Food handlers: an important reservoir of protozoans and helminth parasites of public health importance / Manipuladores de alimentos: um importante reservatório de protozoários e helmintos parasitas de importância para a saúde pública

Food handlers plays a primary role in the transmission of pathogenically important protozoans and helminth parasites. This study was aimed to evaluate the prevalence of intestinal pathogenic protozoans and helminth parasites among food handlers in and around University of Malakand, Lower Dir, Pakistan. Stool samples were collected from 642 food handlers (all of male) in a cross-sectional study from January to November, 2017. Wet Mount Techniques and concentration methods by using salt and formol–ether solutions. Three hundred and eighty four cases (59.8%) were found infected with one more parasites. Most of the individuals were found infected with helminth (47.6%) as compared to intestinal protozoans (0.93%). Seventy two cases (11.2%) of the cases presented mixed infection with both intestinal protozoan and helminth parasites. The order of prevalence for intestinal helminth was Ancylostoma duodenale (n = 258, 40.1%), followed by Taeniasa ginata (n=96, 14.9%) Ascaris lumbricoides (n = 54, 8.40%) and Trichuris trichura (n=30, 4.60%). For intestinal protozoa, Entamoeba histolytica/dispar (n = 36, 5.64%) was the only protozoan detected. Mono-parasitism was higher than poly-parasitism. Family size income and education level were the factors significantly (P<0.05) associated in the parasites prevalence. Current research showed that IPIs are primarily the foodborne pathogens still an important public health problem in Pakistan. Effective control programs on parasitic diseases transfer and their associated factors are recommended.

Os manipuladores de alimentos desempenham um papel fundamental na transmissão de protozoários e helmintos parasitas patogenicamente importantes. Este estudo teve como objetivo avaliar a prevalência de protozoários patogênicos intestinais e helmintos parasitas entre manipuladores de alimentos na Universidade de Malakand, Lower Dir, Paquistão. Amostras de fezes foram coletadas de 642 manipuladores de alimentos (todos do sexo masculino) em um estudo transversal de janeiro a novembro de 2017. Técnicas de montagem úmida e métodos de concentração usando soluções de sal e formol-éter. Trezentos e oitenta e quatro casos (59,8%) foram encontrados infectados com mais um parasita. A maioria dos indivíduos foi encontrada infectada por helmintos (47,6%) em comparação com protozoários intestinais (0,93%). Setenta e dois casos (11,2%) dos casos apresentavam infecção mista com protozoários intestinais e helmintos parasitas. A ordem de prevalência de helmintos intestinais foi Ancylostoma duodenale (n = 258, 40,1%), seguido por Taeniasa ginata (n = 96, 14,9%) Ascaris lumbricoides (n = 54, 8,40%) e Trichuris trichura (n = 30, 4,60 %). Para protozoários intestinais, Entamoeba histolytica / dispar (n = 36, 5,64%) foi o único protozoário detectado. Monoparasitismo foi maior do que poliparasitismo. A renda familiar e o nível de escolaridade foram os fatores significativamente (P <0,05) associados na prevalência de parasitos. A pesquisa atual mostrou que os IPIs são principalmente os patógenos de origem alimentar, ainda um importante problema de saúde pública no Paquistão. Programas eficazes de controle da transferência de doenças parasitárias e seus fatores associados são recomendados.

Hippocampal Atrophy/Sclerosis Is Associated with Old, Calcified Parenchymal Brain Neurocysticercosis, But Not with More Recent, Viable Infections.

Magnetic resonance images from 197 patients with calcified neurocysticercosis (NCC), 38 with viable NCC and 197 NCC-free healthy rural villagers were evaluated to compare the frequency of hippocampal atrophy/sclerosis (HAS) across these populations. Scheltens' medial temporal atrophy scale was used for hippocampal rating. The median age of the 432 study participants was 46 years (interquartile range, 29-62 years), and 58% were women. Hippocampal atrophy/sclerosis was disclosed in 26.9% patients with calcified NCC, compared with 7.9% in patients with viable NCC and 8.1% in healthy rural villagers. After adjusting for age, gender, and history of epilepsy, hippocampal atrophy/sclerosis was more frequent in patients with calcified NCC than in those with viable cysts (RR, 3.60; 95% CI, 1.18- 0.99; P = 0.025) and healthy rural villagers (RR, 3.43; 95% CI, 1.94-6.06; P < 0.001), suggesting that hippocampal damage develops late in the course of this parasitic disease.

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.

ASCVac-1, a Multi-Peptide Chimeric Vaccine, Protects Mice Against Ascaris suum Infection.

