Journal of Parasitology Research最新文献

Background: Malaria is a deadly vector-borne parasitic disease spread by the bite of an infective female Anopheles mosquito. In routine malaria diagnosis, microscopic examination is generally regarded as the gold standard. Our study sought to evaluate the diagnostic precision of two commercially accessible quantitative PCR (qPCR) kits, in contrast to light microscopy and nested multiplex PCR (NM-PCR). Methods: This cross-sectional study in southwest Saudi Arabia included 92 febrile patients meeting the inclusion criteria. Detection of Plasmodium species used light microscopy, NM-PCR, and qPCR kits (RealStar and Viasure). Sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and receiver operating characteristic (ROC) curves were calculated. Statistical analysis was performed using SPSS v25, with significance set at p ≤ 0.05. Results: Light microscopy detected 92.4% of cases, NM-PCR detected 73.9%, and RealStar and Viasure detected 92.4% and 95.7%, respectively. Viasure showed the highest sensitivity (97.6%) and NPV (50%), while NM-PCR had superior specificity (71.4%). For species identification, Plasmodium falciparum detection was highest with RealStar (85%). Mixed infections were better identified by Viasure (34.6%). RealStar excelled in Plasmodium vivax detection (area under the curve [AUC] = 90%). qPCR detected low parasitemia levels missed by microscopy. Conclusions: The qPCR kits, particularly Viasure, demonstrated superior sensitivity for detecting Plasmodium species and identifying mixed infections compared to light microscopy and NM-PCR. While light microscopy showed higher specificity and PPV, qPCR effectively detected low parasitemia levels missed by microscopy, highlighting its value in improving malaria diagnostics.

Cystic echinococcosis (CE) is a neglected parasitic infection with a particular impact in humans and livestock. The current investigation was undertaken to design and evaluate a DNA vaccine encoding Echinococcus granulosus Eg95-1 to EG95-6, P29, and GST against hydatid cyst infection in BALB/c mice. Initially, B-cell, cytotoxic T-lymphocyte, and helper T-lymphocyte epitopes were forecasted using B-cell epitope prediction server (BCPREDS) and Immune Epitope Database (IEDB) server, respectively, and a vaccine construct incorporating multiple epitopes was rationally designed and comprehensively analyzed through in silico modeling and simulation studies. Next, Escherichia coli TOP10 was transformed by the recombinant pcDNA 3.1 plasmid and mass production, followed by plasmid extraction, was done. The BALB/c mouse immunization was done with 50 and 100 μg concentrations of plasmid combined with IL-12 adjuvant or alone. Mouse sera and splenic lymphocytes were used for the measurement of specific humoral and cellular responses. The candidate vaccine model weighed 37.49 kDa with 338 residues antigenic, while nonallergenic, soluble, stable, highly thermotolerant, and hydrophilic in nature. Expression in HEK-293 cells was successfully achieved, as evidenced by the detection of a 37 kDa protein band in the western blot analysis. Vaccine doses, especially the 100 μg concentration, alone or in combination with an adjuvant, induced a T-helper 1 (Th1)-type immune response. This was evidenced by higher levels of IgG2a antibody and interferon gamma (IFN-γ) along with lower levels of interleukin 4 (IL-4). Although the groups that received the 50-μg dose of vaccine alone or with adjuvant showed a lower immune response, overall, the vaccinated groups showed statistically significant differences compared to the control groups (phosphate-buffered saline (PBS) and pcDNA). The promising results of this vaccine candidate can be further examined using challenges with various parasite genotypes.

