Parasitic Infections Research Articles

T. Muris Infection Dynamics of a Fresh, Wild Isolate: Is the Established E Isolate Still Relevant?

For decades, parasitic worms such as Trichuris muris have been maintained in laboratory animals, providing insights into host-parasite interactions and host immune responses. The most used T. muris isolate is the E isolate, established in the laboratory in 1954. However, one concern with these model systems is the potential for laboratory-induced selection and therefore changes in host-parasite interactions. To address these concerns, we compare the E isolate with a recently isolated T. muris isolate (M isolate), established from wild house mice (Mus musculus domesticus, Isle of May, UK), in their capacity to infect laboratory mice. High dose infection of C57BL/6 mice revealed that significantly more parasites of the M isolate survived to the adult stage compared to the E isolate. Worm persistence was associated with heightened TNF-α and IL-10 secretion upon parasite-specific re-stimulation, and higher serum IgG1 and IgG2c levels, concomitant with an increase in T-bet+ and ICOS+ CD4+ T effector-memory cells. Differences in host response to the isolates were not as pronounced during low dose infection. Our study highlights the need for regular evaluation of lab-maintained parasite isolates against freshly isolated parasites to understand whether the established lab strains remain relevant model systems for our understanding of parasitic infections.

Host-Parasite Interaction Between the Nematoda Procamallanus (Spirocamallanus) paraensis and Fish Hoplias malabaricus From the Natural Environment in the Brazilian Amazon.

Histopathological studies of parasitic infections in fish from the natural environment of Brazilian Amazon, are quite scarce. In this study, we investigated the histopathological changes of the proximal intestine of specimens of the Amazonian fish Hoplias malabaricus infected by the hematophagous nematode Procamallanus (Spirocamallanus) paraensis. The prevalence of the infection was 60%, with an average abundance of 1.46 and an average intensity of 2.43 parasites/fish. No significant difference was observed in the prevalence of infection and fish size or sex, but larger fish showed greater infection intensity, which was also significantly higher in male hosts. Histological sections of the proximal intestine showed reduction and loss of the epithelial lining, exposure of the lamina propria where the nematode interacts with the intestine wall, through the insertion of the buccal capsule and fish cellular debris in the intestinal lumen. In addition, areas with bleeding and inflammatory infiltrate were observed, but no changes or presence of parasite structures were observed in the other tunics of the intestinal wall.

Schistosome and malaria exposure and urban–rural differences in vaccine responses in Uganda: a causal mediation analysis using data from three linked randomised controlled trials

Vaccine immunogenicity and effectiveness vary geographically. Chronic immunomodulating parasitic infections including schistosomes and malaria have been hypothesised to be mediators of geographical variations. We compared vaccine-specific immune responses between three Ugandan settings (schistosome-endemic rural, malaria-endemic rural, and urban) and did causal mediation analysis to assess the role of Schistosoma mansoni and malaria exposure in observed differences. We used data from the control groups of three linked randomised trials investigating the effects of intensive parasite treatment among schoolchildren. All participants received the BCG vaccine (week 0); yellow fever (YF-17D), oral typhoid (Ty21a), human papillomavirus (HPV; week 4); and HPV booster and tetanus-diphtheria (week 28). Primary outcomes were vaccine responses at week 8 and, for tetanus-diphtheria, week 52. We estimated the total effect (TE) of setting on vaccine responses and natural indirect effect (NIE) mediated through current or previous infection with S mansoni or malaria, and baseline vaccine-specific responses. We included 239 (43%) participants from the schistosomiasis-endemic setting, 171 (30%) from the malaria-endemic setting, and 151 (27%) from the urban setting. At week 8, vaccine responses were lower in rural settings: schistosomiasis-endemic versus urban settings (TE geometric mean ratio for YF-17D plaque reduction neutralisation at 50% (PRNT50) titres 0·58 [95% CI 0·37 to 0·91], for S Typhi O-lipopolysaccharide-specific IgG 0·61 [0·40 to 0·93], and for tetanus-specific IgG 0·33 [0·22 to 0·51]); malaria-endemic versus urban settings (YF-17D 0·70 [0·49 to 0·99], S Typhi O-lipopolysaccharide-specific IgG 0·29 [0·20 to 0·43], and tetanus-specific IgG 0·53 [-0·35 to 0·80]). However, we found higher BCG-specific IFNγ responses in the malaria-endemic versus urban setting (1·54 [1·20 to 1·98]). The estimated NIEs of setting on vaccine responses mediated through previous and current S mansoni and malaria were not statistically significant. For malaria-endemic versus urban settings, baseline vaccine-specific responses contributed to some but not all differences: S Typhi O-lipopolysaccharide-specific IgG at week 8 (57.9% mediated [38·6 to 77·2]) and week 52 (70·0% mediated [49·4 to 90·6]) and BCG at week 52 (46.4% mediated [-4·8 to 97·7]). We found significant variation in vaccine response between urban and rural settings but could not confirm a causal role for schistosome or malaria exposure. Other exposures require consideration. UK Medical Research Council.

