Tropical Parasitology最新文献

Background: Cystic echinococcosis (CE), caused by Echinococcus granulosus, is a major zoonotic disease that causes significant human morbidity and mortality. This cosmopolitan disease is difficult to diagnose, treat, and control. So far, crude extracts of hydatid cyst fluid containing antigen B or antigen 5 have been used as the primary antigenic source for its immunodiagnosis. The main issue is that it reacts with sera from people infected with other helminths. There is currently no standard, specific, or sensitive test for disease diagnosis, and no human vaccine has been reported.

Aims and objectives: Considering the need for efficient immunization and/or immunodiagnosis, six E. granulosus antigens, antigen 5, antigen B, heat shock proteins such as Hsp-8 and Hsp-90, phosphoenolpyruvate carboxykinase, and tetraspanin-1, were chosen.

Materials and methods: Using various in silico tools, T cell and B cell epitopes (promiscuous peptides) were predicted by targeting antigen 5, antigen B, heat shock proteins such as Hsp-8 and Hsp-90, phosphoenolpyruvate carboxykinase, and tetraspanin-1.

Results: There are twelve promiscuous peptides with overlapping human leukocyte antigen (HLA) class-I, class-II, and conformational B cell epitopes. Such immunodominant peptides could be useful as subunit vaccines. Furthermore, six peptides specific for E. granulosus were also discovered, which may prove to be important markers in the diagnosis of CE, potentially preventing misdiagnosis and mismanagement.

Conclusion: These epitopes may be the most important vaccine targets in E. granulosus because they have the most promiscuous peptides and B cell epitopes, as well as the highest affinity for different alleles, as determined by docking scores. However, additional research using in vitro and in vivo models is undertaken.

The free-living amebae of genus Acanthamoeba are an important cause of microbial keratitis. The clinical appearance of Acanthamoeba keratitis (AK) usually mimics viral or fungal keratitis. Thus, microbiological workup plays a significant role in the diagnosis and timely treatment of such cases. We report a retrospective case series of seven culture-confirmed AK cases from a tertiary eye care center in North India. Various risk factors and triggers of infection, clinical presentations, microbiological findings, and management of AK are elucidated.

Context: Amebic liver abscess (ALA) occurs in 3%-9% of the amebiasis cases, with complications seen in 20%-40% of the cases and 2%-18% mortality rate. Successful treatment thus requires the accurate identification of these cases.

Aims and objectives: We aimed to assess the seropositivity and profile of ALA patients in western Rajasthan.

Materials and methods: This retrospective study was conducted at a tertiary care center in western Rajasthan from November 2017 to May 2019. Serological diagnosis of ALA was done by detecting immunoglobulin G (IgG) antibodies in the serum of the patients by ELISA. The derangements in laboratory profile (hematological and biochemical parameters) and ultrasonography findings were assessed from the hospital records. Statistical analysis was performed using Mann-Whitney U-test.

Results: Among the total cases (n = 34), 20 were diagnosed as ALA. Twenty-one (61.8%) were positive for anti-amebic IgG antibodies. Among ALA patients, 14 (70%) were >40 years old and only 6 (30%) patients were of age ≤40 years. Male: female ratio was 5.7:1, and ultrasonography records of 15 ALA patients revealed the presence of hepatomegaly (n = 7, 46.7%), pleural effusion (n = 3, 20%), lung collapse (n = 2, 13.3%), and vascular involvement (n = 1, 6.7%). The right lobe of the liver was involved in majority of the patients (n = 12, 80%). Total white blood cell count (P < 0.001), absolute neutrophil count (P = 0.001), total serum bilirubin (P = 0.019), and serum alkaline phosphatase (P = 0.018) were significantly elevated in ALA patients.

Conclusions: Seroprevalence shows that ALA still remains the dominant etiology in liver abscess patients in this region. There are significant derangements in the laboratory profile that require a larger study for corroboration.

Introduction: Housefly (Musca domestica), because of its body structure, filthy and feeding habits, is reported to be capable of carrying a variety of microbes, including potential pathogens, over its body appendages.

Aims: This study aimed to investigate M. domestica in Calabar for pathogenic gut parasites, determine its role in parasitic diseases transmission, make appropriate recommendations toward its management and effective control of the associated parasitic diseases, and hence promote the society health status.

Settings and design: This was a cross-sectional study.