Control of human ascariasis, the most prevalent neglected tropical disease globally affecting 450 million people, mostly relies on mass drug administration of anthelmintics. However, chemotherapy alone is not efficient due to the high re-infection rate for people who live in the endemic area. The development of a vaccine that reduces the intensity of infection and maintains lower morbidity should be the primary target for infection control. Previously, our group demonstrated that immunization with crude Ascaris antigens in mice induced an IgG-mediated protective response with significant worm reduction. Here, we aimed to develop a multipeptide chimera vaccine based on conserved B-cell epitopes predicted from 17 common helminth proteomes using a bioinformatics algorithm. More than 480 B-cell epitopes were identified that are conserved in all 17 helminths. The Ascaris-specific epitopes were selected based on their reactivity to the pooled sera of mice immunized with Ascaris crude antigens or infected three times with A. suum infective eggs. The top 35 peptides with the strongest reactivity to Ascaris immune serum were selected to construct a chimeric antigen connected in sequence based on conformation. This chimera, called ASCVac-1, was produced as a soluble recombinant protein in an Escherichia coli expression system and, formulated with MPLA, was used to immunize mice. Mice immunized with ASCVac-1/MPLA showed around 50% reduced larvae production in the lungs after being challenged with A. suum infective eggs, along with significantly reduced inflammation and lung tissue/function damage. The reduced parasite count and pathology in infected lungs were associated with strong Th2 immune responses characterized by the high titers of antigen-specific IgG and its subclasses (IgG1, IgG2a, and IgG3) in the sera and significantly increased IL-4, IL-5, IL-13 levels in lung tissues. The reduced IL-33 titers and stimulated eosinophils were also observed in lung tissues and may also contribute to the ASCVac-1-induced protection. Taken together, the preclinical trial with ASCVac-1 chimera in a mouse model demonstrated its significant vaccine efficacy associated with strong IgG-based Th2 responses, without IgE induction, thus reducing the risk of an allergic response. All results suggest that the multiepitope-based ASCVac-1 chimera is a promising vaccine candidate against Ascaris sp. infections.

Buruli ulcer: a new case definition for Victoria.

ABSTRACT: Laboratory-confirmed infection with Mycobacterium ulcerans is currently notifiable to health departments in several jurisdictions. Accurate surveillance is imperative to understanding current and emerging areas of endemicity and to facilitate research into a neglected tropical disease with poorly-understood transmission dynamics. The state of Victoria currently reports some of the highest numbers of M. ulcerans cases in the world each year, with 340 cases notified in 2018 (an incidence of 5.5 per 100,000 population). In May 2019, a group of clinical, laboratory and public health experts met to discuss a new case definition for the surveillance of M. ulcerans disease in Victoria, incorporating clinical and epidemiological elements. The new case definition supports important public health messaging and actions for residents and visitors to popular tourist areas in Victoria.

Malignant catarrhal fever: An emerging yet neglected disease in captive sika deer (Cervus nippon) herds in China.

Malignant catarrhal fever (MCF) is a fatal lymphoproliferative disease that represents a serious problem in the deer-rearing industry. To better understand an MCF-like disease that has emerged in northern China since 2015, we investigated ten cases by documenting clinical and epidemiological data and analysing causative agents and histopathological changes. In addition, a retrospective screen for Macavirus DNA and a questionnaire-based survey were conducted. Epizootic MCF in Chinese sika deer herds has emerged with a low morbidity of 3.8% (95% CI: 2.5%-5.1%) and a high mortality of 93.2% (95% CI: 86.6%-99.9%). The disease course varied from 3 to 12 days. Aetiologically, OvHV-2 was predominant in the MCFV, accounting for most MCF cases (21/23). In contrast, only two CpHV-2 isolates were phylogenetically closely related to CpHV-2. Diarrhoea and nasal discharges were the most frequent manifestations, although clinical signs varied in some cases. Pathologically typical lesions of haemorrhage, necrosis and lymphoid cell infiltration were readily observed in a variety of organs. Vasculitis caused by vascular and perivascular lymphoid cell infiltration was common. The retrospective survey suggested a low positive rate (3/275) of MCFV DNA in peripheral blood lymphocytes (PBL). The questionnaire-based survey suggested the disease was neglected by local veterinarians, who did not acknowledge the risk of co-rearing deer with reservoir species. Collectively, the emerging epizootic MCF in Chinese sika deer herds remains neglected, emphasizing the urgency of initiating full-field diagnoses and control strategies.

