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1.
Parasitol Res ; 121(1): 1-10, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34993634

RESUMO

Trichuriasis is one of the most common soil-transmitted helminth (STH) infections, affecting populations globally. The condition is particularly prevalent in tropical and subtropical areas with low levels of sanitation and poor living conditions. The objective of this systematic review and meta-analysis was to evaluate the prevalence of Trichuris trichiura infection in Asia at the country and region level. Multiple databases/academic search engines (Web of Science, PubMed, ProQuest, Scopus, and Google Scholar) were searched for literature on T. trichiura prevalence in Asia published through January 2021. Pooled prevalence was determined using the meta-package in R (version 3.6.1). Out of 13,836 articles, 226 studies (5,439,500 individuals) from 26 countries met the inclusion criteria. Of the 226 studies, 151 were community-based studies that included individuals across the age spectrum, while 75 studies focused on school children (typically in the 5-16 years age range). The overall T. trichiura pooled prevalence was 15.3% (95% CI: 12.4-19.1%), with a pooled prevalence of 13.3% (95% CI: 10.0-17.1%) for the community studies and 20.9% (95% CI: 14.7-27.9%) for the studies only including school children. For studies including all age groups, individuals in the 1-15 years age group had the highest pooled prevalence at 23.4% (95% CI: 1.7-49.4%). There was a significant difference found in overall pooled prevalence by sex (p < 0.001) and community type (rural versus urban) (p < 0.001). Although prevalence appears to be decreasing, study findings suggest that T. trichiura infection continues to be a public health problem in Asia. Therefore, control programs focused on at-risk individuals in endemic areas are needed.


Assuntos
Ascaríase , Helmintíase , Tricuríase , Adolescente , Animais , Ascaríase/epidemiologia , Ascaris lumbricoides , Ásia , Criança , Pré-Escolar , Fezes , Helmintíase/epidemiologia , Humanos , Lactente , Prevalência , Saneamento , Solo , Tricuríase/epidemiologia , Trichuris
2.
Pediatr Clin North Am ; 69(1): 129-139, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34794670

RESUMO

Intestinal nematode infections caused by soil-transmitted helminths (STH), such as the roundworm Ascaris lumbricoides, the whipworm Trichuris trichiura, and the hookworms Ancylostoma duodenale, and Necator americanus, infect more than 1 billion people throughout the world. School-aged children tend to harbor the greatest numbers of intestinal worms, and as a result, experience more adverse health consequences, such as poor growth, anemia, and cognitive decline. Clinicians should maintain a high degree of suspicion in endemic areas when patients present with surgical abdomens, particularly children. Current antihelminthic drugs are moderately effective, but reinfection is possible. Global efforts are needed to eradicate STH infections.


Assuntos
Infecções por Nematoides/tratamento farmacológico , Infecções por Nematoides/epidemiologia , Adolescente , Albendazol/uso terapêutico , Ancylostoma/isolamento & purificação , Anemia/parasitologia , Animais , Anti-Helmínticos/uso terapêutico , Ascaríase/epidemiologia , Ascaris lumbricoides/isolamento & purificação , Criança , Pré-Escolar , Feminino , Helmintíase/epidemiologia , Infecções por Uncinaria/epidemiologia , Humanos , Higiene , Lactente , Enteropatias Parasitárias/epidemiologia , Masculino , Necator americanus/isolamento & purificação , Infecções por Nematoides/diagnóstico , Infecções por Nematoides/prevenção & controle , Solo/parasitologia , Tricuríase/epidemiologia , Trichuris/isolamento & purificação
3.
Korean J Parasitol ; 59(4): 393-397, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34470090

RESUMO

Although research conducted in East Asia has uncovered parasite eggs from ancient toilets or cesspits, data accumulated to date needs to be supplemented by more archaeoparasitological studies. We examined a total of 21 soil samples from a toilet-like structure at the Hwajisan site, a Baekje-period royal villa, in present-day Korea. At least 4 species of helminth eggs, i.e., Trichuris trichiura, Ascaris lumbricoides, Clonorchis sinensis, and Trichuris sp. (or Trichuris vulpis) were detected in 3 sediment samples of the structure that was likely a toilet used by Baekje nobles. The eggs of T. trichiura were found in all 3 samples (no. 1, 4, and 5); and A. lumbricoides eggs were detected in 2 samples (no. 4 and 5). C. sinensis and T. vulpis-like eggs were found in no. 5 sample. From the findings of this study, we can suppose that the soil-transmitted helminths were prevalent in ancient Korean people, including the nobles of Baekje Kingdom during the 5th to 7th century.


