Cost of visceral leishmaniasis care in Brazil

Vaccine value profile for leishmaniasis

Leishmania infections are global, occurring in 98 countries and all World Health Organization (WHO) regions with 600 million to 1 billion people at risk of infection. Visceral leishmaniasis is associated with almost 20,000 reported deaths annually, with children under 5 years of age being at the greatest risk of mortality. Amongst WHO-recognised Neglected Tropical Diseases (NTDs), leishmaniasis is one of the most important in terms of mortality and morbidity. With an increasing global burden of disease and a growing threat from climate change, urbanisation and drug resistance, there remains an imperative to develop leishmaniasis vaccines. New tools to understand correlates of protection and to assess vaccine efficacy are being developed to ease the transition into larger scale efficacy trials or provide alternate routes to licensure. Early indications suggest a diverse portfolio of manufacturers exists in endemic countries with an appetite to develop leishmaniasis vaccines. This Vaccine Value Profile (VVP) provides a high-level, comprehensive assessment of the currently available data to inform the potential public health, economic, and societal value of leishmaniasis vaccines. The leishmaniasis VVP was developed by a working group of subject matter experts from academia, public health groups, policy organizations, and non-profit organizations. All contributors have extensive expertise on various elements of the leishmaniasis VVP and have collectively described the state of knowledge and identified the current gaps. The VVP was developed using only existing and publicly available information.

What else in times of COVID-19? The role of minimally invasive autopsy for the differential diagnosis of acute respiratory failure in a case of kala-azar

Visceral leishmaniasis (VL) is a chronic vector-borne zoonotic disease caused by trypanosomatids, considered endemic in 98 countries, mainly associated with poverty. About 50,000-90,000 cases of VL occur annually worldwide, and Brazil has the second largest number of cases in the world. The clinical picture of VL is fever, hepatosplenomegaly, and pancytopenia, progressing to death in 90% of cases due to secondary infections and multi-organ failure, if left untreated. We describe the case of a 25-year-old female who lived in the metropolitan area of Sao Paulo, who had recently taken touristic trips to several rural areas in Southeastern Brazil and was diagnosed post-mortem. During the hospitalization in a hospital reference for the treatment of COVID-19, the patient developed acute respiratory failure, with chest radiographic changes, and died due to refractory shock. The ultrasound-guided minimally invasive autopsy diagnosed VL (macrophages containing amastigote forms of Leishmania in the spleen, liver and bone marrow), as well as pneumonia and bloodstream infection by gram-negative bacilli.

[Hospital admissions due to neglected tropical diseases in Piauí, in the Northeast region of Brazil: costs, time trends, and spatial patterns, 2001-2018]

To characterize the magnitude of hospital admissions and costs of patients with neglected tropical diseases, their time trends, and spatial patterns in Piauí, in the Northeast Region of Brazil, in 2001-2018. Ecological study of mixed designs, with calculation of relative risk (RR), time-trend analysis by Poisson regression, and inflection points, using data from neglected tropical diseases Hospital Admission Authorizations available in the Hospital Information System of the Brazilian Unified National Health System (SIH/SUS). Data showed 49,832 hospital admissions due to neglected tropical diseases in the period (rate: 86.70/100,000 inhabitants; 95%CI: 83.47; 89.93); of these, dengue (78.2%), leishmaniasis (8.6%), and leprosy (6.4%). The total cost was BRL 34,481,815.43, 42.8% of which referred to medium complexity cases. Higher risks of hospitalization occurred among people ≥ 60 years (RR = 1.8; 95%CI: 1.5; 2.2), mixed race/color (RR = 1.7; 95%CI: 1.1; 2.4), residents of municipalities presenting medium social vulnerability (RR = 1.5; 95% CI: 1.3; 1.6), and population size (RR = 1.6; 95%CI: 1.4; 1.9). The time trend showed a reduction in hospital admissions due to neglected tropical diseases, 2003-2018 (annual percent change - APC: -10.3; 95%CI: -14.7; -5.6). The spatial pattern showed clusters with higher rates of hospital admission in border municipalities located south of the Mid-north macroregion, north of the Semiarid macroregion, and south of the Cerrados macroregion. Piauí remains with high hospital admission rates and costs for neglected tropical diseases. Despite the reduction in time trends, knowledge burden, population groups, and municipalities at greater risk and vulnerability reinforce the importance of monitoring and strengthening control actions to maintain the reduction of the burden and costs of hospital admission due to neglected tropical diseases in the state.

