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The American Journal of Tropical... Aug 2020We reported 865 cases of soil-transmitted nematodiasis occurring in Japan during 2000-2017. The predominant nematode was ( = 279, 32.3% of all cases), and other species...
We reported 865 cases of soil-transmitted nematodiasis occurring in Japan during 2000-2017. The predominant nematode was ( = 279, 32.3% of all cases), and other species included (30.7%), (23.1%), and spp. (13.9%). was detected primarily in patients in Okinawa and Kagoshima prefectures, which are in the south of Japan and are endemic areas for this parasitic infection, and also in about half of the prefectures of all Japan. At least 15.5 cases of strongyloidiasis occurred on average each year. The period incidence rate of strongyloidiasis cases relative to the total population of Japan was 0.012 cases per 10 person-years. The male-to-female ratio was 2.1. The average age was 75.1 ± 16.9 years, and 96.1% of patients were older than 50 years. Several reasons may explain why this previously non-endemic outside of Okinawa region, serious nematode disease is now found in much of Japan, including the increased number of transmigration and sightseeing trips in Japan, use of immunosuppressive drugs, and lack of awareness of the risks. Thus, information of strongyloidiasis and its risks must be disseminated to travelers, residents, and physicians to prevent this life-threatening parasite infection.
Topics: Adult; Aged; Aged, 80 and over; Ancylostomiasis; Animals; Ascariasis; Ascaris lumbricoides; Female; Humans; Japan; Male; Middle Aged; Strongyloides stercoralis; Strongyloidiasis; Trichuriasis; Trichuris; Young Adult
PubMed: 32588800
DOI: 10.4269/ajtmh.19-0969 -
Parasite Immunology Apr 2022This study investigated whether prior exposure to helminths (Ascaris IgE, Ascaris eggs and Trichuris eggs) either in childhood or in adulthood, and residence in rural...
This study investigated whether prior exposure to helminths (Ascaris IgE, Ascaris eggs and Trichuris eggs) either in childhood or in adulthood, and residence in rural and resource-limited urban areas influence allergy outcomes (asthma, rhinitis, IgE atopy and food allergy) in a South African population. Participants historical and present allergies data were collected through questionnaires and clinical record files. Coproscopy and immunoassays (ImmunoCAP Phadiatop, total IgE and allergen-specific fx3 IgE immunoassays and Ascaris IgE radioallergosorbent [RAST] tests) were used for active helminthiasis and allergy screens respectively. Data were analysed using logistic regression analysis, and models were adjusted for age, gender and locality. High Ascaris IgE was significantly associated with asthma (adjusted odds ratio [aOR] = 2.20, p = .047), IgE atopy (aOR = 18.18, p < .0001) and food allergy (aOR = 14.47, p < .0001). Asthma was significantly less likely among participants with Ascaris eggs (aOR = 0.43, p = .048) and Trichuris eggs (aOR = 0.36, p = .024). The findings of co-occurrent helminthiasis and allergic disorders in a population that has resided both in rural and peri-urban informal settlements both oppose and agree with two main notions of the hygiene hypothesis that (i) individuals residing in rural settings with poor sanitation and geohelminth infection are less prone to allergy, and (ii) helminth infections protect against allergy respectively. Further research is warranted.
Topics: Adult; Animals; Ascaris; Asthma; Helminthiasis; Humans; Hypersensitivity; Hypersensitivity, Immediate; Immunoglobulin E; Skin Tests; South Africa; Trichuris
PubMed: 35188279
DOI: 10.1111/pim.12913 -
Parasitology Feb 2021Ascaris lumbricoides and Ascaris suum are helminth parasites of humans and pigs, respectively. The life cycle of Ascaris sets it apart from the other soil-transmitted...
Ascaris lumbricoides and Ascaris suum are helminth parasites of humans and pigs, respectively. The life cycle of Ascaris sets it apart from the other soil-transmitted helminths because of its hepato-tracheal migration. Larval migration contributes to underestimated morbidity in humans and pigs. This migration, coupled with a lack of a murine model in which the Ascaris parasite might complete its life cycle, has undoubtedly contributed to the neglected status of the ascarid. Our knowledge of the epidemiology of adult worm infections had led us to an enhanced understanding of patterns of infection such as aggregation and predisposition; however, the mechanisms underlying these complex phenomena remain elusive. Carefully controlled experiments in defined inbred strains of mice – with enhanced recovery of larvae in tandem with measurements of cellular, histopathological and molecular processes – have greatly enhanced our knowledge of the early phase of infection, a phase crucial to the success or failure of adult worm establishment. Furthermore, the recent development of a mouse model of susceptibility and resistance, with highly consistent and diverging Ascaris larval burdens in the murine lungs, represents the extremes of the host phenotype displayed in the aggregated distribution of worms and provides an opportunity to explore the mechanistic basis that confers predisposition to light and heavy Ascaris infection. Certainly, detailed knowledge of the cellular hepatic and pulmonary responses at the molecular level can be accrued from murine models of infection and, once available, may enhance our ability to develop immunomodulatory therapies to elicit resistance to infection.