Assuntos
Aparelho Sanitário , Helmintos , Animais , Ascaris lumbricoides , Humanos , República da Coreia , Solo , Trichuris
4.
PLoS Negl Trop Dis ; 15(8): e0009646, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34403424

RESUMO

BACKGROUND: Despite several years of school-based MDA implementation, STH infections remain an important public health problem in Benin, with a country-wide prevalence of 20% in 2015. The DeWorm3 study is designed to assess the feasibility of using community-based MDA with albendazole to interrupt the transmission of STH, through a series of cluster-randomized trials in Benin, India and Malawi. We used the pre-treatment baseline survey data to describe and analyze the factors associated with STH infection in Comé, the study site of the DeWorm3 project in Benin. These data will improve understanding of the challenges that need to be addressed in order to eliminate STH as a public health problem in Benin. METHODS: Between March and April 2018, the prevalence of STH (hookworm spp., Ascaris and Trichuris trichiura) was assessed by Kato-Katz in stool samples collected from 6,153 residents in the community of Comé, Benin using a stratified random sampling procedure. A standardized survey questionnaire was used to collect information from individual households concerning factors potentially associated with the presence and intensity of STH infections in pre-school (PSAC, aged 1-4), school-aged children (SAC, aged 5-14) and adults (aged 15 and above). Multilevel mixed-effects models were used to assess associations between these factors and STH infection. RESULTS: The overall prevalence of STH infection was 5.3%; 3.2% hookworm spp., 2.1% Ascaris lumbricoides and 0.1% Trichuris. Hookworm spp. were more prevalent in adults than in SAC (4.4% versus 2.0%, respectively; p = 0.0001) and PSAC (4.4% versus 1.0%, respectively; p<0.0001), whilst Ascaris lumbricoides was more prevalent in SAC than in adults (3.0% versus 1.7%, respectively; p = 0.004). Being PSAC (adjusted Odds Ratio (aOR) = 0.2, p< 0.001; adjusted Infection Intensity Ratio (aIIR) = 0.1, p<0.001) or SAC (aOR = 0.5, p = 0.008; aIIR = 0.3, p = 0.01), being a female (aOR = 0.6, p = 0.004; aIIR = 0.3, p = 0.001), and having received deworming treatment the previous year (aOR = 0.4, p< 0.002; aIIR = 0.2, p<0.001) were associated with a lower prevalence and intensity of hookworm infection. Lower income (lowest quintile: aOR = 5.0, p<0.001, 2nd quintile aOR = 3.6, p = 0.001 and 3rd quintile aOR = 2.5, p = 0.02), being a farmer (aOR = 1.8, p = 0.02), medium population density (aOR = 2.6, p = 0.01), and open defecation (aOR = 0.5, p = 0.04) were associated with a higher prevalence of hookworm infection. Lower education-no education, primary or secondary school- (aIIR = 40.1, p = 0.01; aIIR = 30.9, p = 0.02; aIIR = 19.3, p = 0.04, respectively), farming (aIIR = 3.9, p = 0.002), natural flooring (aIIR = 0.2, p = 0.06), peri-urban settings (aIIR = 6.2, 95%CI 1.82-20.90, p = 0.003), and unimproved water source more than 30 minutes from the household (aIIR = 13.5, p = 0.02) were associated with a higher intensity of hookworm infection. Improved and unshared toilet was associated with lower intensity of hookworm infections (aIIR = 0.2, p = 0.01). SAC had a higher odds of Ascaris lumbricoides infection than adults (aOR = 2.0, p = 0.01) and females had a lower odds of infection (aOR = 0.5, p = 0.02). CONCLUSION: Hookworm spp. are the most prevalent STH in Comé, with a persistent reservoir in adults that is not addressed by current control measures based on school MDA. Expanding MDA to target adults and PSAC is necessary to substantially impact population prevalence, particularly for hookworm. TRIAL REGISTRATION: ClinicalTrials.gov NCT03014167.


Assuntos
Ascaríase/epidemiologia , Infecções por Uncinaria/epidemiologia , Saneamento , Solo/parasitologia , Tricuríase/epidemiologia , Adolescente , Ancylostomatoidea/isolamento & purificação , Animais , Ascaríase/parasitologia , Ascaríase/transmissão , Ascaris lumbricoides/isolamento & purificação , Benin/epidemiologia , Criança , Pré-Escolar , Características da Família , Fezes/parasitologia , Feminino , Infecções por Uncinaria/parasitologia , Infecções por Uncinaria/transmissão , Humanos , Modelos Logísticos , Masculino , Prevalência , Fatores de Risco , Instituições Acadêmicas , Tricuríase/parasitologia , Tricuríase/transmissão , Trichuris/isolamento & purificação
5.
Parasitol Int ; 85: 102441, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34425258