Estimating the global demand curve for a leishmaniasis vaccine: A generalisable approach based on global burden of disease estimates

Background

A pressing need exists to develop vaccines for neglected diseases, including leishmaniasis. However, the development of new vaccines is dependent on their value to two key players–vaccine developers and manufacturers who need to have confidence in the global demand in order to commit to research and production; and governments (or other international funders) who need to signal demand based on the potential public health benefits of the vaccine in their local context, as well as its affordability. A detailed global epidemiological analysis is rarely available before a vaccine enters a market due to lack of resources as well as insufficient global data necessary for such an analysis. Our study seeks to bridge this information gap by providing a generalisable approach to estimating the commercial and public health value of a vaccine in development relying primarily on publicly available Global Burden of Disease (GBD) data. This simplified approach is easily replicable and can be used to guide discussions and investments into vaccines and other health technologies where evidence constraints exist. The approach is demonstrated through the estimation of the demand curve for a future leishmaniasis vaccine.

Methodology/Principal findings

We project the ability to pay over the period 2030–2040 for a vaccine preventing cutaneous and visceral leishmaniasis (CL / VL), using an illustrative set of countries which account for most of the global disease burden. First, based on previous work on vaccine demand projections in these countries and CL / VL GBD-reported incidence rates, we project the potential long-term impact of the vaccine on disability-adjusted life years (DALYs) averted as a result of reduced incidence. Then, we apply an economic framework to our estimates to determine vaccine affordability based on the abilities to pay of governments and global funders, leading to estimates of the demand and market size. Based on our estimates, the maximum ability-to-pay of a leishmaniasis vaccine (per course, including delivery costs), given the current estimates of incidence and population at risk, is higher than $5 for 25–30% of the countries considered, with the average value-based maximum price, weighted by quantity demanded, being $5.7–6 [$0.3 - $34.5], and total demand of over 560 million courses.

Conclusion/Significance

Our results demonstrate that both the quantity of vaccines estimated to be required by the countries considered as well as their ability-to-pay could make a vaccine for leishmaniasis commercially attractive to potential manufacturers. The methodology used can be equally applied to other technology developments targeting health in developing countries.

Overcoming roadblocks in the development of vaccines for leishmaniasis

INTRODUCTION

The leishmaniases represent a group of parasitic diseases caused by infection with one of several species of Leishmania parasites. Disease presentation varies because of differences in parasite and host genetics and may be influenced by additional factors such as host nutritional status or co-infection. Studies in experimental models of Leishmania infection, vaccination of companion animals and human epidemiological data suggest that many forms of leishmaniasis could be prevented by vaccination, but no vaccines are currently available for human use.

AREAS COVERED

We describe some of the existing roadblocks to the development and implementation of an effective leishmaniasis vaccine, based on a review of recent literature found on PubMed, BioRxiv and MedRxiv. In addition to discussing scientific unknowns that hinder vaccine candidate identification and selection, we explore gaps in knowledge regarding the commercial and public health value propositions underpinning vaccine development and provide a route map for future research and advocacy.

EXPERT OPINION

Despite significant progress, leishmaniasis vaccine development remains hindered by significant gaps in understanding that span the vaccine development pipeline. Increased coordination and adoption of a more holistic view to vaccine development will be required to ensure more rapid progress in the years ahead.

