Chronic wounds in Sierra Leone: Searching for Buruli ulcer, a NTD caused by Mycobacterium ulcerans, at Masanga Hospital.

BACKGROUND: Chronic wounds pose a significant healthcare burden in low- and middle-income countries. Buruli ulcer (BU), caused by Mycobacterium ulcerans infection, causes wounds with high morbidity and financial burden. Although highly endemic in West and Central Africa, the presence of BU in Sierra Leone is not well described. This study aimed to confirm or exclude BU in suspected cases of chronic wounds presenting to Masanga Hospital, Sierra Leone. METHODOLOGY: Demographics, baseline clinical data, and quality of life scores were collected from patients with wounds suspected to be BU. Wound tissue samples were acquired and transported to the Swiss Tropical and Public Health Institute, Switzerland, for analysis to detect Mycobacterium ulcerans using qPCR, microscopic smear examination, and histopathology, as per World Health Organization (WHO) recommendations. FINDINGS: Twenty-one participants with wounds suspected to be BU were enrolled over 4-weeks (Feb-March 2019). Participants were predominantly young working males (62% male, 38% female, mean 35yrs, 90% employed in an occupation or as a student) with large, single, ulcerating wounds (mean diameter 9.4cm, 86% single wound) exclusively of the lower limbs (60% foot, 40% lower leg) present for a mean 15 months. The majority reported frequent exposure to water outdoors (76%). Self-reports of over-the-counter antibiotic use prior to presentation was high (81%), as was history of trauma (38%) and surgical interventions prior to enrolment (48%). Regarding laboratory investigation, all samples were negative for BU by microscopy, histopathology, and qPCR. Histopathology analysis revealed heavy bacterial load in many of the samples. The study had excellent participant recruitment, however follow-up proved difficult. CONCLUSIONS: BU was not confirmed as a cause of chronic ulceration in our cohort of suspected cases, as judged by laboratory analysis according to WHO standards. This does not exclude the presence of BU in the region, and the definitive cause of these treatment-resistance chronic wounds is uncertain.

Case Report: Successful Outcome of Primary Infertility with Multidrug Therapy in a Long-Standing Case of Hypogonadism Resulting from Lepromatous Leprosy: Shattering the Dogma of Irreversible Infertility in Leprosy.

We present a case of primary infertility with features of hypogonadism in a male patient with lepromatous leprosy who had remained undiagnosed for 3 years. On investigation, azoospermia and deranged gonadotropin levels with normal serum testosterone were noted and the patient was initiated on multibacillary-multidrug therapy with the primary aim of treating the disease. Although the cutaneous lesions improved within 6 weeks, remarkably infertility was reversed in 2 months-with concomitant normalization of luteinizing hormone, follicle stimulating hormone, and sperm count-an outcome that was unexpected. While reiterating leprosy as a cause of infertility, we discuss the probable mechanism for the efficacy of multidrug therapy in what seemed to be an irreversible outcome of advanced lepromatous leprosy.

An inexpensive point-of-care immunochromatographic test for Talaromyces marneffei infection based on the yeast phase specific monoclonal antibody 4D1 and Galanthus nivalis agglutinin.

Talaromyces marneffei is a thermally dimorphic fungus that causes opportunistic systemic mycoses in patients with AIDS or other immunodeficiency syndromes. The purpose of this study was to develop an immunochromatographic strip test (ICT) based on a solid phase sandwich format immunoassay for the detection of T. marneffei antigens in clinical urine specimens. The T. marneffei yeast phase specific monoclonal antibody 4D1 (MAb4D1) conjugated with colloidal gold nanoparticle was used as a specific signal reporter. Galanthus nivalis Agglutinin (GNA) was adsorbed onto nitrocellulose membrane to serve as the test line. Similarly, a control line was created above the test line by immobilization of rabbit anti-mouse IgG. The immobilized GNA served as capturing molecule and as non-immune mediated anti-terminal mannose of T. marneffei antigenic mannoprotein. The MAb4D1-GNA based ICT showed specific binding activity with yeast phase antigen of T. marneffei, and it did not react with other common pathogenic fungal antigens. The limit of detection of this ICT for T. marneffei antigen spiked in normal urine was approximately 0.6 µg/ml. The diagnostic performance of the ICT was validated using 341 urine samples from patents with culture- confirmed T. marneffei infection and from a control group of healthy individuals and patients with other infections in an endemic area. The ICT exhibited 89.47% sensitivity, 100% specificity, and 97.65% accuracy. Our results demonstrate that the urine-based GNA-MAb4D1 based ICT produces a visual result within 30 minutes and that the test is highly specific for the diagnosis of T. marneffei infection. The findings validate the deployment of the ICT for clinical use.