PubMed: 33612124
DOI: 10.1017/S0031182021000366 -
PLoS Neglected Tropical Diseases Apr 2022Intestinal helminth parasites (worms) have afflicted humans throughout history and their eggs are readily detected in archaeological deposits including at locations...
Intestinal helminth parasites (worms) have afflicted humans throughout history and their eggs are readily detected in archaeological deposits including at locations where intestinal parasites are no longer considered endemic (e.g. the UK). Parasites provide valuable archaeological insights into historical health, sanitation, hygiene, dietary and culinary practices, as well as other factors. Differences in the prevalence of helminths over time may help us understand factors that affected the rate of infection of these parasites in past populations. While communal deposits often contain relatively high numbers of parasite eggs, these cannot be used to calculate prevalence rates, which are a key epidemiological measure of infection. The prevalence of intestinal helminths was investigated through time in England, based on analysis of 464 human burials from 17 sites, dating from the Prehistoric to Industrial periods. Eggs from two faecal-oral transmitted nematodes (Ascaris sp. and Trichuris sp.) and the food-derived cestodes (Taenia spp. and Diphyllobothrium latum syn Dibothriocephalus latus) were identified, although only Ascaris was detected at a high frequency. The changing prevalence of nematode infections can be attributed to changes in effective sanitation or other factors that affect these faecal-oral transmitted parasites and the presence of cestode infections reflect dietary and culinary preferences. These results indicate that the impact of helminth infections on past populations varied over time, and that some locations witnessed a dramatic reduction in parasite prevalence during the industrial era (18th-19th century), whereas other locations continued to experience high prevalence levels. The factors underlying these reductions and the variation in prevalence provide a key historical context for modern anthelmintic programs.
Topics: Animals; Ascaris; Diphyllobothrium; Feces; Helminthiasis; Helminths; Intestinal Diseases, Parasitic; Prevalence; United Kingdom
PubMed: 35446843
DOI: 10.1371/journal.pntd.0010312 -
Parasitology Apr 2021The soil-transmitted helminth Ascaris lumbricoides infects ~800 million people worldwide. Some people are heavily infected, harbouring many worms, whereas others are...
The soil-transmitted helminth Ascaris lumbricoides infects ~800 million people worldwide. Some people are heavily infected, harbouring many worms, whereas others are only lightly infected. The mechanisms behind this difference are unknown. We used a mouse model of hepatic resistance to Ascaris, with C57BL/6J mice as a model for heavy infection and CBA/Ca mice as a model for light infection. The mice were infected with the porcine ascarid, Ascaris suum or the human ascarid, A. lumbricoides and immune cells in their livers and spleens were enumerated using flow cytometry. Compared to uninfected C57BL/6J mice, uninfected CBA/Ca mice had higher splenic CD4+ and γδ T cell counts and lower hepatic eosinophil, Kupffer cell and B cell counts. Infection with A. suum led to expansions of eosinophils, Kupffer cells, monocytes and dendritic cells in the livers of both mouse strains and depletions of hepatic natural killer (NK) cells in CBA/Ca mice only. Infection with A. lumbricoides led to expansions of hepatic eosinophils, monocytes and dendritic cells and depletions of CD8+, αβ, NK and NK T cells in CBA/Ca mice, but not in C57BL/6J mice where only monocytes expanded. Thus, susceptibility and resistance to Ascaris infection are governed, in part, by the hepatic immune system.
Topics: Animals; Ascariasis; Ascaris lumbricoides; Ascaris suum; Disease Resistance; Disease Susceptibility; Flow Cytometry; Immunity, Innate; Liver; Male; Mice; Mice, Inbred C57BL; Spleen
PubMed: 33431071
DOI: 10.1017/S0031182021000020 -
Frontiers in Immunology 2023The COVID-19 pandemic has had devastating effects worldwide, but the trajectory of the pandemic has been milder in Low-and-Middle-Income Countries (LMICs), including...