Penetration Enhancer-Free Mixed Micelles for Improving Eprinomectin Transdermal c Efficiency in Animal Parasitic Infections Therapy

Penetration Enhancer-Free Mixed Micelles for Improving Eprinomectin Transdermal c Efficiency in Animal Parasitic Infections Therapy

Cytotoxic effects of ivermectin on Giardia lamblia: induction of apoptosis and cell cycle arrest

IntroductionGiardia lamblia is a flagellated protozoan parasite causing giardiasis, a common intestinal infection characterized by diarrhea, abdominal cramps, and nausea. Treatments employed to combat this parasitic infection have remained unchanged for the past 40 years, leading to the emergence of resistant strains and prompting the search for new therapeutic agents.MethodsThis study investigated the cytotoxic effects of ivermectin (IVM) on G. lamblia trophozoites. We conducted dose-response experiments to assess IVM-induced cytotoxicity. We utilized various biochemical and ultrastructural analyses to explore the underlying mechanisms of cell death, including reactive oxygen species (ROS) production, DNA fragmentation, cell cycle arrest, and apoptosis markers.ResultsOur findings demonstrate that IVM induces dose-dependent cytotoxicity and triggers cell death pathways. We found that IVM treatment generates elevated levels of reactive oxygen species (ROS), DNA fragmentation, and arrests of trophozoites in the cell cycle’s S phase. Additionally, ultrastructural analysis reveals morphological alterations consistent with apoptosis, such as cytoplasmic vacuolization, chromatin condensation, and tubulin distribution.DiscussionThe insights gained from this study may contribute to developing new therapeutic strategies against giardiasis, addressing the challenge posed by drug-resistant strains.

Toxoplasmosis infection in an HIV-negative patient presenting with clinical and MRI findings similar to those of multiple sclerosis

Toxoplasmosis is a parasitic infection that can present in various clinical forms, ranging from asymptomatic to severe neurological manifestations. The primary sources of infection include undercooked meat, unwashed produce and contact with cat faeces. Toxoplasmosis can lead to encephalitis, particularly in immunocompromised patients, and is often misdiagnosed as other neurological conditions such as multiple sclerosis (MS). We report the case of a 44-year-old male from Almaty, Kazakhstan, who presented with neurological symptoms including headaches, dizziness, diplopia, leg weakness and elevated blood pressure. The patient had a history of consuming undercooked meat, but no prior neurological conditions. Initial magnetic resonance imaging (MRI) revealed demyelinating lesions, leading to a diagnosis of MS. However, high levels of IgG antibodies against Toxoplasma gondii were detected, prompting further testing. A polymerase chain reaction test for toxoplasmosis was negative, but the patient was treated empirically with trimethoprim and sulfamethoxazole for six months. A follow-up MRI showed a significant reduction in brain lesions, and the patient’s symptoms improved.

Gastrointestinal parasites in free grazing goats from Ayacucho, Peru: prevalence and risk factors associated with infection in herds