Multiple food-borne trematodiases with profound systemic involvement: a case report and literature review.

BACKGROUND: Food-borne trematodiases are an important group of neglected global diseases. Affected patients in regions with low prevalence usually experience delayed diagnosis, especially when presenting with atypical clinical symptoms. Here, we presented a rare case of a Chinese patient infected with three food-borne trematodiases. CASE PRESENTATION: A 42-year-old man presented with diarrhea, lower extremity edema, and symptoms of cardiac dysfunction. He had a history of intermittent consumption of raw freshwater fishes for 6-7 years. Upon evaluation, he had eosinophilia, anemia, intrahepatic bile duct dilatation and a growing space-occupying lesion in the left atrium. The patient underwent a cardiac surgery which revealed an endocardial hematoma due to mechanical injuries. Imaging investigations also revealed intracranial and pulmonary lesions. A total of three trematodiases were diagnosed based upon microscopic stool examination, from which eggs of Clonorchis sinensis, Heterophyidae and Echinostomatidae were identified. Deposition of Clonorchis sinensis eggs was also observed from ileocecal squash slides. The patient was successfully treated with three cycles of praziquantel. CONCLUSIONS: Food-borne trematodiases may present with systemic involvement. Patients with dietary history of high risk or atypical ingestions should be evaluated for parasitic infection, even in non-endemic areas.

Focal spleen lesions in visceral leishmaniasis, a neglected manifestation of a neglected disease: report of three cases and systematic review of literature.

BACKGROUND: The Mediterranean area is endemic for the zoonotic form of visceral leishmaniasis (VL) caused by Leishmania infantum, a species which has been recently associated with unexpected epidemiological and clinical features. METHOD: We report the result of a systematic review of the literature on VL unusually presenting with spleen focal lesions, including three previously unpublished cases. RESULTS: A total of 28 cases of VL with multiple spleen focal lesions were retrieved. Twenty-six (93%) were acquired in the Mediterranean area, where L. infantum is endemic. Thirteen cases were diagnosed in children, and the remaining 15 cases in middle-aged adults, of whom 9 were immunosuppressed. Four patients (14%) underwent diagnostic splenectomy, while the diagnosis was confirmed by less invasive techniques in the remaining patients. The most common radiological patterns were: multiple subcentimetric or centimetric spleen lesions (size ≤ 1 cm in 14 of 19 cases, 74%), hypoechoic at ultrasonography (25 of 26 cases, 99%) and hypodense at CT scan (9 of 10 cases, 90%). PET-CT (available for four patients) showed an intense FDG spleen uptake. MRI and contrast-enhanced ultrasonography, available for two and one cases each, showed complex patterns. CONCLUSIONS: VL must be added to the list of possible differential diagnosis of spleen focal lesions and health care provider awareness about this condition will avoid unnecessary invasive diagnostic procedures.

Unpacking the Pathogen Box-An Open Source Tool for Fighting Neglected Tropical Disease.

The Pathogen Box is a 400-strong collection of drug-like compounds, selected for their potential against several of the world's most important neglected tropical diseases, including trypanosomiasis, leishmaniasis, cryptosporidiosis, toxoplasmosis, filariasis, schistosomiasis, dengue virus and trichuriasis, in addition to malaria and tuberculosis. This library represents an ensemble of numerous successful drug discovery programmes from around the globe, aimed at providing a powerful resource to stimulate open source drug discovery for diseases threatening the most vulnerable communities in the world. This review seeks to provide an in-depth analysis of the literature pertaining to the compounds in the Pathogen Box, including structure-activity relationship highlights, mechanisms of action, related compounds with reported activity against different diseases, and, where appropriate, discussion on the known and putative targets of compounds, thereby providing context and increasing the accessibility of the Pathogen Box to the drug discovery community.

Metal Compounds against Neglected Tropical Diseases.

Many first-line treatments for neglected tropical diseases identified by the World Health Organization (WHO) are limited by one or more of the following: the development of drug resistance, toxicity, and side effects, lack of selectivity, narrow therapeutic indices, route of administration, and bioavailability. As such, there is an urgent need to develop viable alternatives to overcome these limitations. The following review provides an overview of all existing metal complexes studied and evaluates the status of these complexes on the respective disease of choice.

Could SUVmax be an auxiliary parameter in the clinical management of pulmonary hydatid disease?