Vulnerabilities to and the Socioeconomic and Psychosocial Impacts of the Leishmaniases: A Review

The leishmaniases are a group of four vector-borne neglected tropical diseases (NTDs) with 1.6 billion people in some 100 countries at risk. They occur in certain eco-epidemiological foci that reflect manipulation by human activities, such as migration, urbanization and deforestation, of which poverty, conflict and climate change are key drivers. Given their synergistic impacts, risk factors and the vulnerabilities of poor populations and the launch of a new 2030 roadmap for NTDs in the context of the global sustainability agenda, it is warranted to update the state of knowledge of the leishmaniases and their effects. Using existing literature, we review socioeconomic and psychosocial impacts of leishmaniasis within a framework of risk factors and vulnerabilities to help inform policy interventions. Studies show that poverty is an overarching primary risk factor. Low-income status fosters inadequate housing, malnutrition and lack of sanitation, which create and exacerbate complexities in access to care and treatment outcomes as well as education and awareness. The co-occurrence of the leishmaniases with malnutrition and HIV infection further complicate diagnosis and treatment, leading to poor diagnostic outcomes and therapeutic response. Even with free treatment, households may suffer catastrophic health expenditure from direct and indirect medical costs, which compounds existing financial strain in low-income communities for households and healthcare systems. The dermatological presentations of the leishmaniases may result in long-term severe disfigurement, leading to stigmatization, reduced quality of life, discrimination and mental health issues. A substantial amount of recent literature points to the vulnerability pathways and burden of leishmaniasis on women, in particular, who disproportionately suffer from these impacts. These emerging foci demonstrate a need for continued international efforts to address key risk factors and population vulnerabilities if leishmaniasis control, and ultimately elimination, is to be achieved by 2030.

Economic evaluations addressing diagnosis and treatment strategies for neglected tropical diseases: an overview

Neglected tropical diseases (NTDs) are those affecting vulnerable people and causing additional social and economic burden. The aim of this study was to carry out a general overview of the health economic assessments involving the diagnosis and treatment of six NTDs: cutaneous leishmaniasis (CL), Chagas disease, cysticercosis, filariasis, schistosomiasis and visceral leishmaniasis (VL). The literature search was based on two of the main medical literature databases (Medline and SciELO) and identified 46 studies. Twenty-six studies (57%) addressed therapeutic strategies, while other 20 (43%) assessed diagnostic or both diagnostic and therapeutic approaches. The studies were published between 1994 and 2021, and 57% of them (26/46) were carried out in four countries. Cost-effectiveness analyses were conducted in 59% (27/46) of the studies. Economic studies of NTDs have timidly increased in recent years. Despite the improvement of analytical methods, completeness and accuracy of information, there are few new technologies applied to NTDs and public health systems. In addition, economic studies for NTDs are concentrated in a few countries. Thus, this review points out the need for investment in research, development and training of human resources dedicated to the economic analysis in health, especially on NTDs, as a strategy to reduce inequalities by optimizing the use of health resources.

Canine Visceral Leishmaniasis in an Area of Sporadic Transmission in Brazil

Canine visceral leishmaniasis is a zoonotic disease caused by the protozoan Leishmania infantum in Latin America. Visceral leishmaniasis (VL) diagnosis in Brazil includes two serological tests according to the Ministry of Health (MH) protocol. Sensitivity and specificity of diagnostic tests, as well as clinical signs of VL, are usually reported in disease-endemic areas; however, it is known that local epidemiological factors can influence these results. This study aimed to evaluate the clinical features, sensitivity, and specificity of TR-DPP^® and EIE-LVC in naturally infected dogs in a region of sporadic VL transmission to humans in Brazil. A total of 288 dogs were clinically evaluated and serological and parasitological (lymph node aspirates) samples were collected for VL diagnosis. TR-DPP and EIE-LVC showed poor sensitivity (0.62 and 0.44, respectively) to detect infected animals, compared with the direct parasitological examination, which is considered a gold standard method. Thus, the protocol of MH presented low sensitivity (0.42) to estimate prevalence and control measures in this region. TR-DPP presented a high negative predictive value (0.89), resulting in its indication as a confirmatory test in sporadic transmission areas. Classical clinical signs of VL were not frequently observed; therefore, clinical scoring systems might not be useful in this region. Veterinarians of nonendemic areas should be alert for asymptomatic dogs, especially those presenting lymph adenomegaly.