RESUMO

BACKGROUND: Trichuris suis ova (TSO), with the potential to modulate the human immune system, have been tested for therapeutic application in autoimmune and allergic diseases such as inflammatory bowel disease (IBD). Previous clinical studies were limited to European and American participants, whereas Asian populations have not been well documented. In this study, a clinical trial was conducted to examine the safety and tolerability of TSO administration among a healthy Japanese population. METHODS: The study was a randomized, double-blind, placebo-controlled trial held at Jikei University Hospital, Tokyo. Twelve volunteers were stratified into three groups receiving different doses of TSO (TSO 1000, 2500, and 7500) and another into the control group. These cases were limited to healthy Japanese men aged over 20 years old. Single doses of medicinal TSO or placebo were given to three participants of each group. All participants were followed up to 56 days after ingestion. During the follow-up period, clinical practitioners checked each participant at the clinic at 7, 14, 28, and 56 days post-ingestion (dpi). Clinical symptoms were evaluated using questionnaire-based self-reporting, which participants filled at every visit. Blood samples were drawn at 7, 14, 28, and 56 dpi. Fecal samples were collected at 28 and 56 dpi. RESULTS: During the study period, twelve healthy Japanese male volunteers were enrolled. All participants completed the follow-up period. No severe adverse events were observed during the study period in all groups. Three participants in the TSO 1000, 2500, and 7500 groups had mild to moderate abdominal symptoms, diarrhea, bloating, and appetite loss during the observation period. One participant in the placebo group presented with mild diarrhea. Microscopic examination identified no parasite ova in any fecal samples. Blood sample examination indicated elevated eosinophil count in several cases, especially in the groups with the higher dose of TSO. No extra-abdominal symptoms were present in all cases. CONCLUSIONS: Healthy Japanese people tolerated all doses of TSO without any severe adverse events. On the other hand, mild to moderate abdominal symptoms were observed in several participants. This study suggested that the medicinal use of TSO in Japan is relatively safe, and close follow-up is recommended for sustainable usage.


Assuntos
Doenças Autoimunes/terapia , Hipersensibilidade/terapia , Doenças Inflamatórias Intestinais/terapia , Terapia com Helmintos/efeitos adversos , Trichuris , Adulto , Animais , Doenças Autoimunes/imunologia , Método Duplo-Cego , Humanos , Hipersensibilidade/imunologia , Doenças Inflamatórias Intestinais/imunologia , Japão , Masculino
6.
Parasitol Res ; 120(10): 3619-3624, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34417864

RESUMO

Dogs may serve as hosts for a variety of zoonotic or potentially zoonotic helminths, including Ancylostoma ceylanicum and Trichuris species. Cross-sectional study design was used to collect 210 faecal samples of dogs from Nay Pyi Taw area, Myanmar. According to microscopic examination, 180 samples (85.7%) were positive for eight species of gastrointestinal helminths. Among them, positive rates of Ancylostoma species and Trichuris species eggs were observed as 79.0% (166/210) and 11.9% (15/210), respectively. Molecular identification of A. ceylanicum and Trichuris species was confirmed by COX1 gene- and SSU rRNA gene-targeted PCR. Partial sequences of COX1 and SSU rRNA showed 100% identity with A. ceylanicum, Trichuris trichiura, and Trichuris vulpis deposited in GenBank.


Assuntos
Ancylostoma , Helmintos , Ancylostoma/genética , Animais , Estudos Transversais , Cães , Fezes , Mianmar/epidemiologia , Trichuris/genética
7.
Int J Parasitol ; 51(10): 797-807, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34216623

RESUMO

Parasitic infections can be challenging to study because two dimensional light and electron microscopy are often limited in visualising complex and inaccessible attachment sites. Exemplifying this, Trichuris spp. inhabit a tunnel of epithelial cells within the host caecum and colon. A significant global burden of this infection persists, partly because available anthelminthics lack efficacy, although the mechanisms underlying this remain unknown. Consequently, there is a need to pioneer new approaches to better characterize the parasite niche within the host and investigate how variation in its morphology and integrity may contribute to resistance to therapeutic intervention. To address these aims, we exploited three-dimensional X-ray micro-computed tomography (microCT) to image the mouse whipworm, Trichuris muris, in caeca of wild-type C57BL/6 and SCID mice ex vivo. Using osmium tetroxide staining to effectively enhance the contrast of worms, we found that a subset exhibited preferential positioning towards the bases of the intestinal crypts. Moreover, in one rare event, we demonstrated whipworm traversal of the lamina propria. This morphological variability contradicts widely accepted conclusions from conventional microscopy of the parasite niche, showing Trichuris in close contact with the host proliferative and immune compartments that may facilitate immunomodulation. Furthermore, by using a skeletonization-based approach we demonstrate considerable variation in tunnel length and integrity. The qualitative and quantitative observations provide a new morphological point of reference for future in vitro study of host-Trichuris interactions, and highlight the potential of microCT to characterise enigmatic host-parasite interactions more accurately.


