Opportunities for Integrated Control of Neglected Tropical Diseases That Affect the Skin

Uncharted territory of the epidemiological burden of cutaneous leishmaniasis in sub-Saharan Africa-A systematic review

INTRODUCTION

Cutaneous leishmaniasis (CL) is the most frequent form of leishmaniasis, with 0.7 to 1.2 million cases per year globally. However, the burden of CL is poorly documented in some regions. We carried out this review to synthesize knowledge on the epidemiological burden of CL in sub-Saharan Africa.

METHODS

We systematically searched PubMed, CABI Global health, Africa Index Medicus databases for publications on CL and its burden. There were no restrictions on language/publication date. Case series with less than ten patients, species identification studies, reviews, non-human, and non-CL focused studies were excluded. Findings were extracted and described. The review was conducted following PRISMA guidelines; the protocol was registered in PROSPERO (42016036272).

RESULTS

From 289 identified records, 54 met eligibility criteria and were included in the synthesis. CL was reported from 13 of the 48 sub-Saharan African countries (3 eastern, nine western and one from southern Africa). More than half of the records (30/54; 56%) were from western Africa, notably Senegal, Burkina Faso and Mali. All studies were observational: 29 were descriptive case series (total 13,257 cases), and 24 followed a cross-sectional design. The majority (78%) of the studies were carried out before the year 2000. Forty-two studies mentioned the parasite species, but was either assumed or attributed on the historical account. Regional differences in clinical manifestations were reported. We found high variability across methodologies, leading to difficulties to compare or combine data. The prevalence in hospital settings among suspected cases ranged between 0.1 and 14.2%. At the community level, CL prevalence varied widely between studies. Outbreaks of thousands of cases occurred in Ethiopia, Ghana, and Sudan. Polymorphism of CL in HIV-infected people is a concern. Key information gaps in CL burden here include population-based CL prevalence/incidence, risk factors, and its socio-economic burden.

CONCLUSION

The evidence on CL epidemiology in sub-Saharan Africa is scanty. The CL frequency and severity are poorly identified. There is a need for population-based studies to define the CL burden better. Endemic countries should consider research and action to improve burden estimation and essential control measures including diagnosis and treatment capacity.

Feasibility and safety of mass drug coadministration with azithromycin and ivermectin for the control of neglected tropical diseases: a single-arm intervention trial

BACKGROUND

Mass drug administration has made a major contribution to the public health control of several important neglected tropical diseases. For settings with more than one endemic disease, combined mass drug administration has potential practical advantages compared with separate programmes but needs confirmation of feasibility and safety. We undertook a study of mass drug administration in the Solomon Islands for trachoma and scabies control using ivermectin and azithromycin, key drugs in the control of neglected tropical diseases worldwide.

METHODS

The entire population of Choiseul province, Solomon Islands, was eligible to participate. An azithromycin-based mass drug administration regimen was offered in line with standard recommendations for trachoma elimination (oral azithromycin or topical tetracycline). An ivermectin-based mass drug administration regimen was offered at the same time (oral ivermectin or topical permethrin), with a further dose 7-14 days later, using a modified version of a regimen demonstrated to be effective for scabies control. All participants underwent safety assessments 7-14 days later. Participants in ten randomly selected sentinel villages underwent a more detailed safety assessment. Routine health system reports of hospital or clinic admissions and deaths were also obtained to compare health outcomes in the 12 month period before and after the mass drug administration.

FINDINGS

The study enrolled 26 188 participants, 99·3% of the estimated resident population as determined at the 2009 census. Of those enrolled, 25 717 (98·2%) received the trachoma regimen and 25 819 (98·6%) received the first dose of the scabies regimen between Sept 1, and Oct 2, 2015. A second dose of the scabies regimen was received by 21 931 (83·7%) of participants. Adverse events, all mild and transient, were recorded in 571 (2·6%) of the entire study population and 58 (4·1%) of participants in the ten sentinel villages. In the 12 months before and after the mass drug administration the numbers of hospital admissions (1530 vs 1602) and deaths (73 vs 83) were similar. In the month after the mass drug administration, 84 individuals were admitted to hospital and two died, compared with a monthly median of 116 admissions (IQR 106-159) and six deaths (IQR 4-7) in the 12 months before and after the mass drug administration.