This study assessed the prevalence and risk factors associated with gastrointestinal parasite infection in goats in Ayacucho, Peru. Fecal samples were collected from a total of 254 goats from four districts of Ayacucho: Ocaña (89), Colca (76), Pacaicasa (64), and Luricocha (25) during the dry season; recording the location, sex, and age of the animals. The fecal samples were analyzed using the flotation technique in salt and sugar solution, and modified McMaster egg counting techniques for eggs/oocysts (epg/opg) of gastrointestinal parasites. The associations between location, sex, and age with the prevalence of gastrointestinal parasites were analyzed using the chi-square test. Fecal samples showed an overall parasite prevalence of 87.80%. The identified parasites were Eimeria spp. (86.22%), Strongyle type eggs (STE) (65.75%), Skrjabinema spp. (7.87%), Trichuris spp. (3.15%) and Moniezia spp. (3.15%). There was a significant association between the location and the presence of parasites (p < 0.05); where STE was more prevalent in the district of Colca (98.68%); Trichuris spp. in Pacaycasa (9.38%); Skrjabinema spp. (48.00%), Moniezia spp. (12.00%) and Eimeria spp. (100%) were more prevalent in Luricocha. Sex had a significant association with the prevalence of Eimeria spp., Skrjabinema spp. and Moniezia spp. (p < 0.05); while age had a significant association with parasitosis only for Trichuris spp. and Moniezia spp. (p < 0.05). The epg/opg values revealed a higher parasite burden in goats from Colca compared to the other locations (p < 0.05). There was also no statistical relationship between fecal egg/oocyst counts and sex or age, nevertheless, there were moderate and high parasitic burdens. The high prevalence of parasites such as nematodes, cestodes, and coccidia suggests the need to implement strategic control and prevention programs in free-grazing goats. Location and sex were the most relevant risk factors for parasitosis in Ayacucho, Peru.

Morphological and molecular identification of Eimeria rajasthani (coccidia: Eimeriidae) in the dromedary camel (Camelus dromedarius) in Riyadh, Saudi Arabia

IntroductionCoccidiosis is a serious parasitic disease in camels caused by an intestinal protozoan parasite of the genus Eimeria, which is linked to significant causes of reduced milk and meat production. In Saudi Arabia, scare literature focused on the coprological investigation of dromedary camels (Camelus dromedarius). To determine the taxonomic status of camel parasite species, we performed morphological characterization of oocysts and genetic analysis (18S rRNA and ITS-1 gene regions) of Eimeria species collected from camels in Riyadh, Saudi Arabia.MethodsA total of 150 faecal samples were obtained from camels at the old camel market. These samples were tested for the presence of Eimeria oocysts using the conventional floatation technique before being sporulated in a 2.5% potassium dichromate solution. Eimeria oocysts were morphologically and molecularly examined and identified, and the infection rate of parasitic infections was determined.ResultsOur findings revealed that the overall frequency of oocysts was 30%. The identified species was Eimeria rajasthani, which had a typical ellipsoidal oocyst shape. Oocystic polar granule, micropyle, micropylar cap, and oocyst residuum are not visible. Sporocysts are oval with stieda body. Sporocyst residuum contains many granules and sporozoites with refractile bodies and nuclei. Genetic analyses of the sequence data from the partial 18S rRNA and ITS-1 gene regions revealed that the sequences obtained from E. rajasthani oocysts are related to DNA sequences reported from E. lamae from the Alpaca from China, particularly the 18S rRNA sequences.ConclusionThis study emphasized the need to use molecular phylogenetic tools to describe camel intestinal coccidian parasites with traditional morphology-based approaches to better understand their biology. For camel husbandry and disease control, more studies should be conducted to better understand the epidemiology of these protozoan parasites.

Health Catch-UP!: a realist evaluation of an innovative multi-disease screening and vaccination tool in UK primary care for at-risk migrant patients

BackgroundMigrants to the UK face disproportionate risk of infections, non-communicable diseases, and under-immunisation compounded by healthcare access barriers. Current UK migrant screening strategies are unstandardised with poor implementation and low uptake. Health Catch-UP! is a collaboratively produced digital clinical decision support system that applies current guidelines (UKHSA and NICE) to provide primary care professionals with individualised multi-disease screening (7 infectious diseases/blood-borne viruses, 3 chronic parasitic infections, 3 non-communicable disease or risk factors) and catch-up vaccination prompts for migrant patients.MethodsWe carried out a mixed-methods process evaluation of Health Catch-UP! in two urban primary healthcare practices to integrate Health Catch-UP! into the electronic health record system of primary care, using the Medical Research Council framework for complex intervention evaluation. We collected quantitative data (demographics, patients screened, disease detection and catch-up vaccination rates) and qualitative participant interviews to explore acceptability and feasibility.ResultsNinety-nine migrants were assessed by Health Catch-UP! across two sites (S1, S2). 96.0% (n = 97) had complete demographics coding with Asia 31.3% (n = 31) and Africa 25.2% (n = 25), the most common continents of birth (S1 n = 92 [48.9% female (n = 44); mean age 60.6 years (SD 14.26)]; and S2 n = 7 [85.7% male (n = 6); mean age 39.4 years (SD16.97)]. 61.6% (n = 61) of participants were eligible for screening for at least one condition and uptake of screening was high 86.9% (n = 53). Twelve new conditions were identified (12.1% of study population) including hepatitis C (n = 1), hypercholesteraemia (n = 6), pre-diabetes (n = 4), and diabetes (n = 1). Health Catch-UP! identified that 100% (n = 99) of patients had no immunisations recorded; however, subsequent catch-up vaccination uptake was poor (2.0%, n = 1). Qualitative data supported acceptability and feasibility of Health Catch-UP! from staff and patient perspectives, and recommended Health Catch-UP! integration into routine care (e.g. NHS health checks) with an implementation package including staff and patient support materials, standardised care pathways (screening and catch-up vaccination, laboratory, and management), and financial incentivisation.ConclusionsClinical Decision Support Systems like Health Catch-UP! can improve disease detection and implementation of screening guidance for migrant patients but require robust testing, resourcing, and an effective implementation package to support both patients and staff.