Essential oils (EOs) have gained significant attention for their biopesticidal properties in pest management. This study investigates the insecticidal potential of EOs extracted from the aerial parts of three indigenous Artemisia species-Artemisia absinthium, Artemisia arborescens, and Artemisia campestris-collected from various provenances in Morocco. The EOs were tested individually and in combination against Culex pipiens (C. pipiens) larvae to explore potential synergistic interactions using a mixture design methodology. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography with flame ionization detection (GC-FID) analyses revealed quantitative and qualitative variations in the chemical composition of the oils. The primary constituents of A. absinthium were identified as thujone (32.20% ± 2.65%), camphor (19.95% ± 2.64%), and chamazulene (19.58% ± 2.33%). In A. arborescens, thujone (52.05% ± 3.84%), camphor (10.71% ± 3.08%), and eucalyptol (4.79% ± 1.53%) were the major components, while A. campestris comprised camphor (18.98% ± 2.65%), car-3-en-5-one (11.25% ± 2.33%), and thujone (6.63% ± 1.67%). When applied individually, all three EOs exhibited significant larvicidal activity against C. pipiens larvae, with A. arborescens showing the highest efficacy (LC₅₀ 11.11 μg/mL (5.45 ± 22.62)) compared to A. absinthium (LC₅₀: 16.98 μg/mL (6.73 ± 27.39)) and A. campestris (LC₅₀: 19.07 μg/mL (13.57 ± 23.38)). In mixture experiments, the mixture design outcomes reveal that the ternary formulation comprising 58% A. absinthium, 26% A. arborescens, and 16% A. campestris emerged as the most effective blend, achieving complete larval eradication. This study highlights the potential of Artemisia EO combinations as a sustainable and effective alternative for managing mosquito vectors of disease.

Hookworm infections present a major health risk to dogs, especially in areas characterized by warmer climates and poor sanitation. This cross-sectional study was undertaken to determine the prevalence of hookworm infections and the efficacy of anthelmintic treatments in dogs from the Bono East Region of Ghana. Four hundred and ninety-one (491) canine stool samples were examined using the McMaster technique to ascertain the prevalence of hookworms. Using in vivo and in vitro techniques, the efficacy of three anthelmintics (albendazole, pyrantel, and niclosamide) was assessed in an experimental control trial involving dogs naturally infected with hookworms. The effects of the drugs on hematological and biochemical parameters were measured within a 14-day period to assess changes over time. The study found a total prevalence of 54.2% (266), with significantly higher infection rates in puppies (69.8%, 97), hunting dogs (64.1%, 91), and rural dogs (84.2%, 160). Logistic regression identified age, purpose, and settlement type as risk factors for infection. Of the three treatments, niclosamide was the most efficacious, reducing egg counts by 95%, while albendazole was the least efficacious (-69%). In vitro tests confirmed the superior performance of niclosamide, with the lowest IC₅₀ value of 29.19 μg/mL. Hookworm-infected dogs exhibited anemia, eosinophilia, hypoalbuminemia, and hypoproteinemia. There was significant improvement in the hematobiochemical parameters after treatment, particularly in niclosamide-treated dogs. Veterinarians can consider niclosamide, especially in resource-limited settings, due to its affordability. The findings emphasize the importance of regular monitoring and treatment of hookworm infections to improve the overall health and well-being of dogs in the region. Herein, we report for the first time on reduced efficacy of albendazole and pyrantel against dog-related hookworms in Ghana.

Most Acanthamoebas contain endosymbionts such as viruses, yeasts, protists, and bacteria, some of which are potential human pathogens, including Campylobacter jejuni which often causes gastroenteritis and septicemia in humans. Amoebae have been shown to be resistant to chlorination and apparently protect ingested bacteria such as C. jejuni from free chlorine. Such resistance can have health implications, especially for drinking water treatment. The aim of this study is to identify Acanthamoeba in hospital samples in Markazi province, to determine the identity of C. jejuni endosymbiont in positive samples of Acanthamoeba in natural and laboratory conditions, and to determine the relationship between the two. The main aim of this study was to determine the identity of C. jejuni endosymbiont in Acanthamoeba-positive samples in natural and laboratory conditions. In this study, 134 samples including water, soil, and dust were collected from hospital environments. After molecular detection, the identity of the symbiotic Campylobacter jejuni in Acanthamoeba was determined by microscopic and PCR methods. Then, the ability of bacteria to infect the parasite was examined by cocultivation in vitro using real-time PCR. Finally, their relationship was examined based on statistical tests. The rate of contamination of hospital samples with Acanthamoeba was 44.7% on average. Out of 42 Acanthamoeba PCR-positive samples, seven isolates (16.67%) were found to be positive in terms of C. jejuni endosymbiont according to sampling location. The results showed that Helicobacter is able to penetrate and enter the Acanthamoeba parasite. In conclusion, our results showed that C. jejuni is able to contaminate Acanthamoeba in natural and laboratory conditions. The presence of pathogenic Acanthamoeba in various hospital environments and the hiding of Helicobacter as an endosymbiont inside it can pose a serious threat to the health of hospitalized patients.