Estimating direct costs of the treatment for mucosal leishmaniasis in Brazil

INTRODUCTION

The objective of this study was to estimate the direct medical costs of the treatment for mucosal leishmaniasis (ML) using three therapeutic approaches in the Brazilian context.

METHODS

We performed this economic assessment from the perspective of the Brazilian public healthcare system. The following therapeutic approaches were evaluated: meglumine antimoniate, liposomal amphotericin B, and miltefosine. Direct medical costs were estimated considering four treatment components: a) drug, b) combined medical products, c) procedures, and d) complementary tests.

RESULTS

Treatment with meglumine antimoniate had the lowest average cost per patient (US$ 167.66), followed by miltefosine (US$ 259.92) in the outpatient treatment regimen. The average cost of treatment with liposomal amphotericin B was US$ 715.35 both in inpatient regimen. In all estimates, the drugs accounted for more than 60% of the total cost for each treatment approach.

CONCLUSIONS

These results demonstrate the marked differences in costs between the therapeutic alternatives for ML. In addition to efficacy rates and costs related to adverse events, our data have the potential to support a complete cost-effectiveness study in the future. Complete analyses comparing costs and benefits for interventions will assist health managers in choosing drugs for ML treatment in Brazil as well as in establishing effective public health policies.

Treatment With Liposomal Amphotericin B for All Confirmed Cases of Human Visceral Leishmaniasis in Brazil: A Budget Impact Analysis

OBJECTIVES

To estimate the budget impact of the expansion of liposomal amphotericin B use for all confirmed cases of visceral leishmaniasis (VL) in Brazil. Currently, the first-line medicine for VL treatment is meglumine antimoniate. Liposomal amphotericin B is indicated only for patients with a greater risk of severity by the disease.

METHODS

The analysis was performed from the perspective of the Brazilian public healthcare system over 3 years, considering the following 2 scenarios: the reference scenario with the current recommendations for VL treatment and the alternative scenario based on the use of liposomal amphotericin B for all patients. A diffusion rate of 60% was used in the first year, 80% in the second year, and 100% in the third year. The epidemiological parameters used in the analysis came from the Notifiable Diseases Information System and from a clinical trial that evaluated the efficacy and safety of medicines for the treatment of VL in the country. The costs were related to the treatment of VL and to hospital and outpatient care.

RESULTS

In the reference scenario, the total cost for treatment of the 3453 VL confirmed cases in 2014 was $1 447 611.75. The incremental budget impact with the use of liposomal amphotericin B for all the VL confirmed cases was $299 646.43 in the third year.

CONCLUSIONS

The analysis presented will support the decision process for the use and expansion of liposomal amphotericin B for all VL confirmed cases in Brazil.

Cost-effectiveness of serological tests for human visceral leishmaniasis in the Brazilian scenario