From host individual traits to community structure and composition: Bartonella infection insights

BackgroundPhylogeny, combined with trait-based measures, offers insights into parasite sharing among hosts. However, the specific traits that mediate transmission and the aspects of host community diversity that most effectively explain parasite infection rates remain unclear, even for the Bartonella genus, a vector-borne bacteria that causes persistent blood infections in vertebrates.MethodsThis study investigated the association between rodent host traits and Bartonella infection, as well as how rodent community diversity affects the odds of infection in the Atlantic Forest, using generalized linear models. Additionally, we assessed how host traits and phylogenetic similarities influence Bartonella infection among mammal species in Brazil. To this end, rodents were sampled from ten municipalities in Rio de Janeiro, southeastern Brazil. Then, we calculated several diversity indices for each community, including Rényi’s diversity profiles, Fisher’s alpha, Rao’s quadratic entropy (RaoQ), Functional Diversity (FDis), Functional Richness (FRic), and Functional Evenness (FEve). Finally, we compiled a network encompassing all known interactions between mammal species and Bartonella lineages recorded in Brazil.ResultsWe found no significant relationship between diversity indices and the odds of Bartonella infection in rodent communities. Furthermore, there was no statistical support for the influence of individual-level traits (e.g., body length, sex, and age) or species-level ecological traits (e.g., locomotor habitat, dietary guild, and activity period) on Bartonella infection in rodents. A country-scale analysis, considering all mammal species, revealed no effect of host traits or phylogeny on Bartonella infection.ConclusionsThis study highlighted wild mammals that share Bartonella lineages with livestock, synanthropic, and domestic animals, underscoring the complexity of their maintenance cycle within the One Health framework. A key question arising from our findings is whether molecular host–cell interactions outweigh host body mass and ecological traits in influencing Bartonella infection, potentially opening new avenues for understanding host–parasite relationships and infection ecology.Graphical

Racemose neurocysticercosis of the basal arachnoid cisterns: illustrative case.

Neurocysticercosis is a parasitic infection of the central nervous system caused by the helminth Taenia solium. Racemose neurocysticercosis is a rare form of the disease that specifically involves cerebrospinal fluid-filled spaces in the brain and carries a high rate of complications and mortality. This report describes the case of a 37-year-old man who developed headaches and nausea, which were found to be secondary to racemose neurocysticercosis. He ultimately required an endoscopic third ventriculostomy, which provided transient symptom relief. In the weeks following the procedure, his symptoms returned, at which point a recommendation to proceed with a ventriculoperitoneal shunt was made. The presentation of racemose neurocysticercosis is wide-ranging and often nonspecific. Patients who respond well to initial surgical management with endoscopic third ventriculostomy can still require more durable measures, such as a ventriculoperitoneal shunt, in the following months. https://thejns.org/doi/10.3171/CASE24489.

Species of Monogenean Parasites Infesting Cyprinus carpio and Planiliza abu in Lake Balloran Dam-Syria

This study was conducted in Lake Balloran Dam and involved 68 fish specimens, including 23 common carp (Cyprinus carpio) and 45 Abu mullet (Liza abu). Sampling was carried out monthly and randomly from July 2020 to August 2021. The research addressed parasitic infections in these two important species of freshwater fish. This work identifies five parasitic species of monogeneans, three of them were isolated from common carp and identified as species belonging to the genus Dactylogyrus: D. dogieli, D. minutus, and D. extensus. One species was isolated from both the common carp and Abu mullet, and identified as the species Gyrodactylus derjavini, and the other species, G. elegans, was isolated from only the common carp. Dactylogyrus species were primarily isolated from the gills of the studied fish, whereas Gyrodactylus species were found on the skin and fins. This study is of fundamental interest for the knowledge of parasitic biodiversity on the Asian continent that are widespread in vast bodies of water, and the species D. dogieli and G. derjavini were recorded for the first time in Syrian freshwater in this study.