OBJECTIVE: The aim of this study was to investigate the role of 18F-fluorodeoxyglucose positron emission tomography/computerized tomography (FDG-PET/CT) in the diagnosis and treatment of pulmonary hydatid disease and also compare the morphological characteristics of the lesions with SUVmax values and identify complicated disease. METHODS: Thirty-six patients with a diagnosis of pulmonary hydatid disease who underwent 18F-FDG PET/CT imaging were included in this retrospective study. The size of the lesions, morphological characteristics, accompanying parenchymal and pleural findings, SUVmax and HUmean values and FDG uptake in mediastinal lymph nodes were noted. The relationship between morphologic properties, SUVmax of the lesions and lymphatic FDG uptake was analysed. RESULTS: A total of 99 lesions of 36 patients were classified as solid (7.1%), cystic (53.5%), semisolid (20.2%) and cavitary (19.2%). Thirty-two of the lesions were encapsulated, 38 of the lesions had border irregularity. Accompanying consolidation was present in 10 cases, bronchial obstruction in 9, pleural thickening in 28 and effusion in 3. There was positive correlation between lesions HUmean and SUVmax values (r = 0.285). SUVmax values were significantly higher in lesions with irregular borders, solid or semisolid type and presence of consolidation, bronchial obstruction and pleural thickening. Also more lymphatic FDG uptake was detected in this group. CONCLUSION: Higher SUVmax values may be a useful parameter in the diagnosis of complicated pulmonary hydatid disease. FDG-PET may provide guidance for determining the priority of lesion for surgery in cases with multiple lesions and may be helpful to evaluate the response to medical treatment.

Rare case of neglected large sacral Chordoma in a young female treated by wide En bloc resection and Sacrectomy.

BACKGROUND: Sacral chordoma is a locally aggressive malignant tumour originating from ectopic notochordal cells. The natural history of sacral chordoma is a slow growing tumour arising at the midline of the lower sacrum that can invade the sacrum and progressively increase in size expanding cranially and anteriorly. Metastasis is very rare even when the tumour is large. Sacral chordoma affects males more than females and is more commonly found in middle age and elderly patients. CASE PRESENTATION: A 25 years old female had neglected an extremely large midline sacral mass for 2 years. On presentation to hospital, she had been bed bound for the past 2 years. The sacral mass was so large that it prevented her from lying down supine and sitting on the wheelchair comfortably. Clinical examination showed a 40 cm × 30 cm × 20 cm hard mass over the sacrum that involved both buttocks and the gluteal fold. Neurological exam of bilateral lower limb was normal. Computed Tomography Scan of the Pelvis showed a large destructive sacrococcygeal mass measuring 43 cm × 38 cm × 27 cm with extension into the presacral space resulting in anterior displacement of the rectum, urinary bladder and uterus; and posterior extension into the dorsal soft tissue with involvement of the gluteus, piriformis, and left erector spinae muscles. Biopsy taken confirmed Chordoma. This patient was managed by a multidisciplinary team in an Oncology referral centre. The patient had undergone Wide En Bloc Resection and Sacrectomy, a complex surgery that was associated with complications namely bleeding, surgical site infection and neurogenic bowel and bladder. Six months post operatively the patient was able to lie supine and sit on wheelchair comfortably. She required extensive rehabilitation to help her ambulate in future. CONCLUSION: This is a rare case of neglected sacral chordoma in a young female treated with Wide En Bloc Resection and Sacrectomy associated with complications of this complex surgery. Nevertheless, surgery is still worthwhile to improve the quality of life and to prevent complications secondary to prolonged immobilization. A multidisciplinary approach is ideal and team members need to be prepared to address the complications once they arise.

Quality Assurance and Quality Control in the Global Trachoma Mapping Project.

In collaboration with the health ministries that we serve and other partners, we set out to complete the multiple-country Global Trachoma Mapping Project. To maximize the accuracy and reliability of its outputs, we needed in-built, practical mechanisms for quality assurance and quality control. This article describes how those mechanisms were created and deployed. Using expert opinion, computer simulation, working groups, field trials, progressively accumulated in-project experience, and external evaluations, we developed 1) criteria for where and where not to undertake population-based prevalence surveys for trachoma; 2) three iterations of a standardized training and certification system for field teams; 3) a customized Android phone-based data collection app; 4) comprehensive support systems; and 5) a secure end-to-end pipeline for data upload, storage, cleaning by objective data managers, analysis, health ministry review and approval, and online display. We are now supporting peer-reviewed publication. Our experience shows that it is possible to quality control and quality assure prevalence surveys in such a way as to maximize comparability of prevalence estimates between countries and permit high-speed, high-fidelity data processing and storage, while protecting the interests of health ministries.