INTERPRETATION

In the largest trial so far involving coadministration of regimens based on ivermectin and azithromycin, the combination was safe and feasible in a population of more than 26 000 people. Coadministration of mass drug administration based on these two drugs opens up new potential for the control of neglected tropical diseases.

FUNDING

International Trachoma Initiative, Murdoch Children's Research Institute, Scobie and Claire Mackinnon Trust, Wellcome Trust.

The Skin-A Common Pathway for Integrating Diagnosis and Management of NTDs

Many of the neglected tropical diseases (NTDs) have major skin manifestations. These skin-related NTDs or ‘skin NTDs’ cause significant morbidity and economic hardship in some of the poorest communities worldwide. We draw attention to the collective burden of skin disease and suggest that the skin be used as a platform for the integration of control activities for NTDs. The opportunities for integration are numerous, ranging from diagnosis and disease mapping to mass drug administration and morbidity management. The dermatology community has an important role to play, and will be expected to support research and control activities globally.

Control Strategies for Scabies

Scabies is a neglected tropical disease of the skin, causing severe itching and stigmatizing skin lesions. Further, scabies leads to impetigo, severe bacterial infections, and post-infectious complications. Around 200 million people are affected, particularly among disadvantaged populations living in crowded conditions in tropical areas. After almost 50 years, research into scabies control has shown great promise, particularly in highly-endemic island settings, but these findings have not been widely adopted. Newer approaches, utilizing ivermectin-based mass drug administration, appear feasible and highly effective. Inclusion of scabies in the WHO portfolio of neglected tropical diseases in 2017 may facilitate renewed opportunities and momentum toward global control. However, further operational research is needed to develop evidence-based strategies for control in a range of settings, and monitor their impact. Several enabling factors are required for successful implementation, including availability of affordable drug supply. Integration with existing health programs may provide a cost-effective approach to control.

Integrated approach in the control and management of skin neglected tropical diseases in Lalo, Benin

BACKGROUND

Neglected Tropical Diseases (NTDs) are a group of several communicable diseases prevalent in the tropical and subtropical areas. The co-endemicity of these diseases, the similarity of the clinical signs, and need to maximize limited financial and human resources have necessitated implementation of integrated approach. Our study aims to share the lessons of this integrated approach in the fight against Buruli ulcer (BU), leprosy and yaws in a rural district in Benin.

METHODS

It is a cross-sectional study using a single set of activities data conducted from May 2016 to December 2016. Health workers and community health volunteers involved in this study were trained on integrated approach of the Buruli ulcer, leprosy and yaws. Village chiefs were briefed about the activity. The trained team visited the villages and schools in the district of Lalo in Benin. After the education and awareness raising sessions, all persons with a skin lesion who presented voluntarily to the team were carefully examined in a well-lit area which respected their privacy. Suspected cases were tested as needed. The socio-demographic information and the characteristics of the lesions were collected using a form. A descriptive analysis of the epidemiological, clinical and laboratory variables of the cases was made using Excel 2013 and SPSS version 22.00.

PRINCIPAL FINDINGS

In the study period, 1106 people were examined. The median (IQR) age of those examined was 11 (8; 27) years. Of 34 (3.1%) suspected BU cases, 15 (1.4%) were confirmed by PCR. Only three cases of leprosy were confirmed. The 185 (16.7%) suspected cases of yaws were all negative with the rapid test. The majority of cases were other skin conditions, including fungal infections, eczema and traumatic lesions.

CONCLUSION

The integrated approach of skin NTD allows optimal use of resources and surveillance of these diseases. Sustaining this skin NTD integrated control will require the training of peripheral health workers not only on skin NTD but also on basic dermatology.