Human visceral leishmaniasis (VL) is a severe and potentially fatal parasitic disease if not correctly diagnosed and treated. Brazil is one of the three countries most endemic for VL and, like most countries affected by this disease, has a large budget constraint for the incorporation of new health technologies. Although different diagnostic tests for VL are currently available in the country, economic studies evaluating diagnostic kits are scarce. The objective of this study was to conduct a cost-effectiveness analysis of the nine available diagnostic tests for human VL in HIV-infected and uninfected patients in Brazil. The perspective of analysis was the Brazilian public health system, and the outcome of interest was "cases diagnosed correctly". The costs of the tests were estimated using the microcosting technique, and comparisons were performed with decision trees. Sensitivity analyses were explored applying variations in cost and effectiveness values. For VL diagnosis among HIV-uninfected patients, using blood samples for the rapid tests (RDTs), the noncommercial direct agglutination test (DAT-LPC) and IT-LEISH were cost-effective tests compared with the baseline OnSite test, but they presented different incremental cost-effectiveness ratios (ICER) of US$7.04 and US$ 205.40, respectively. Among HIV-infected patients, DAT-LPC was the most cost-effective diagnostic test. Comparisons among the tests with the same methodology, based on the low ICER values, revealed that IT-LEISH was the most cost-effective test among the RDTs and the Ridascreen Leishmania Ab among the ELISA tests. These results confirm that cost-effectiveness analyses can provide useful information to support the incorporation of new health technologies within a known scenario and willingness to pay threshold. It was observed that tests based on the same methodologies presented different cost-effectiveness ratios for the same group of patients and that different tests should be recommended for different patient groups. DAT-LPC was an important cost-effective strategy for all patients, requiring minimum laboratorial infrastructure, and IT-LEISH was the cost-effective test for VL screening in HIV-uninfected patients. IT-LEISH and DAT-LPC have complementary profiles and should both be provided by the Brazilian health system.

How much does it cost to prevent and control visceral leishmaniasis in Brazil? Comparing different measures in dogs

Visceral leishmaniasis (VL) is an important zoonosis in Brazil. Dogs are considered the main domestic reservoirs of the disease in the country; hence, control measures are focused on these reservoirs. Despite efforts to prevent and control VL, important reductions in disease prevalence and incidence have not been identified, stimulating the development and application of new strategies. The choice and implementation of new control strategies can benefit from the application of mathematical models that allow the simulation of different strategies in different scenarios. Selecting the best strategy to be implemented is also supported by cost-effectiveness studies. Here we used the results of a mathematical model in which scenarios, including isolated use of the vaccine and insecticide-impregnated collar (IIC), both at different coverage rates, were simulated to conduct a cost-effectiveness study. The costs were calculated for each scenario considering a simulation period of four years. Collar application in both infected and non-infected animals was the most cost-effective strategy. For example, to reduce the prevalence in humans and dogs by approximately 70%, the costs ranged from $250,000 and $550,000 for the IICs and vaccination, respectively. Even in the scenario with 40% loss/replacement of IICs, this measure was more advantageous in terms of cost-effectiveness than vaccination. If the vaccine were applied with culling of seropositive tested dogs, then the measure became more effective with a reduced cost compared with the vaccine alone. The use of the three first consecutive vaccine doses had the greatest impact on the cost of the vaccination strategy. The advantage of using IICs is that there is no need for a prior diagnosis, unlike vaccination, reducing costs and facilitating implementation. The present study aims to contribute to strategies to reduce hosts infected with VL by reducing public expenditure.

Information differences across spatial resolutions and scales for disease surveillance and analysis: The case of Visceral Leishmaniasis in Brazil

Nationwide disease surveillance at a high spatial resolution is desired for many infectious diseases, including Visceral Leishmaniasis. Statistical and mathematical models using data collected from surveillance activities often use a spatial resolution and scale either constrained by data availability or chosen arbitrarily. Sensitivity of model results to the choice of spatial resolution and scale is not, however, frequently evaluated. This study aims to determine if the choice of spatial resolution and scale are likely to impact statistical and mathematical analyses. Visceral Leishmaniasis in Brazil is used as a case study. Probabilistic characteristics of disease incidence, representing a likely outcome in a model, are compared across spatial resolutions and scales. Best fitting distributions were fit to annual incidence from 2004 to 2014 by municipality and by state. Best fits were defined as the distribution family and parameterization minimizing the sum of absolute error, evaluated through a simulated annealing algorithm. Gamma and Poisson distributions provided best fits for incidence, both among individual states and nationwide. Comparisons of distributions using Kullback-Leibler divergence shows that incidence by state and by municipality do not follow distributions that provide equivalent information. Few states with Gamma distributed incidence follow a distribution closely resembling that for national incidence. These results demonstrate empirically how choice of spatial resolution and scale can impact mathematical and statistical models.