The Pharmacokinetics of Subcutaneous Eprinomectin in Plasma and Milk in Dry Dairy Cattle.

Parasitic infections in dairy cattle reduce herd immunity, milk production, and conception rates. This leads to higher production costs, compromised animal welfare, and increased interest in extralabel drug use. The extralabel use of anthelmintics poses food safety risks for consumers since appropriate withdrawal intervals in milk have yet to be established. Although topical eprinomectin has no milk withdrawal time, more research is needed to determine the residues present in milk after subcutaneous administration. This study aimed to characterize the pharmacokinetics of injectable eprinomectin in dry dairy cows. We hypothesized that, when given at the labeled dose, eprinomectin residues in dry dairy cattle would be below the FDA milk tolerance at the onset of lactation. Plasma was collected daily from 13 mature dairy cattle for 7 days postadministration, followed by periodic samples for 90 days. After calving, milk was collected daily until 90 days. Eprinomectin concentrations were measured using HPLC-fluorescence detection. The maximum eprinomectin concentration in plasma and milk was approximately 36 ng/mL 43 h after administration and 3 ng/mL at the onset of lactation, respectively. The low eprinomectin levels in milk collected from these lactating dairy cattle suggest that administering eprinomectin at dry-off is unlikely to result in violative residues. However, subcutaneous eprinomectin in lactating dairy cattle would be hard to justify unless there is evidence that the approved topical formulation is clinically ineffective.

A Rare Presentation of Breast Filariasis: A Case Report

Background: Filariasis is a common tropical disease but filariasis in breast is uncommon. Mostly, presentation is with typical symptoms of inflammation and lump. Atypical presentation is very rare and needs to be reported. Case Presentation: We report a case of breast filariasis with its atypical presentation and challenges faced for diagnosis. Patient was successfully treated with DEC (Di-ethyl-carbamazine). Conclusion: A high index of suspicion is required for its diagnosis in endemic zones even with atypical presentation, only then can correct treatment for the disease be given and prevention in progression and spread of disease achieved. This case report urges clinicians to keep a fair degree of clinical suspicion for parasitic infections as a cause of breast lump, especially in endemic countries and when presentation is atypical.

Elevated circulating group-2 innate lymphoid cells expressing activation markers and correlated tryptase AB1 levels in active ascariasis

IntroductionAscaris lumbricoides infection is one of the most common soil-transmitted helminthiasis and IgE response to this helminth may increase the risk of asthma, bronchial hyperreactivity and atopy. There is not enough evidence showing the role of group-2 innate lymphoid cells (ILC2) in the pathogenesis of helminth infections in humans. Here, we aimed to investigate and characterize the influence of Ascaris lumbricoides infection on circulating ILCs in endemically exposed subjects.MethodsNon-infected (NI; n=16) and Ascaris-infected (AI; n=16) subjects from an endemic area were included. Two consecutive stool samples from each subject were examined by Kato-Katz to define parasite infection. Antibodies to the ABA-1 antigen of Ascaris and Ascaris extract were measured by ELISA. ILC subsets and their activation markers (CD25, CD69, thymic stromal lymphopoietin receptor (TSLPR) were evaluated in its PBMC by flow cytometry. Proximity extension assay (PEA) was performed to explore plasma proteins associated to infection.ResultsNo significant differences in the relative or absolute frequencies of total ILCs, ILC1, ILC2 and ILC3 cells were observed regarding the infection status. However, within AI group, IgE-sensitized subjects to ABA-1 had higher frequencies and counts of ILC2 (p&amp;lt;0.05). Frequencies of CD25+, CD69+ and TSLPR+ ILC2 were higher in AI compared to the NI (p&amp;lt;0.01). Additionally, egg burden was positively correlated with CD69+ ILC2 frequencies (r=0.67; p=0.005). Tryptase alpha/beta 1 (TPSAB1), GP6 and several plasma proteins associated with cell growth and granulocyte chemotaxis were highly expressed in the AI group (p&amp;lt;0.05). Interestingly, TPSAB1 levels were positively correlated with ILC2 expressing activation markers frequencies, egg burden and IgE levels against Ascaris.DiscussionAscaris infection is associated with increased expression of ILC2 activation markers and TPSAB1, which may contribute to the type-2 response.