Rickettsial infections: A blind spot in our view of neglected tropical diseases.

Rickettsial diseases are a group of vector-borne bacterial infections that cause acute febrile illness with potentially severe or fatal complications. These vector-borne diseases are prevalent in tropical and subtropical regions worldwide and disproportionately affect poorer communities but are scientifically underrecognized. Despite this, they are not included in the World Health Organization's list of neglected tropical diseases nor were they mentioned in Peter Hotez's recent reflections on "What constitutes a neglected tropical disease?" in PLOS Neglected Tropical Diseases [1]. Here we present the case that rickettsial infections, as an overlooked cause of morbidity, mortality, and economic losses in marginalized populations, should be recognized as neglected tropical diseases. We describe how this oversight is the result of a number of factors and how it negatively impacts patient outcomes. We then propose measures to address the neglect of rickettsial infections in both scientific research and public health interventions.

The enigmatic biology of rickettsiae: recent advances, open questions and outlook.

Rickettsiae are obligate intracellular bacteria that can cause life-threatening illnesses and are among the oldest known vector-borne pathogens. Members of this genus are extraordinarily diverse and exhibit a broad host range. To establish intracellular infection, Rickettsia species undergo complex, multistep life cycles that are encoded by heavily streamlined genomes. As a result of reductive genome evolution, rickettsiae are exquisitely tailored to their host cell environment but cannot survive extracellularly. This host-cell dependence makes for a compelling system to uncover novel host-pathogen biology, but it has also hindered experimental progress. Consequently, the molecular details of rickettsial biology and pathogenesis remain poorly understood. With recent advances in molecular biology and genetics, the field is poised to start unraveling the molecular mechanisms of these host-pathogen interactions. Here, we review recent discoveries that have shed light on key aspects of rickettsial biology. These studies have revealed that rickettsiae subvert host cells using mechanisms that are distinct from other better-studied pathogens, underscoring the great potential of the Rickettsia genus for revealing novel biology. We also highlight several open questions as promising areas for future study and discuss the path toward solving the fundamental mysteries of this neglected and emerging human pathogen.

The development of a novel diagnostic PCR for Madurella mycetomatis using a comparative genome approach.

BACKGROUND: Eumycetoma is a neglected tropical disease most commonly caused by the fungus Madurella mycetomatis. Identification of eumycetoma causative agents can only be reliably performed by molecular identification, most commonly by species-specific PCR. The current M. mycetomatis specific PCR primers were recently discovered to cross-react with Madurella pseudomycetomatis. Here, we used a comparative genome approach to develop a new M. mycetomatis specific PCR for species identification. METHODOLOGY: Predicted-protein coding sequences unique to M. mycetomatis were first identified in BLASTCLUST based on E-value, size and presence of orthologues. Primers were then developed for 16 unique sequences and evaluated against 60 M. mycetomatis isolates and other eumycetoma causing agents including the Madurella sibling species. Out of the 16, only one was found to be specific to M. mycetomatis. CONCLUSION: We have discovered a predicted-protein coding sequence unique to M. mycetomatis and have developed a new species-specific PCR to be used as a novel diagnostic marker for M. mycetomatis.

The cycle of distrust in health policy and behavior: Lessons learned from the Negev Bedouin.