Consensus criteria for the diagnosis of scabies: A Delphi study of international experts

Background

Scabies was added to the WHO Neglected Tropical Diseases portfolio in 2017, and further understanding of the disease burden is now required. There are no uniformly accepted test methods or examination procedures for diagnosis, which limits the interpretation of research and epidemiological findings. The International Alliance for the Control of Scabies (IACS) designated harmonization of diagnostic procedures as a priority for the development of a global control strategy. Therefore, we aimed to develop consensus criteria for the diagnosis of scabies.

Methodology / Principal findings

We conducted an iterative, consensus (Delphi) study involving international experts in the diagnosis of scabies. Panel members were recruited through expression of interest and targeted invitation of experts. The Delphi study consisted of four rounds of anonymous surveys. Rounds 1 and 2 involved generation and ranking an extensive list of possible features. In Rounds 3 and 4, participants were presented results from previous rounds and indicated agreement with a series of draft criteria. Panel participants (n = 34, range per Round 28–30) were predominantly highly experienced clinicians, representing a range of clinical expertise and all inhabited continents. Based on initial rounds, a draft set of criteria were developed, incorporating three levels of diagnostic certainty–Confirmed Scabies, Clinical Scabies and Suspected Scabies. Consensus was reached in Round 4, with a very high level of agreement (> 89%) for all levels of criteria and subcategories. Adoption of the criteria was supported by 96% of panel members.

Conclusions / Significance

Consensus criteria for scabies diagnosis were established with very high agreement. The 2018 IACS Criteria for the Diagnosis of Scabies can be implemented for scabies research and mapping projects, and for surveillance after control interventions. Validation of the criteria is required.

Scabies causes rash and severe itch and predisposes to serious infection and chronic diseases of the heart and kidneys. Despite scabies being an ancient disease found in all parts of the world, we currently lack reliable laboratory tests. Clinicians generally make an assessment based on history and skin examination. Variation in diagnosis causes problems when trying to determine the prevalence of scabies in a region, or when trying to investigate the effectiveness of a treatment or control strategy. We aimed to establish consensus among experts on how to diagnose scabies. Thirty-four international experts responded to anonymous questionnaires on how tests and clinical features of scabies should be used to form a diagnosis. Draft criteria were developed and refined, incorporating three levels of diagnostic certainty–Confirmed Scabies, Clinical Scabies and Suspected Scabies. After three rounds of surveys, 82% of participants supported the criteria. After four rounds, consensus was reached with very high agreement for all criteria (Confirmed Scabies, 96%; Clinical Scabies, 93%; Suspected Scabies, 100%) and 96% supported adoption of the criteria. It is hoped the 2018 IACS Criteria for the Diagnosis of Scabies will allow harmonization of diagnosis and reporting, and comparison between studies of scabies burden and treatments.

Skin disease prevalence study in schoolchildren in rural Côte d'Ivoire: Implications for integration of neglected skin diseases (skin NTDs)

Background

Early detection of several skin-related neglected tropical diseases (skin NTDs)–including leprosy, Buruli ulcer, yaws, and scabies- may be achieved through school surveys, but such an approach has seldom been tested systematically on a large scale in endemic countries. Additionally, a better understanding of the spectrum of skin diseases and the at-risk populations to be encountered during such surveys is necessary to facilitate the process.

Methods

We performed a school skin survey for selected NTDs and the spectrum of skin diseases, among primary schoolchildren aged 5 to 15 in Côte d’Ivoire, West Africa. This 2-phase survey took place in 49 schools from 16 villages in the Adzopé health district from November 2015 to January 2016. The first phase involved a rapid visual examination of the skin by local community healthcare workers (village nurses) to identify any skin abnormality. In a second phase, a specialized medical team including dermatologists performed a total skin examination of all screened students with any skin lesion and provided treatment where necessary.