Materials and methods: A total of 300 M. domestica specimens (150 each from sanitary and insanitary areas, pooled in batches of five flies per pool) were used for the study. The parasites were detected from the spun deposits of fly body surface wash and gut contents using direct microscopy and formol-ether technique.

Statistical analysis used: Data were analyzed using Statistical Package for the Social Sciences (SPSS), version 21.0, and Chi-square test at a significant level of P < 0.05.

Results: Overall frequency of parasites detection was 46.7%, with helminths and protozoa showing similar frequency, 23.3% each. External body surface of flies recorded a statistically significant higher parasites frequency 76.7% than their gut contents 16.7% (P = 0.000). A statistically significant higher parasite detection rate was observed in the insanitary (63.3%) than in sanitary areas (30.0%) (P = 0.0114). The parasites detected in this study were Entamoeba histolytica/dispar 39.9%, hookworm (21.4%), Ascaris lumbricoides (17.9%), Trichuris trichiura (14.3%), and Giardia intestinalis (7.2%).

Conclusion: This study has confirmed M. domestica in Calabar as a mechanical carrier of potential pathogenic gut parasites, especially in the insanitary areas, with E. histolytica/dispar being the most frequently encountered. Effective control of flies' population in the human and animal habitats and increased public awareness on their health hazards are recommended.

Background: Despite the target of elimination of lymphatic filariasis by 2015, a few districts of West Bengal including Bankura district failed to achieve it. Under-coverage and unsupervised consumption of medicines during mass drug administration (MDA) campaign were implicated for the failure. Thereby, directly observed therapy (DOT) and mop up by repeated home visits for MDA were adopted.

Objective: The objective of this study is to assess the coverage of anti-filarial medicines distribution and rate of consumption as well as to find out the causes of nonconsumption.

Materials and methods: A cross-sectional survey was conducted in three sub-centers each of three blocks and three wards of Bankura municipality of Bankura district, WB, India, selected through the stratified random sampling method. Information was collected interviewing inhabitants of the house hold selected through the systematic random sampling technique.

Results: Overall, appropriate medicine distribution was 82.9% with 95.3% of correct consumption of both medicines under supervision. 91.87% of the respondents were aware about Lymphatic filariasis (LF) of which 89.95% reported swelling of leg/foot/hand, 9.57% as pain, 6.22% fever, and 1.44% reported swelling of testis as symptoms of LF. Altogether 10.6% individual, who consumed any medicine (527), reported AEs, out of that 66.1%, 19.6%, and 14.3% complained of dizziness/headache, nausea/vomiting, and drowsiness, respectively, and 28.6% of them sought consultation with health workers.

Conclusion: Substantial supervised consumption in the form DOT in this round too leads to the fact that the effective coverage of MDA has reached the target. It seemed that some segment of the beneficiary is remaining as persistent noncomplaints. Mass mobilization for motivating this persistent defaulter section is the need of the hour.

Background: Plants are an important option in the treatment of malaria, especially in endemic regions, and are a less expensive and more accessible alternative with a lower risk of toxicity. Colombia has a great diversity of plants, and evaluation of natural extracts could result in the discovery of new compounds for the development of antimalarial drugs. The purpose of this work was to evaluate the in vitro antiplasmodial activity and the cytotoxicity of plant extracts from the Colombian North Coast against Plasmodium falciparum.

Materials and methods: The antiplasmodial activity of 12 plant species from the Colombian North Coast that are used in traditional medicine was evaluated through in vitro cultures of P. falciparum, and the cytotoxicity of extracts of these species to human cells was determined. Plant extracts with high antiplasmodial activity were subjected to preliminary phytochemical screening.

Results: Extracts from five plants had promising antiplasmodial activity. Specifically, Bursera simaruba (Burseraceae) (bark), Guazuma ulmifolia Lam. (Malvaceae) (whole plant), Murraya exotica L. (Rutaceae) (leaves), Hippomane mancinella L. (Euphorbiaceae) (seeds), and Capparis odoratissima Jacq. (Capparaceae) (leaves). Extracts presented 50% inhibitory concentration values between 1 and 9 μg/ml. Compared to no extract, these active plant extracts did not show cytotoxic effects on mononuclear cells or hemolytic activity in healthy human erythrocytes.

Conclusions: The results obtained from this in vitro study of antiplasmodial activity suggest that active plant extracts from the Colombian North Coast are promising for future bioassay-guided fractionation to allow the isolation of active compounds and to elucidate their mechanism of action against Plasmodium spp.