Africa was home to 95% of malaria cases and deaths in 2021. The negative impacts of malaria can be aggravated by social-economic-environmental factors, more so agroeconomic practices such as irrigation, mining, and dam construction. The aim of this study was to investigate the impact of water harvesting, sugarcane farming, and mining activities on Plasmodium falciparum positivity rates and parasitemia densities in five selected sites in Msambweni Subcounty, Kwale Kenya. A cross-sectional concurrent mixed methods study was used to collect data. Kwale County was selected due to the high malaria endemicity possibly attributable to the suitable vector habitat characterized by the major anthropogenic activities. The study had five different arms of investigation; the first arm was the control (C), second dam (D) site, third sugarcane (S) site, fourth mining (M) site, and fifth dam-sugarcane-mining (DMS) site. Each of the 1025 consenting participants from 208 households provided a single blood sample for determining malaria prevalence and parasitemia using rapid diagnostic kit and microscopy. Overall, the malaria positivity rate was 22.9% by rapid diagnostic testing (RDT) and 20.1% by microscopy. P. falciparum observation by RDT was highest in the DMS site with 33.7% followed by S site with 26.8%, D site with 23.3%, and M site with 17.6%, and the least was the C site with 11.0%. The overall parasitemia density (parasite counts per 200 white blood cells) was 8.4 with a site-specific density of 18.7, 8.6, 7.1, 3.7, and 3.1 for DMS, S, D, M, and C sites, respectively. Univariable analysis of factors associated with malaria infection showed that participants in the DMS site were four times more likely to be infected with malaria (odds ratio (OR) = 4.1, p < 0.001) compared to those in the C site. Malaria vector and human host interactions are often enhanced by suitable environmental conditions especially ambient temperature which accelerate parasite growth in the mosquito and humidity. Anthropogenic activities may open up new breeding sites for the vector or increase human-Anopheles infective contact hours, hence the different positivity rates and intensities in P. falciparum transmission. The study results showed that prevalence of malaria and parasitemia was highest in areas where all the three anthropogenic activities were taking place. In the single-activity site, sugarcane farming predisposed participants to high malaria burden. Characterized relational interplay between these anthropogenic activities and P. falciparum parasitemia will be useful in developing tailored strategies towards optimized malaria control interventions in areas with and without anthropogenic activities.

Visceral leishmaniasis (VL) is a zoonotic disease in which dogs are the main reservoirs. Until now, the serological tests do not present satisfactory sensitivity for diagnosis of these hosts. One of the functions of extracellular vesicles (EVs) is related to immunological host response. Here, we evaluated the ability of EVs released by Leishmania (Leishmania) infantum promastigotes (Leish-EVs) to be source of antigens for use in serological diagnosis for human visceral leishmaniasis (HumVL) and canine visceral leishmaniasis (CanVL). A total of 300 sera were tested. The 155 human sera were divided into 4 groups and 145 canine sera into 3 groups. In human sera, Leish-EVs were reactive in 73/74 sera from patients with VL (Hum-VL) with 98.64% sensitivity. The 26 sera from healthy individuals (NH) and 27 from individuals with asymptomatic toxoplasmosis (ATx) were nonreagent (100% specificity). Leish-EVs-ELISA had cross-reactivity or inconclusive results in 13.5% of sera from Chagas disease patients (CD). In canine sera, Leish-EVs were reactive in 60/63 sera from dogs with CanVL (Can-VL) with 95.24% sensitivity. Leish-EVs were nonreactive in sera from 57 dogs without Can-VL (NC) and 25 with other infections (OIs) with 100% specificity. Hum-VL produced more IgG1 against Leish-EVs than IgG2, IgG3, and IgG4. Can-VL produced more IgG2 against Leish-EVs than IgG1. In conclusion, this study provides evidence that Leish-EVs released by L. (L.) infantum when used as antigen in ELISA identified the host antibodies. The methodology was effective for serological diagnosis of VL, since results exhibited good sensitivity and specificity for human and canine sera.