LeishCare®: A Software Designed for the Management of Individuals with Leishmaniases

The aims of this study were to describe a smartphone app aimed at healthcare professionals who work in areas endemic for visceral and tegumentary leishmaniases, and to report the user's perception of the app in these areas. The software, called LeishCare^®, has the following features: data registration, image filter to record the evolution of skin lesions using photos, calculation of a score set to identify the risk of death from visceral leishmaniasis, and guides to the diseases. LeishCare^® was made available to healthcare professionals in endemic municipalities in Brazil, and the perception of potential users was evaluated at baseline and after 6 and 12 months. In the first meeting, 96 (94.1%) of the 102 professionals who knew the app reported positive expectations for its use. The installation of LeishCare^® on the individual device and the evaluation of user perception were completed at 6 months with 16 users and at 12 months with 20 users. More than 90% of the professionals evaluated in both assessments found the information of the app useful. The features related to the calculation of visceral leishmaniasis severity score, and the guides to leishmaniases were the most frequently accessed. Users reported competence gain attributed to the app for all items evaluated. In conclusion, LeishCare^® was found to be a promising tool to help healthcare professionals in endemic areas with leishmaniasis management.

A cross-sectional approach including dog owner characteristics as predictors of visceral leishmaniasis infection in dogs

BACKGROUND

Visceral leishmaniasis (VL) is relevant for human and animal public health. Several factors have been associated with the risk of Leishmania infantum infection in dogs. However, dog owner characteristics have been rarely explored.

OBJECTIVES

To estimate the prevalence and to identify the associated factors for VL infection including dog owners characteristics.

METHODS

A cross-sectional study was conducted including dogs from an endemic canine visceral leishmaniasis (CVL) region in the Federal District, Brazil. The infection was detected using parasitological, serological, and molecular methods. The associated factors were identified through Poisson regression modelling.

FINDINGS

The prevalence of infection was 26.25% [95% confidence interval (CI): 20.05 to 33.57]. The associated factors were: short coat prevalence ratio (PR) = 2.33 (95% CI: 1.02 to 5.22); presence of backyard with predominance of soil and/or vegetation PR = 4.15 (95% CI: 1.35 to 12.77); and highest gross family income score PR = 2.03 (95% CI: 1.16 to 3.54).

MAIN CONCLUSION

This is the first study that relates higher socioeconomic status of dog owners as an independent factor associated with higher prevalence of VL infection, along with other strongly associated factors related to receptive environment for phlebotomines. Our findings strengthen the need for exploration of the biological and behavioural bases linking dog owner characteristics to the risk of canine infection in prospective cohort studies.

B. Valadas SY, L. Sousa-Gomes M, Lauletta Lindoso JA, Cupolillo E, Ruiz-Postigo JA, Argaw D, Sanchez-Vazquez MJ. Premature deaths by visceral leishmaniasis in Brazil investigated through a cohort study: A challenging opportunity?

BACKGROUND

Visceral Leishmaniasis (VL) is the most severe form of leishmaniasis because it can lead to death. In the Americas, 96% of cases are in Brazil, and despite efforts, the fatality rate has increased in the past years. We analyzed deaths associated to VL in Brazil and investigated the factors that could influence on the timeliness of fatal outcome with emphasis on time (tStoD).

METHODOLOGY

The registered deaths by VL were sourced from the Brazilian National Notification System from 2007-2014. Through a retrospective cohort study, univariate and multivariable Cox proportional hazards model analysis were performed and investigated the factors that could influence the time (tStoD). These factors were analyzed through survival models.

RESULTS

Out of the 1,589 reported deaths, the median for onset of the symptoms and the case notification date (tStoN) is 25 days (10-61), and for date of case notification and death (tNotD) is 9 days (4-17). The time (tStoN) to event investigation for HIV non-infected individuals was 1.4 (1.16-1.68) greater than the HIV positive group. At the same time peri-urban and urban area were 0.83 (0.47-1.44) and 1.33 (1.16-1.52), respectively. The explorations revealed apparent differences between the time to event investigation (both for tStoN and tNotD) and the age at the onset of the symptoms. According to the tStoN the rate of notification is 1.73 times greater in patients under 5 years old at the onset of the clinical symptoms compared to older patients.

