribution and appearance of the rash, as well as immune responses (including tendency to self-heal), all of which may vary over time. It is essential to fully describe the pathophysiology in order to make informed decisions on the most cost-effective approach. Emphasis should be on early detection of those who contribute to transmission and those who are in need of treatment, for whom short-course, effective, and safe drug regimens should be available. The prevention of PKDL should be emphasised by innovative and improved treatment for VL, which may include immunomodulation.


Assuntos
Erradicação de Doenças/organização & administração , Leishmaniose Cutânea/epidemiologia , Leishmaniose Visceral/epidemiologia , Leishmaniose Visceral/prevenção & controle , Serviços Preventivos de Saúde , Ásia Sudeste/epidemiologia , Surtos de Doenças/prevenção & controle , Feminino , Humanos , Índia/epidemiologia , Leishmania donovani/isolamento & purificação , Leishmaniose Cutânea/parasitologia , Leishmaniose Visceral/tratamento farmacológico , Leishmaniose Visceral/parasitologia , Masculino , Prevalência , Recidiva , Fatores de Risco
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