Fascioliosis is a food-borne zoonotic helminth infection caused by flatworms belonging to the family Fasciolidae, primarily affecting ruminants. The chronic form of fascioliosis is the most prevalent and is characterized by anemia, weight loss, cirrhosis, and liver dysfunction, along with atrophy, jaundice, and bottle jaw. In humans, infection results in fever, nausea, skin rashes, and severe abdominal pain. Climate changes and human-driven environmental alterations have contributed to an increasing incidence of fascioliosis in various regions. Fasciola species are widely distributed and have a high occurrence in tropical countries. Approximately 2.4-17 million humans are afflicted by fascioliosis in tropical and subtropical areas, with an additional 180 million facing the risk of infection. Fascioliosis poses a notable threat to ruminants; over 700 million production animals are at risk, and global annual financial losses surpass $3.2 billion. Conventional coprological methods and advanced molecular techniques are employed to diagnose fascioliosis in animals and humans. Within endemic areas, timely and accurate diagnosis is critical for successful prevention and treatment. Molecular approaches such as various PCR techniques and serological methods are extensively utilized to diagnose fascioliosis. In this review, we describe various conventional coprological and advanced DNA-based PCR techniques along with serological methods used for the screening, monitoring, and specific diagnosis of clinical and subclinical fascioliosis in humans and animals. The information accumulated in this review will be helpful for the diagnosis of fascioliosis in the field and research laboratories.

A better understanding of malaria epidemiology in both asymptomatic and symptomatic individuals is essential for developing strategies to control the disease. This study was conducted to determine Plasmodium infection prevalence and its associated factors among people living in Franceville (urban area) and in the villages of Pana and Mvengue (rural areas) in south-east Gabon between April and July 2022. This cross-sectional study was conducted among all consenting residents of Franceville, Mvengue, and Pana between April and July 2022. After obtaining informed consent, Plasmodium sp. infection was screened by microscopy, and a structured questionnaire was developed to record sociodemographic data, attitudes, and practices regarding malaria. A total of 976 participants were included, with 491 in urban areas and 485 in rural areas. The overall prevalence of Plasmodium sp. infection was 21.62% (211/976; 95% confidence interval (CI) [19.15-24.31]). The prevalence was highest in children aged 6-11 years. In urban areas, the prevalence was 19.35% (95/491; 95% CI [16.10-23.07]), and 96.84% of infections were asymptomatic. The most infected age group was 18-23 years. In rural areas, the prevalence was 23.92% (116/485, 95% CI [20.34-27.91], and 93.97% (109/116) of infections were asymptomatic. Socioeconomic characteristics, attitudes, and practices towards Plasmodium sp. infection were not associated with a risk of asymptomatic malaria infection. This study highlights the importance of asymptomatic Plasmodium sp. infection in south-east Gabon and the need for control strategies adapted to different areas and age groups. Detection and treatment of asymptomatic carriers could be an important lever for malaria control and elimination in the country.

Toxoplasma gondii (T. gondii) is an obligate, intracellular, neurotropic protozoan parasite. After primary infection, T. gondii parasite undergoes stage conversion from fast-replicating tachyzoites to slow-replicating dormant bradyzoites, particularly in the brain, and persists for a lifetime of an individual. In this study, the impact of T. gondii infection in individuals with psychological disorder, that is, major depressive disorder (MDD) has been studied. Ninety-five MDD (n = 95) patients were enrolled with age and sex-matched healthy controls (HCs, n = 90). The seroprevalence of T. gondii infection among these individuals was determined using the TOXO IgM/IgG Rapid Test Cassette that determines the anti-T. gondii IgM and IgG antibodies in the serum samples. Furthermore, to understand the impact of T. gondii in developing major depression, the serum level of neurotransmitters (i.e., dopamine, adrenaline, and noradrenaline) was determined using an enzyme-linked immunosorbent assay (ELISA). Our data suggest that anti-T. gondii IgG was slightly higher in MDD patients than in HCs. The level of dopamine was significantly lower in T. gondii-infected MDD patients than in HCs. However, adrenaline and noradrenaline levels showed increasing levels in T. gondii-infected MDD patients. The level of neurotransmitters was correlated with the DSM-D scores of MDD patients. These data, nevertheless, confirm that T. gondii might affect the level of neurotransmitters in MDD patients. However, whether the reduced level of dopamine and increased level of adrenaline and noradrenaline act as contributing factors for the development of MDD is yet to be known.