CONCLUSION

VL patients under 5 years old were diagnosed earlier and had shorter survival. It could mean that in younger population, although properly diagnosed, the fatality pattern might be related to the severity of the disease. Main host characteristics were evaluated, and age and co-infections seem to have an impact in the disease progression.

Treatment for human visceral leishmaniasis: a cost-effectiveness analysis for Brazil

OBJECTIVE

To estimate the cost-effectiveness of strategies for the treatment of VL in Brazil.

METHODS

Cost-effectiveness study comparing three therapeutic options: meglumine antimoniate (MA), liposomal amphotericin B (LAMB) and a combination of LAMB plus MA (LAMB plus MA), from public health system and societal perspectives. An analytical decision-making model was used to compare strategies for the following outcomes: early therapeutic failure avoided at 30 days, days of hospitalisation avoided and VL cure at 180 days. The efficacy and safety parameters of the drugs came from a randomised, open-label trial and the cost data came from a cost-of-illness study, both carried out in Brazil.

RESULTS

For all outcomes analysed, the LAMB strategy was more effective. The MA strategy was inferior to the LAMB plus MA strategy for the outcomes early therapeutic failure avoided and cure. When only LAMB and MA were compared from a societal perspective, a cost of US$ 278.56 was estimated for each additional early therapeutic failure avoided, a cost of US$ 26.88 for each additional day of hospitalisation avoided and a cost of US$ 89.88 for each additional case of cured VL, for the LAMB strategy vs. MA.

CONCLUSION

In Brazil, the LAMB strategy proved to be cost-effective for treating VL, considering a GDP per capita as the willingness-to-pay threshold, for all of the outcomes analysed in comparison to MA.

Activity and Cell-Death Pathway in Leishmania infantum Induced by Sugiol: Vectorization Using Yeast Cell Wall Particles Obtained From Saccharomyces cerevisiae

Visceral leishmaniasis, caused by Leishmania infantum, is a neglected tropical disease, to which efforts in the innovation of effective and affordable treatments remain limited, despite the rising incidence in several regions of the world. In this work, the antileishmanial effects of sugiol were investigated in vitro. This compound was isolated from the bark of Cupressus lusitanica and showed promising activity against L. infantum. In spite of the positive results, it is known that the compound is a poorly water-soluble diterpene molecule, which hinders further investigation, especially in preclinical animal studies. Thus, in an alternative delivery method, sugiol was entrapped in glucan-rich particles obtained from Saccharomyces cerevisiae yeast cell walls (YCWPs). To evaluate the activity of sugiol, the experiments were divided into two parts: (i) the in vitro investigation of antileishmanial activity of free sugiol against L. infantum promastigotes after 24, 48, and 72 h of treatment and (ii) the evaluation of antileishmanial activity of sugiol entrapped in glucan-rich particles against intracellular L. infantum amastigotes. Free sugiol induced the cell-death process in promastigotes, which was triggered by enhancing cytosolic calcium level and promoting the autophagy up to the first 24 h. Over time, the presence of autophagic vacuoles became rarer, especially after treatment with lower concentrations of sugiol, but other cellular events intensified, like ROS production, cell shrinkage, and phosphatidylserine exposure. Hyperpolarization of mitochondrial membrane potential was found at 72 h, induced by the mitochondria calcium uptake, causing an increase in ROS production and lipid peroxidation as a consequence. These events resulted in the cell death of promastigotes by secondary necrosis. Sugiol entrapped in glucan-rich particles was specifically recognized by dectin-1 receptor on the plasma membrane of macrophages, the main host cell of Leishmania spp. Electron micrographs revealed particles containing sugiol within the infected macrophages and these particles were active against the intracellular L. infantum amastigotes without affecting the host cell. Therefore, the YCWPs act like a Trojan horse to successfully deliver sugiol into the macrophage, presenting an interesting strategy to deliver water-insoluble drugs to parasitized cells.