Intestinal Parasites and Hematological Parameters in Children Living in Ambatoboeny District, Madagascar

Madagascar is one of the poorest countries in the world. The country’s extreme weather conditions, poor sanitation, and weak economy facilitate the spread of parasitic diseases. Infections with intestinal parasites are particularly dangerous for children because they can cause malnutrition and anemia, which, in turn, have a negative effect on children’s cognitive functions and physical development. The aim of the present study was to analyze the prevalence of intestinal parasites and to assess hematological parameters in a group of children living in northern Madagascar. The screening was conducted in May 2024 in the Clinique Medicale Beyzym in Manerinerina, the Ambatoboeny district. It involved a sample of 208 children aged 0–17 years. Single stool samples were collected from all study participants. The samples were fixed in SAF fixative and then transported from Africa to Europe for further diagnostics at the Department of Epidemiology and Tropical Medicine, the Military Institute of Medicine–the National Research Institute in Poland. First, the samples were analyzed by light microscopy methods using three different diagnostic techniques (direct smear, decantation with distilled water, and the Fülleborn method). Next, they were tested by molecular biology methods (real-time PCR). Blood samples for the assessment of hematological parameters were collected at the healthcare center in Madagascar. The prevalence of intestinal parasites in the study sample was 61.5%. Helminths were found in 15.2% of the investigated children, and Giardia intestinalis (20.5%) was found to be the most prevalent parasite in the study population. Most infections were caused by potentially pathogenic stramenopila Blastocystis spp. (32.0%). Mean Hb, HCT, MCV, MCH, and MCHC levels in the study participants were below normal values. However, no correlation was found between the presence of a parasitic infection and low hematological parameters, which are a clinical sign of anemia. High rates of infections with intestinal parasites in children living in northern Madagascar support the necessity to introduce long-term preventive measures, which would limit the spread of parasitic diseases in the Malagasy population. Low hematological parameters in non-infected children may be indicative of persistent malnutrition or infection with other parasites, e.g., malaria or schistosomiasis.

An Expression Quantitative Trait Locus of Fc Gamma Receptor Genes is Associated with Anti-Malarial IgG Responses and Infection Levels in Burkinabe Families.

The interaction between antibodies and Fc gamma receptors (FcγRs) plays a critical role in regulating immune responses to Plasmodium falciparum. Polymorphisms in genes encoding FcγRs influence the host's capacity to control parasite infection. This study investigates whether non-coding variants influencing FcγR expression are associated with anti-malarial immunization and infection traits. We utilized eQTL databases and functional annotations to identify non-coding variants, specifically rs1771575, rs2099684, and rs6700241, within the FCGR gene cluster. In addition, we examined the coding variants rs1801274 (p.His167Arg) and rs1050501 (p.Ile231Thr), which affect the affinity of FcγRIIa and FcγRIIb for IgG. These variants were genotyped in 163 individuals from Burkinabe families. Family-based linear mixed regression and Quantitative Transmission Disequilibrium Tests (QTDT) analyses were performed to assess associations with IgG levels and malaria infection, accounting for relevant covariates. Linear mixed models identified rs1771575 as associated with total IgG levels, while both rs1771575 and rs1801274 were linked to IgG2, and rs1050501 to IgG1 levels. A haplotype combining rs2099684 and rs6700241 was positively associated with IgG1. The rs1771575-CC and rs1050501-TT genotypes correlated with higher infection levels in children. QTDT models confirmed the association of rs1771575 with IgG2 and infection in children. Our findings suggest that the intergenic variant rs1771575 serves as an independent marker for IgG levels and blood infection in children. This highlights the interplay between regulatory variants and coding mutations in FCGR, which may influence immune function and antibody production. These results underscore the potential for personalized strategies to monitor humoral responses in malaria-endemic regions.