Results

Of a total of 13,019 children, 3,504 screened positive for skin lesions and were listed for the next stage examination. The medical team examined 1,138 of these children. The overall prevalence of skin diseases was 25.6% (95% CI: 24.3–26.9%). The predominant diagnoses were fungal infections (n = 858, prevalence: 22.3%), followed by inflammatory skin diseases (n = 265, prevalence: 6.9%). Skin diseases were more common in boys and in children living along the main road with heavy traffic. One case of multi-bacillary type leprosy was detected early, along with 36 cases of scabies. Our survey was met with very good community acceptance.

Conclusion

We carried out the first large-scale integrated, two-phase pediatric multi-skin NTD survey in rural Côte d’Ivoire, effectively reaching a large population. We found a high prevalence of skin diseases in children, but only limited number of skin NTDs. With the lessons learned, we plan to expand the project to a wider area to further explore its potential to better integrate skin NTD screening in the public health agenda.

Integration of neglected tropical diseases (NTDs) into the public health agenda has been a priority in global health for the last decade. A common feature shared by several NTDs is skin involvement. Conditions within this group of NTDs have now been classified as skin NTDs to promote wider NTD integration. Several skin NTDs including leprosy, Buruli ulcer, yaws, and scabies are co-endemic in Côte d’Ivoire, West Africa. As children are vulnerable to these diseases, we carried out the first large-scale integrated, multi-skin NTD school survey in a rural district of this country. Our strategy of involving community healthcare workers and dermatologists effectively reached a large population. However, the detection of skin NTDs may have been limited because of the low schooling and attendance rate. We found a high prevalence of skin diseases among schoolchildren (26%), possibly due to poor socio-economic status and air pollution, which requires more attention. This high prevalence of skin diseases posed a challenge for our project as the need for medications and those with dermatological skills exceeded our capacity to reach our initial target population. Our study provides important lessons that will aid the framing of future school skin surveys in sub-Saharan Africa.

Implementation of a decentralized community-based treatment program to improve the management of Buruli ulcer in the Ouinhi district of Benin, West Africa

BACKGROUND

Mycobacterium ulcerans infection, commonly known as Buruli ulcer (BU), is a debilitating neglected tropical disease. Its management remains complex and has three main components: antibiotic treatment combining rifampicin and streptomycin for 56 days, wound dressings and skin grafts for large ulcerations, and physical therapy to prevent functional limitations after care. In Benin, BU patient care is being integrated into the government health system. In this paper, we report on an innovative pilot program designed to introduce BU decentralization in Ouinhi district, one of Benin's most endemic districts previously served by centralized hospital-based care.

METHODOLOGY/PRINCIPAL FINDINGS

We conducted intervention-oriented research implemented in four steps: baseline study, training of health district clinical staff, outreach education, outcome and impact assessments. Study results demonstrated that early BU lesions (71% of all detected cases) could be treated in the community following outreach education, and that most of the afflicted were willing to accept decentralized treatment. Ninety-three percent were successfully treated with antibiotics alone. The impact evaluation found that community confidence in decentralized BU care was greatly enhanced by clinic staff who came to be seen as having expertise in the care of most chronic wounds.

CONCLUSIONS/SIGNIFICANCE

This study documents a successful BU outreach and decentralized care program reaching early BU cases not previously treated by a proactive centralized BU program. The pilot program further demonstrates the added value of integrated wound management for NTD control.

How Can Elispot Add Information to Improve Knowledge on Tropical Diseases?

Elispot has been used as an important tool for detecting immune cells' products and functions and has facilitated the understanding of host-pathogen interaction. Despite the incredible diversity of possibilities, two main approaches have been developed: the immunopathogenesis and diagnosis/prognosis of infectious diseases as well as cancer research. Much has been described on the topics of allergy, autoimmune diseases, and HIV-Aids, however, Elispot can also be applied to other infectious diseases, mainly leishmaniasis, malaria, some viruses, helminths and mycosis usually classified as tropical diseases. The comprehension of the function, concentration and diversity of the immune response in the infectious disease is pointed out as crucial to the development of infection or disease in humans and animals. In this review we will describe the knowledge already obtained using Elispot as a method for accessing the profile of immune response as well as the recent advances in information about host-pathogen interaction in order to better understand the clinical outcome of a group of tropical and neglected diseases.