BACKGROUND: Over the last decades, health systems worldwide have faced a decline in public trust. For marginalized minority populations, who generally suffer from poverty and political exclusion, the roots of this trend go much deeper, establishing a state of bi-directional distrust between them and health institutions. Although studied to a lesser extent compared to trust, distrust does impede health initiatives, such as infectious diseases prevention programs, mostly of so-called Neglected Zoonotic Diseases (NZDs). Where distrust prevails, even trust building actions such as defining rights and obligations, prioritizing "the greater good" and increasing transparency, are prone to failure. In this study, we deepen the understanding of the concept of distrust through a unique case study of Brucellosis, a prevalent bacterial zoonotic disease endemic to disadvantaged Bedouin communities in southern Israel. METHODS: In the years 2015-2019, we qualitatively studied socio-political aspects in a governmental Brucellosis control campaign in southern Israel. We used in-depth interviews with 38 governmental and private health workers, agriculture and nature preservation workers, livestock owners and community leaders. Further, we conducted participant observation in 10 livestock pens and in policymaking meetings, and collected policy and media documents in order to triangulate the results. RESULTS: We conceptualize three different types of distrust between authorities and marginalized communities-"intention-based distrust", "values-based distrust" and "circular distrust"-to better explain how distrust originates and reinforces itself, reproducing the endemicity of NZDs. Based on that, we portray a practical framework to reduce distrust in health policies, by reframing local discourses, reshaping disease monitoring schemes from enforcement-based to participation-based, and promoting political inclusion of disadvantaged communities. CONCLUSIONS: The suggested analysis and framework redirect health policy objectives to not only acknowledge, contain and reduce the consequences of distrust, but also to strive for societal justice as a tool for health promotion.

Dual RNA-seq of Orientia tsutsugamushi informs on host-pathogen interactions for this neglected intracellular human pathogen.

Studying emerging or neglected pathogens is often challenging due to insufficient information and absence of genetic tools. Dual RNA-seq provides insights into host-pathogen interactions, and is particularly informative for intracellular organisms. Here we apply dual RNA-seq to Orientia tsutsugamushi (Ot), an obligate intracellular bacterium that causes the vector-borne human disease scrub typhus. Half the Ot genome is composed of repetitive DNA, and there is minimal collinearity in gene order between strains. Integrating RNA-seq, comparative genomics, proteomics, and machine learning to study the transcriptional architecture of Ot, we find evidence for wide-spread post-transcriptional antisense regulation. Comparing the host response to two clinical isolates, we identify distinct immune response networks for each strain, leading to predictions of relative virulence that are validated in a mouse infection model. Thus, dual RNA-seq can provide insight into the biology and host-pathogen interactions of a poorly characterized and genetically intractable organism such as Ot.

Soil-transmitted helminthiasis: A neglected tropical disease among urban slum dwelling school-aged children of a sub-Saharan African city.

BACKGROUND: The need to generate a robust epidemiological data on the neglected tropical diseases is imperative, in order to encourage access to formal care, drive public policies and ensure the allocation of resources by policy-makers. OBJECTIVES: The objective of this study was to determine the prevalence of soil-transmitted helminthiasis (STH) and its association with nutritional variables among primary school pupils living in urban slums in a South-Eastern sub-Saharan African city of Enugu, Nigeria. METHODS: The stool samples of school-aged children living in urban slums were analyzed for ova of the helminths using the Kato-Katz methods, whereas the nutritional assessment (weight and height) was obtained and analyzed to indicate acute or chronic malnutrition. Degrees of helminthic load were then classified. The socioeconomic status was determined while the prevalence of STH and the relationship between it and the nutritional stratus was assessed to ascertain any significance between being malnourished and having STH as this will inform policy decisions. RESULTS: There were a total of 371 analyzed stool samples from 228 females (61.5%) and 143 males (38.5%), with 285 (76.8%) from the lowest socioeconomic class. The prevalence of STH was 18.1%, while that of acute and chronic malnutrition were 3.3% and 7.5%, respectively. The intensity of infestation was, however, light, with the highest mean egg intensity of 74.4 ± 32.8 documented for ascariasis. There was no statistically significant association between the presence of STH and various indices of acute and chronic malnutrition (P > 0.05). CONCLUSION: STHs prevalence is high among children living in urban slums. Nutritional status was, however, not adversely affected by helminthic infestation.

Brucellosis in China: history, progress and challenge.