INTRODUCTION
The COVID-19 pandemic has had devastating effects worldwide, but the trajectory of the pandemic has been milder in Low-and-Middle-Income Countries (LMICs), including those in Africa. Co-infection with helminths, such as Ascaris lumbricoides, has been suggested as a possible factor contributing to the reduced severity observed in these regions.
METHODS
The present study investigated the association between Ascaris-specific antibody levels and COVID-19 severity in 276 SARS-CoV-2-infected individuals in Benin. Participants were categorized into asymptomatic (n=100), mild (n=150), and severe (n=26) groups based on clinical disease severity. Sera were collected and analyzed using ELISA to measure Ascaris and SARS-CoV-2-specific antibodies, while Luminex was used to assess cytokines and SARS-CoV-2-specific neutralizing antibody expression.
RESULTS AND DISCUSSION
The results demonstrated that asymptomatic SARS-CoV-2 seropositive individuals expressed, on average, 1.7 and 2.2-times higher levels of Ascaris antibodies compared to individuals with mild and severe COVID-19, respectively. This finding suggests an inverse correlation between Ascaris antibody levels and COVID-19 severity. Notably, logistic regression analysis showed that Ascaris seropositivity was significantly associated with a reduced risk of severe COVID-19 (OR = 0.277, p = 0.021). Interestingly, COVID-19 patients with comorbidities such as type 2 diabetes and high blood pressure showed lower expression of Ascaris antibodies. Strikingly, no correlation was observed between Ascaris antibody levels and SARS-CoV-2-specific neutralizing antibodies. On the other hand, individuals seronegative for Ascaris displayed significantly higher levels of systemic pro-inflammatory markers compared to seropositive individuals. These findings suggest that higher expression of Ascaris antibodies is associated with asymptomatic SARS-CoV-2 infections and may contribute to the reduction of the risk to develop severe COVID-19. The beneficial effect of Ascaris seropositivity on COVID-19 outcomes in Benin may be attributed to a decrease in comorbidities and pro-inflammatory markers. These observations provide valuable insights into the milder COVID-19 trajectory observed in Africa and may have implications for future therapeutic strategies.
Topics: Humans; Animals; Ascaris lumbricoides; Benin; COVID-19; Diabetes Mellitus, Type 2; Pandemics; SARS-CoV-2; Ascaris; Antibodies, Neutralizing; Antibodies, Viral
PubMed: 37622109
DOI: 10.3389/fimmu.2023.1233082 -
Helminthologia Jun 2022This study identified helminthic species among wild boars () in Primorsky Krai, Russia. In total, 66 fecal samples were taken from wild boars and examined using the...
This study identified helminthic species among wild boars () in Primorsky Krai, Russia. In total, 66 fecal samples were taken from wild boars and examined using the floatation-sedimentation method to identify helminths eggs and protozoan cysts. Age and sex were estimated for each host animal investigated. The helminthic fauna of the wild boars examined involved six parasite genera, but 4 are helminths and 2 are protozoans: the nematodes ., , . and ; and the protozoan parasites sp. and . The most prevalent parasite was spp. (13.6 %) followed by (7.6 %). The other parasites found were sp. (3 %), (3 %), sp. (1.5 %) and (1.5 %). Not found positive correlation between the host's age and sex and the parasite prevalence. This was the first detailed study on helminths infections among wild boars in Primorsky Krai.
PubMed: 36118365
DOI: 10.2478/helm-2022-0018 -
Molecular and Biochemical Parasitology Oct 2019The gastrointestinal (GI) tract of vertebrates is inhabited by a vast array of organisms, i.e., the microbiota and macrobiota. The former is composed largely of... (Review)
Review
The gastrointestinal (GI) tract of vertebrates is inhabited by a vast array of organisms, i.e., the microbiota and macrobiota. The former is composed largely of commensal microorganisms, which play vital roles in host nutrition and maintenance of energy balance, in addition to supporting the development and function of the vertebrate immune system. By contrast, the macrobiota includes parasitic helminths, which are mostly considered detrimental to host health via a range of pathogenic effects that depend on parasite size, location in the GI tract, burden of infection, metabolic activity, and interactions with the host immune system. Sharing the same environment within the vertebrate host, the GI microbiota and parasitic helminths interact with each other, and the results of such interactions may impact, directly or indirectly, on host health and homeostasis. The complex relationships occurring between parasitic helminths and microbiota have long been neglected; however, recent studies point towards a role for these interactions in the overall pathophysiology of helminth disease, as well as in parasite-mediated suppression of inflammation. Whilst several discrepancies in qualitative and quantitative modifications in gut microbiota composition have been described based on host and helminth species under investigation, we argue that attention should be paid to the systems biology of the gut compartment under consideration, as variations in the abundances of the same population of bacteria inhabiting different niches of the GI tract may result in varying functional consequences for host physiology.