Ignoring the "Itch": The Global Health Problem of Scabies

Infestation with Sarcoptes scabiei var. hominis is a common human parasitic affliction endemic in tropical developing countries. Scabies is transmitted by close person-person contact, and outbreaks have been reported in reception centers for asylum seekers. Scabies presents clinically as extremely pruritic excoriated papules and linear burrows in the skin. This infestation predisposes to bacterial skin infections that can result in serious complications affecting the kidneys and possibly the heart. Treatment of individuals with scabies and their close contacts involves the use of antiparasitic agents. First-line treatment is topical 5% permethrin cream. Community mass drug administration, followed by active case finding with targeted treatment, is a promising approach that can reduce the prevalence of both scabies and bacterial skin infections. Organizations such as the International Alliance for the Control of Scabies are advocating for the development of integrated disease control strategies in an effort to decrease scabies infestation worldwide.

Neglected tropical diseases: exploring long term practical approaches to achieve sustainable disease elimination and beyond

Background

Remarkable progress has been made in the fight against neglected tropical diseases, but new challenges have emerged. Innovative diagnostics, better drugs and new insecticides are often identified as the priority; however, access to these new tools may not be sufficient to achieve and sustain disease elimination, if certain challenges and priorities are not considered.

Main body

The authors summarise key operational challenges, and based on these, identify two major priorities: strengthening the capacity of the primary health care health system in correctly diagnosing and managing neglected tropical diseases; and establishing an effective disease surveillance process.

Five steps are proposed as concrete actions to build an effective primary health care service for neglected tropical diseases, and a health management information system capable of accurately reporting these diseases. Community engagement and formalization of community health workers role are proposed as essential components of these steps.

Shift of financial support from disease oriented programmes to disease integrated interventions, improved access to international guidelines for primary health care staff, and availability of donated drugs in health care structures are also suggested as key elements of the proposed process.

Conclusion

The authors conclude that failure to address these priorities now may lead to further challenges on the long path towards neglected tropical disease elimination and beyond.

Electronic supplementary material

The online version of this article (doi: 10.1186/s40249-017-0361-8) contains supplementary material, which is available to authorized users.

The global burden of scabies: a cross-sectional analysis from the Global Burden of Disease Study 2015

BACKGROUND

Numerous population-based studies have documented high prevalence of scabies in overcrowded settings, particularly among children and in tropical regions. We provide an estimate of the global burden of scabies using data from the Global Burden of Disease (GBD) Study 2015.

METHODS

We identified scabies epidemiological data sources from an extensive literature search and hospital insurance data and analysed data sources with a Bayesian meta-regression modelling tool, DisMod-MR 2·1, to yield prevalence estimates. We combined prevalence estimates with a disability weight, measuring disfigurement, itch, and pain caused by scabies, to produce years lived with disability (YLDs). With an assumed zero mortality from scabies, YLDs were equivalent to disability-adjusted life-years (DALYs). We estimated DALYs for 195 countries divided into 21 world regions, in both sexes and 20 age groups, between 1990 and 2015.

FINDINGS

Scabies was responsible for 0·21% of DALYs from all conditions studied by GBD 2015 worldwide. The world regions of east Asia (age-standardised DALYs 136·32), southeast Asia (134·57), Oceania (120·34), tropical Latin America (99·94), and south Asia (69·41) had the greatest burden of DALYs from scabies. Mean percent change of DALY rate from 1990 to 2015 was less than 8% in all world regions, except North America, which had a 23·9% increase. The five individual countries with greatest scabies burden were Indonesia (age-standardised DALYs 153·86), China (138·25), Timor-Leste (136·67), Vanuatu (131·59), and Fiji (130·91). The largest standard deviations of age-standardised DALYs between the 20 age groups were observed in southeast Asia (60·1), Oceania (58·3), and east Asia (56·5), with the greatest DALY burdens in children, adolescents, and the elderly.