Brucellosis is a neglected zoonosis. It causes acute febrile illness and a potentially debilitating chronic infection in humans, and livestock infection has substantial socioeconomic impact. Over the past two decades, improvements have been made to better understand the various aspects of human and animal brucellosis. Meanwhile, especially in the developing world, immense challenges that remain in controlling and eradicating brucellosis are novel diagnostics tools and efficacious vaccines. Here, we will focus on the remarkable issues on epidemiological survey, as well as the priority and challenge of brucellosis in China. Brucellosis will be controlled with meaningful collaboration between local and public partnerships effectively applying a One Health framework.

Mycetoma in Uganda: A neglected tropical disease.

Mycetoma is considered a neglected tropical disease globally. However, data on its burden and the associated complications in Uganda are limited. Hence we aimed to estimate its burden in Uganda. Firstly, a systematic PubMed search for all studies of any design on mycetoma in Uganda without restriction to the year of publication was conducted. A retrospective review of all the biopsy reports at the Pathology Reference Laboratory, Department of Pathology, Makerere University, Kampala, Uganda from January 1950 to September 2019 was conducted to identify any reports on mycetoma histological diagnosis. During the 70-years study period, 30 cases were identified by the literature review, with 249 additional cases identified by review of biopsy reports (total of 279 cases). The average incidence was estimated at 0.32/100,000 persons and prevalence of 8.32/100,000 persons per decade. However, there was a general decline in the number of cases detected recently. Males and the age group of 21-30 years were the most affected by mycetoma in Uganda, and only 7% of the cases were children. The highest number of cases was recorded from Kampala (n = 30) and Jinja (n = 19) districts. The majority of the cases (68%) were referred from surgical units. The foot was the most affected part of the body (72%). Ten per cent of the cases had bone involvement of which 58% required amputation. Fungi were the most common causative agents (89%) followed by Nocardia species (5%) and Actinomycetes (4%). The index of clinical suspicion of mycetoma was low (45%) with a very large differential diagnosis. Mycetoma is a relatively rare disease in Uganda, mostly caused by fungi, and there is a big gap in data and epidemiological studies. More systematic studies are warranted to define the true burden of mycetoma in Uganda.

Integrated approach in the control and management of skin neglected tropical diseases in three health districts of Côte d'Ivoire.

BACKGROUND: Neglected tropical diseases (NTDs) comprise 20 communicable diseases that are prevalent in rural poor and remote communities with less access to the health system. For effective and efficient control, the WHO recommends that affected countries implement integrated control interventions that take into account the different co-endemic NTDs in the same community. However, implementing these integrated interventions involving several diseases with different etiologies, requiring different control approaches and driven by different vertical programs, remains a challenge. We report here the results and lessons learned from a pilot test of this integrated approach based on integrated screening of skin diseases in three co-endemic health districts of Côte d'Ivoire, a West African country endemic for Buruli ulcer, leprosy and yaw. METHOD: This cross-sectional study took place from April 2016 to March 2017 in 3 districts of Côte d'Ivoire co-endemic for BU, leprosy and yaws. The study was carried out in 6 stages: identification of potentially co-endemic communities; stakeholder training; social mobilization; mobile medical consultations; case detection and management; and a review meeting. RESULTS: We included in the study all patients with skin signs and symptoms at the screening stage who voluntarily accepted screening. In total, 2310 persons screened had skin lesions at the screening stage. Among them, 07 cases were diagnosed with Buruli ulcer. There were 30 leprosy cases and 15 yaws detected. Other types of ulcerations and skin conditions have been identified and represent the majority of cases detected. We learned from this pilot experience that integration can be successfully implemented in co-endemic communities in Côte d'Ivoire. Health workers are motivated and available to implement integrated interventions instead of interventions focused on a single disease. However, it is essential to provide capacity building, a minimum of drugs and consumables for the care of the patients identified, as well as follow-up of identified patients, including those with other skin conditions. CONCLUSIONS: The results of this study show that the integration of activities can be successfully implemented in co-endemic communities under the condition of staff capacity building and minimal care of identified patients.