Molecular survey of certain protozoan agents that cause diarrhea in children in Sudan

Introduction Diarrhea is a significant health problem in the Third World. Identification of the pathogen that causes diarrhea is vital for measures to prevent and control this disease. There are also very few reports of diarrhea in Sudan. Our study aimed to determine the Prevalence of specific protozoan pathogens (Entamoeba histolytica, Cryptosporidium parvum., and Giardia spp) in children in Khartoum, Sudan. Methods We conducted a cross-sectional survey among children under five years of age hospitalized with acute diarrhea between April and December 2014. Diarrheal stool samples were collected, and E. histolytica, C. parvum, and Giardia spp were examined using multiplex real-time PCR. Results Four hundred and thirty-seven children with acute diarrhea were included in this study; the higher prevalence of diarrhea was in the age ≤ 2 years old (403, 92.2%), &gt;2–≤4 years (32, 7.3%), and &gt;4–&lt;5 years (2, 0.5%). The male-to-female ratio in this study was 1:1.7. Infection with intestinal parasite was found in 155 (35.5%) cases, and co-infection was detected in 16 (3.7%) cases. Giardia spp (18.8%) and C. parvum (15.8%) were the most frequently identified parasites, followed by E. histolytica (0.9). The parasite infection rate was highest and lowest in the under 2-year-old group 143 (35.5%) and the 2–4-year-old group 12 (37.5%). The infection rate was higher in boys 104 (37.7%) than in girls 51 (31.7%). The number of positive cases was higher in the rainy season (August to December) 143 (37.4%), corresponding with that in the dry Season (April to June) 12 (21.8%). Discussion Our present study demonstrated the high prevalence of Giardia spp and C. parvum in children with diarrhea in the Khartoum region and the usefulness of the multiplex real-time method in disclosing pathogenic protozoal agents. Our result highlighted the necessity of developing intervention measurement and control strategies to deal with childhood parasitic diarrhea in this region.

Optimization of 18 S rRNA metabarcoding for the simultaneous diagnosis of intestinal parasites

Recent advancements in next-generation sequencing (NGS) technologies have created new opportunities for comprehensive screening of multiple parasite species. In this study, we cloned the 18 S rDNA V9 region of 11 species of intestinal parasites into plasmids. Equal amounts and concentrations of these 11 plasmids were pooled, and amplicon NGS targeting the 18 S rDNA V9 region was performed using the Illumina iSeq 100 platform. A total of 434,849 reads were identified, and all 11 parasite species were detected, although the number of output reads for each parasite varied. The read count ratio, in descending order, was as follows: Clonorchis sinensis, 17.2%; Entamoeba histolytica, 16.7%; Dibothriocephalus latus, 14.4%; Trichuris trichiura, 10.8%; Fasciola hepatica, 8.7%; Necator americanus, 8.5%; Paragonimus westermani, 8.5%; Taenia saginata, 7.1%; Giardia intestinalis, 5.0%; Ascaris lumbricoides, 1.7%; and Enterobius vermicularis, 0.9%. We found that the DNA secondary structures showed a negative association with the number of output reads. Additionally, variations in the amplicon PCR annealing temperature affected the relative abundance of output reads for each parasite. These findings can be applied to improve parasite detection methodologies and ultimately enhance efforts to control and prevent intestinal parasitic infections.

Type 1 diabetes and parasite infection: An exploratory study in NOD mice.

Microorganisms have long been suspected to influence the outcome of immune-related syndromes, particularly autoimmune diseases. Type 1 diabetes (T1D) results from the autoimmune destruction of the insulin-producing beta cells of pancreatic islets, causing high glycemia levels. Genetics is part of its aetiology, but environmental factors, particularly infectious microorganisms, also play a role. Bacteria, viruses, and parasites influence the outcome of T1D in mice and humans. We used nonobese diabetic (NOD) mice, which spontaneously develop T1D, to investigate the influence of a parasitic infection, leishmaniasis. Leishmania amazonensis is an intracellular eukaryotic parasite that replicates predominantly in macrophages and is responsible for cutaneous leishmaniasis. The implication of Th1 immune responses in T1D and leishmaniasis led us to study this parasite in the NOD mouse model. We previously constructed osteopontin knockout mice with a NOD genetic background and demonstrated that this protein plays a role in the T1D phenotype. In addition, osteopontin (OPN) has been found to play a role in the immune response to various infectious microorganisms and to be implicated in other autoimmune conditions, such as multiple sclerosis in humans and experimental autoimmune encephalomyelitis (EAE) in mice. We present herein data demonstrating the role of OPN in the response to Leishmania in NOD mice and the influence of this parasitic infection on T1D. This exploratory study aimed to investigate the environmental infectious component of the autoimmune response, including Th1 immunity, which is common to both T1D and leishmaniasis.