INTERPRETATION

The burden of scabies is greater in tropical regions, especially in children, adolescents, and elderly people. As a worldwide epidemiological assessment, GBD 2015 provides broad and frequently updated measures of scabies burden in terms of skin effects. These global data might help guide research protocols and prioritisation efforts and focus scabies treatment and control measures.

FUNDING

Bill & Melinda Gates Foundation.

Global Burden of Skin Disease: Inequities and Innovations

PURPOSE OF REVIEW

We review the current understanding of the burden of dermatological disease through the lens of the Global Burden of Disease project, evaluate the impact of skin disease on quality of life in a global context, explore socioeconomic implications, and finally summarize interventions towards improving quality of dermatologic care in resource-poor settings.

RECENT FINDINGS

The Global Burden of Disease project has shown that skin diseases continue to be the 4th leading cause of nonfatal disease burden world-wide. However, research efforts and funding do not match with the relative disability of skin diseases. International and national efforts, such as the WHO List of Essential Medicines, are critical towards reducing the socioeconomic burden of skin diseases and increasing access to care. Recent innovations such as teledermatology, point-of-care diagnostic tools, and task-shifting help to provide dermatological care to underserved regions in a cost-effective manner.

SUMMARY

Skin diseases cause significant non-fatal disability worldwide, especially in resource-poor regions. Greater impetus to study the burden of skin disease in low resource settings and policy efforts towards delivering high quality care are essential in improving the burden of skin diseases.

Gene silencing by RNA interference in Sarcoptes scabiei: a molecular tool to identify novel therapeutic targets

BACKGROUND

Scabies is one of the most common and widespread parasitic skin infections globally, affecting a large range of mammals including humans, yet the molecular biology of Sarcoptes scabiei is astonishingly understudied. Research has been hampered primarily due to the difficulty of sampling or culturing these obligatory parasitic mites. A further and major impediment to identify and functionally analyse potential therapeutic targets from the recently emerging molecular databases is the lack of appropriate molecular tools.

METHODS

We performed standard BLAST based searches of the existing S. scabiei genome databases using sequences of genes described to be involved in RNA interference in Drosophila and the mite model organism Tetranychus urticae. Experimenting with the S. scabiei mu-class glutathione S-transferase (SsGST-mu1) as a candidate gene we explored the feasibility of gene knockdown in S. scabiei by double-stranded RNA-interference (dsRNAi).

RESULTS

We provide here an analysis of the existing S. scabiei draft genomes, confirming the presence of a double stranded RNA (dsRNA) - mediated silencing machinery. We report for the first time experimental gene silencing by RNA interference (RNAi) in S. scabiei. Non-invasive immersion of S. scabiei in dsRNA encoding an S. scabiei glutathione S-transferase mu-class 1 enzyme (SsGST-mu1) resulted in a 35% reduction in the transcription of the target gene compared to controls.

CONCLUSIONS

A series of experiments identified the optimal conditions allowing systemic experimental RNAi without detrimental side effects on mite viability. This technique can now be used to address the key questions on the fundamental aspects of mite biology and pathogenesis, and to assess the potential therapeutic benefits of silencing S. scabiei target genes.

Yaws resurgence in Bankim, Cameroon: The relative effectiveness of different means of detection in rural communities

Background

Yaws is an infectious, debilitating and disfiguring disease of poverty that mainly affects children in rural communities in tropical areas. In Cameroon, mass-treatment campaigns carried out in the 1950s reduced yaws to such low levels that it was presumed the disease was eradicated. In 2010, an epidemiological study in Bankim Health District detected 29 cases of yaws. Five different means of detecting yaws in clinical and community settings were initiated in Bankim over the following five years.