Topics: Ancylostomatoidea; Animals; Ascaris; Gastrointestinal Tract; Helminths; Host-Parasite Interactions; Humans; Immunity, Mucosal; Intestinal Mucosa; Intestine, Large; Intestine, Small; Lactobacillus; Microbiota; Nematoda; Platyhelminths; Schistosoma; Stomach; Strongyloides stercoralis; Trematoda; Trichuris
PubMed: 31541662
DOI: 10.1016/j.molbiopara.2019.111222 -
Microbial Pathogenesis Feb 2020There are numerous epidemiological and experimental evidences to suggest that Ascaris lumbricoides infection is a neglected risk factor for development of asthma. For... (Review)
Review
There are numerous epidemiological and experimental evidences to suggest that Ascaris lumbricoides infection is a neglected risk factor for development of asthma. For this purpose, we conducted a systematic review and meta-analysis for better understanding of this relationship. Systematic searching (PubMed, Scopus, Web of Science and Google Scholar) was done, up to September 30, 2019 to identify the relevant studies. We applied random-effects meta-analysis model to generate the overall odds ratio (OR) and 95% confidence intervals (CIs). Heterogeneity was assessed with I and τ statistic. Finally, 19 studies (totally 25 datasets), including 14 datasets with microscopic methods (1830 asthmatic patients (APs) and 3802 healthy controls (HCs)) and 11 datasets with serological methods (1543 APs and 3507 HCs) met the eligibility criteria. Considering to the serological methods, our results demonstrated that the APs had higher seroprevalence rate of A. lumbricoides (48.3% vs. 35.1%) than HCs, showing a significant association (pooled crude OR, 1.53; 95%CI, 1.07-2.18). Moreover, microscopic methods showed a higher prevalence of A. lumbricoides infection in the APs compared to the HCs (37.2% vs. 30.2%), but no significant association was found between APs and HCs (pooled crude OR, 1.19; 95%CI, 0.92-1.55). After adjustment for confounders, results showed no significant association for both serological (pooled adjusted OR, 1.43; 95%CI, 0.93-2.19) and microscopic (pooled adjusted OR, 1.05; 95%CI, 0.78-1.42) methods. Despite heterogeneous results, accurate and better quality studies are needed to determine the effect of A. lumbricoides infection on induction or exacerbation of asthma.
PubMed: 32101769
DOI: 10.1016/j.micpath.2020.104099 -
Frontiers in Pediatrics 2022The identification of gene-environment interactions allows the recognition of groups with higher risk of morbidity. This study evaluated the interaction between the...
INTRODUCTION
The identification of gene-environment interactions allows the recognition of groups with higher risk of morbidity. This study evaluated the interaction between the presence of TLR4 gene polymorphisms and infection with severe bronchiolitis in a tropical Colombian region.
METHODS
We included all infants younger than 24 months hospitalized due to bronchiolitis in Hospital centers in the county of Rionegro, Colombia. To identify interaction between severe bronchiolitis and presence of TLR4 polymorphisms and infection, we used log-binomial regression.
RESULTS
Four hundred and seventeen infants were hospitalized due to bronchiolitis, of which 115 (27%) had severe bronchiolitis. In infants with respiratory syncytial virus (RSV) acute infection and positive anti-Ascaris IgE, TLR4 Asp299Gly was associated to low risk of severe bronchiolitis (OR 0.09, CI 95% 0.01-0.48). Conversely, in infants RSV negative with negative anti-Ascaris IgE, TLR4 Asp299Gly was associated with an increased risk of severe bronchiolitis (OR 14.5, CI 95% 2.2-96).
CONCLUSION
In our population there is an interaction between the presence of severe bronchiolitis, TLR4 Asp299Gly and Ile399Thr polymorphisms, anti-Ascaris IgE levels and RSV. This association should be evaluated in other populations to elucidate its role in the pathogenesis of severe bronchiolitis.
PubMed: 35573947
DOI: 10.3389/fped.2022.876882