Selection of Diagnostic Cutoffs for Murine Typhus IgM and IgG Immunofluorescence Assay: A Systematic Review.

Murine typhus is a neglected but widespread infectious disease that results in acute fever. The immunofluorescence assay (IFA) is the "gold standard" to identify IgM or IgG antibodies, although there is a lack of standardization in methodologies. The objective of this review is to summarize 1) the differences in published methodologies, 2) the diagnostic cutoff titers, and 3) the justification of diagnostic cutoffs. Searches were performed by combining the following search terms: "murine typhus," "rickettsia typhi," "immunofluorescence," "IFA," and "serologic" with restrictions (i.e., "rickettsia typhi" or "murine typhus," and "IFA" or "immunofluorescence," or "serologic*"). The search identified 78 studies that used IFA or immunoperoxidase assay (IIP) antibody cutoffs to diagnose murine typhus, 39 of which were case series. Overall, 45 studies (57.7%) provided little to no rationale as to how the cutoff was derived. Variation was seen locally in the cutoff titers used, but a 4-fold or greater increase was often applied. The cutoffs varied depending on the antibody target. No consensus was observed in establishing a cutoff, or for a single-value diagnostic cutoff. In conclusion, there is a lack of consensus in the establishment of a single-value cutoff. Further studies will need to be executed at each distinct geographic location to identify region-specific cutoffs, while also considering background antibody levels to distinguish between healthy and infected patients.

Thinking in paracoccidioidomycosis: a delayed diagnosis of a neglected tropical disease, case report and review of clinical reports and eco-epidemiologic data from Colombia since the 2000.

BACKGROUND: Paracoccidioidomycosis is a neglected tropical disease, endemic in several countries of South America including Colombia. We report a case of a patient with Chronic Multifocal Paracoccidioidomycosis with long-standing symptoms and a delayed diagnosis caused by several barriers to achieve it. We did a review of the papers published in Colombia about this disease, focusing in clinical data and eco-epidemiology with the finding of a lack of new information on this topic since the 2000 in our region. CASE PRESENTATION: We present a 54-year-old man, farmer in his youth, with a chronic ulcerated lesion in the lower lip similar to a lip carcinoma, a deforming lesion in the nose, and respiratory symptoms with emphysematous lung. Lip biopsy with silver methenamine stain revealed small and large budding yeasts that resembles a "mariner's wheel" confirming Chronic Multifocal Paracoccidioidomycosis. He was treated successfully but subsequently lost to follow up. CONCLUSIONS: It is very important to focus attention, reinforce the search and create networks for the study of neglected tropical diseases. The presented case illustrates a usual clinical presentation, but with a delayed diagnosis due to the difficulties that still occur in some regions like ours for the early recognition of a case of chronic multifocal paracoccidioidomycosis.

Leptospirosis: a neglected tropical zoonotic infection of public health importance-an updated review.

Leptospirosis is a zoonotic and waterborne disease worldwide. It is a neglected, reemerging disease of global public health importance with respect to morbidity and mortality both in humans and animals. Due to negligence, rapid, unplanned urbanization, and poor sanitation, leptospirosis emerges as a leading cause of acute febrile illness in many of the developing countries. Every individual has a risk of getting infected as domestic and wild animals carry leptospires; the at-risk population varies from the healthcare professionals, animal caretakers, farmers and agricultural workers, fishermen, rodent catchers, water sports people, National Disaster Response Force (NDRF) personnel, people who volunteer rescue operations in flood-affected areas, sanitary workers, sewage workers, etc. The clinical manifestations of leptospirosis range from flu-like illness to acute kidney failure (AKF), pneumonia, jaundice, pulmonary hemorrhages, etc. But many rare and uncommon clinical manifestations are being reported worldwide. This review will cover all possible updates in leptospirosis from occurrence, transmission, rare clinical manifestations, diagnosis, treatment, and prophylactic measures that are currently available, their advantages and the future perspectives, elaborately. There are less or very few reviews on leptospirosis in recent years. Thus, this work will serve as background knowledge for the current understanding of leptospirosis for researchers. This will provide a detailed analysis of leptospirosis and also help in finding research gaps and areas to focus on regarding future research perspectives.