Methodology

This observational study reviews data on the number of cases of yaws identified by each of the five yaws detection approaches: 1) passive yaws detection at local clinics after staff attended Neglected Tropical Disease awareness workshops, 2) community-based case detection carried out in remote communities by hospital staff who relied on community health workers to identify cases, 3) yaws screening following mass Buruli Ulcer outreach programs being piloted in the district, 4) school-based screening programs conducted as stand-alone and follow-up activities to mass outreach events, and 5) house to house active surveillance activities conducted in thirty-eight communities. Implementation of each of the four community-based approaches was observed by a team of health social scientists tasked with assessing the strengths and limitations of each detection method.

Findings

Eight hundred and fifteen cases of yaws were detected between 2012 and 2015. Only 7% were detected at local clinics. Small outreach programs and household surveys detected yaws in a broad spectrum of communities. The most successful means of yaws detection, accounting for over 70% of cases identified, were mass outreach programs and school based screenings in communities where yaws was detected.

Conclusion

The five interventions for detecting yaws had a synergistic effect and proved to be valuable components of a yaws eradication program. Well planned, culturally sensitive mass outreach educational programs accompanied by school-based programs proved to be particularly effective in Bankim. Including yaws detection in a Buruli Ulcer outreach program constituted a win-win situation, as the demonstration effect of yaws treatment (rapid cure) increased confidence in early Buruli ulcer treatment. Mass outreach programs functioned as magnets for both diseases as well as other kinds of chronic wounds that future outreach programs need to address.

Yaws is an infectious and disfiguring disease of poverty primarily affecting children in rural communities in tropical areas. Yaws is easily treated by a single dose of antibiotics and is on the World Health Organization’s eradication list. Yaws was thought eradicated in the Cameroon in the 1950s following aggressive mass-treatment campaigns. In 2010, epidemiological research revealed a resurgence of the disease. This paper discusses the relative success of five different means of detecting yaws in rural areas of Bankim District between 2012 and 2015. While few cases of yaws were detected at local clinics during this time, many cases were detected in the community. The most successful means of detecting yaws were mass outreach programs designed to educate the public about neglected tropical diseases found in the region, and follow up school-based screening programs. These programs were supported by local chiefs and traditional healers and found to be the best way of increasing community awareness about yaws, motivating community health workers to participate in outreach, and fostering trust in the free medical treatment being provided.

Treatment of Leishmania (Leishmania) Amazonensis-Infected Mice with a Combination of a Palladacycle Complex and Heat-Killed Propionibacterium acnes Triggers Protective Cellular Immune Responses

Palladacycle complex DPPE 1.2 was previously reported to inhibit the in vitro and in vivo infection by Leishmania (Leishmania) amazonensis. The aim of the present study was to compare the effect of DPPE 1.2, in association with heat-killed Propionibacterium acnes, on L. (L.) amazonensis infection in two mouse strains, BALB/c and C57BL/6, and to evaluate the immune responses of the treated animals. Foot lesions of L. (L.) amazonensis-infected mice were injected with DPPE 1.2 alone, or associated with P. acnes as an adjuvant. Analysis of T-cell populations in the treated mice and in untreated controls was performed by FACS. Detection of IFN-γ-secreting lymphocytes was carried out by an ELISPOT assay and active TGF-β was measured by means of a double-sandwich ELISA test. The treatment with DPPE 1.2 resulted in a significant reduction of foot lesion sizes and parasite burdens in both mouse strains, and the lowest parasite burden was found in mice treated with DPPE 1.2 plus P. acnes. Mice treated with DPPE 1.2 alone displayed a significant increase of TCD4⁺ and TCD8⁺ lymphocytes and IFN-γ secretion which were significantly higher in animals treated with DPPE 1.2 plus P. acnes. A significant reduction of active TGF-β was observed in mice treated with DPPE 1.2 alone or associated with P. acnes. Moreover, DPPE 1.2 associated to P. acnes was non-toxic to treated animals. The destruction of L. (L.) amazonensis by DPPE 1.2 was followed by host inflammatory responses which were exacerbated when the palladacycle complex was associated with P. acnes.