Cost-effectiveness analysis of diagnostic-therapeutic strategies for visceral leishmaniasis in Brazil

INTRODUCTION

Visceral leishmaniasis (VL) is fatal if not diagnosed and treated. This study aimed to estimate the cost-effectiveness of diagnostic-therapeutic alternatives for VL in Brazil.

METHODS

A decision model estimated the life expectancy and costs of six diagnostic-therapeutic strategies.

RESULTS

IT LEISH + liposomal amphotericin B emerged the best option, presenting lower costs and higher effectiveness. DAT-LPC + liposomal amphotericin B showed an incremental cost-effectiveness ratio of US$ 326.31 per life year.

CONCLUSIONS

These findings indicate the feasibility of incorporating DAT and designating liposomal amphotericin B as the first-line drug for VL in Brazil.

The cost of a disease targeted for elimination in Brazil: the case of schistosomiasis mansoni

BACKGROUND

Schistosomiasis mansoni is a poverty-related parasitic infection that has a variety of clinical manifestations. We consider the disability and deaths caused by schistosomiasis unacceptable for a tool-ready disease. Its condition in Brazil warrants an analysis that will enable better understanding of the local health losses and contribute to the complex decision-making process.

OBJECTIVE

This study estimates the cost of schistosomiasis in Brazil in 2015.

METHODS

We conducted a cost of illness study of schistosomiasis mansoni in Brazil in 2015 based on a prevalence approach and from a societal perspective. The study included 26,499 schistosomiasis carriers, 397 hepatosplenic cases, 48 cases with the neurological form, 284 hospitalisations, and 11,368.26 years of life lost (YLL) of which 5,187 years are attributable to economically active age groups.

RESULTS

The total cost of schistosomiasis mansoni in Brazil was estimated to be US$ 41,7million in 2015 with 94.61% of this being indirect costs.

CONCLUSIONS

The economic burden of schistosomiasis mansoni in Brazil is high and results in the loss of productivity. Its persistence in Brazil is a challenge to public health and requires inter-sectorial interventions in areas such as indoor water supply, basic sanitation, and education.

Understanding the economic impact of leishmaniasis on households in endemic countries: a systematic review

INTRODUCTION

Leishmaniasis is a poverty-related disease that causes a significant socioeconomic burden to affected households. Visceral leishmaniasis is fatal if untreated, yet illness costs may lead to delays in accessing care. Skin manifestations of leishmaniasis cause a psychological burden and even longer treatment trajectories. The objective of this review is to evaluate illness costs associated with leishmaniasis across different settings (Asia, Africa, and Latin America) and the consequences to households. Areas covered: Through a systematic review of cost-of-illness studies, we documented the distribution of costs, the health-seeking behavior, and the consequences of leishmaniasis. We discuss the value of cost-of-illness studies for leishmaniasis. Expert commentary: Despite the free provision of diagnostics and treatment in the public health care sector, out-of-pocket payments remain substantial. There has been progress in addressing the economic burden of leishmaniasis, particularly through the elimination initiative in the Indian subcontinent. Though the illness cost is decreasing due to shorter treatment regimens and better access to care, the situation remains challenging in Africa. Improvement of control tools is critical. There is a need to update cost estimates to inform policy-making and ensure sustainable solutions to reduce financial barriers to leishmaniasis care, especially in pursuing universal health coverage.

Clustered Breeding Sites: Shelters for Vector-Borne Diseases

Here, the propagation of vector-borne diseases is modeled by using a probabilistic cellular automaton. Numerical simulations considering distinct spatial distributions and time variations of the vector abundance are performed, in order to investigate their impacts on the number of infected individuals of the host population. The main conclusion is as follows: in the clustered distributions, the prevalence is lower, but the eradication is more difficult to be achieved, as compared to homogeneous distributions. This result can be relevant in the implementation of preventive surveillance measures.