Assuntos
Tricuríase , Trichuris , Animais , Camundongos , Camundongos Endogâmicos C57BL , Camundongos SCID , Membrana Mucosa , Microtomografia por Raio-X
8.
PLoS Pathog ; 17(7): e1009768, 2021 07.
Artigo em Inglês | MEDLINE | ID: mdl-34329367

RESUMO

The intestinal nematode parasite Trichuris muris dwells in the caecum and proximal colon driving an acute resolving intestinal inflammation dominated by the presence of macrophages. Notably, these macrophages are characterised by their expression of RELMα during the resolution phase of the infection. The RELMα+ macrophage phenotype associates with the presence of alternatively activated macrophages and work in other model systems has demonstrated that the balance of classically and alternatively activated macrophages is critically important in enabling the resolution of inflammation. Moreover, in the context of type 2 immunity, RELMα+ alternatively activated macrophages are associated with the activation of macrophages via the IL4Rα. Despite a breadth of inflammatory pathologies associated with the large intestine, including those that accompany parasitic infection, it is not known how colonic macrophages are activated towards an alternatively activated phenotype. Here, we address this important knowledge gap by using Trichuris muris infection, in combination with transgenic mice (IL4Rαfl/fl.CX3CR1Cre) and IL4Rα-deficient/wild-type mixed bone marrow chimaeras. We make the unexpected finding that education of colonic macrophages towards a RELMα+, alternatively activated macrophage phenotype during T. muris infection does not require IL4Rα expression on macrophages. Further, this independence is maintained even when the mice are treated with an anti-IFNγ antibody during infection to create a strongly polarised Th2 environment. In contrast to RELMα, PD-L2 expression on macrophages post infection was dependent on IL4Rα signalling in the macrophages. These novel data sets are important, revealing a surprising cell-intrinsic IL4R alpha independence of the colonic RELMα+ alternatively activated macrophage during Trichuris muris infection.


Assuntos
Colo/imunologia , Colo/parasitologia , Enteropatias Parasitárias/imunologia , Macrófagos/imunologia , Tricuríase/imunologia , Animais , Peptídeos e Proteínas de Sinalização Intercelular/imunologia , Subunidade alfa de Receptor de Interleucina-4/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Trichuris/imunologia
9.
Onderstepoort J Vet Res ; 88(1): e1-e5, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34082536

RESUMO

There are limited data on the efficacy of antiparasitic treatments and husbandry methods to control nematode infections in captive populations of African green monkeys (AGMs), Chlorocebus sabaeus. In faecal egg count (FEC) tests, 10 of the 11 (91%) adult male AGMs captured from the large feral population on the island of St Kitts had evidence of nematode infections, mostly Capillaria (8/11, 73%), Trichuris trichiura (7/11, 64%) and strongylid species (7/11, 64%) specifically (hookworm and Trichostrongylus, 50/50), but also Strongyloides fuelleborni (1/11, 9%). When kept in individual cages with cleaning and feeding regimens to prevent reinfections and treated concurrently with ivermectin (300 µg/kg, given subcutaneously) and albendazole (10 mg/kg, given orally) daily for 3 days, 60% (6/10) of the AGMs were negative at a follow-up FEC at 3 months and by FEC and necropsy at the end of the study 5-8 months later. One monkey appeared to have been reinfected with T. trichiura after being negative by FEC at 3 months post-treatment. Four AGMs were positive for T. trichiura at the 3 month FEC follow-up but were negative at the end of the study after one further treatment regimen. Although initially being cleared of Capillaria following treatment, three AGMs were found to be infected at the end of the study. The ivermectin and albendazole treatment regimen coupled with good husbandry practices to prevent reinfections effectively controlled nematode infections in captive AGMs.


Assuntos
Anti-Helmínticos , Tricuríase , Albendazol/uso terapêutico , Animais , Anti-Helmínticos/uso terapêutico , Chlorocebus aethiops , Fezes , Masculino , Contagem de Ovos de Parasitas/veterinária , Strongyloides , Tricuríase/tratamento farmacológico , Tricuríase/veterinária , Trichuris
10.
PLoS Negl Trop Dis ; 15(6): e0009561, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34191812

RESUMO

BACKGROUND: Preventive chemotherapy is the cornerstone of soil-transmitted helminth (STH) control. Long-term outcomes and adequate treatment frequency of the recently recommended albendazole-ivermectin have not been studied to date. METHODOLOGY/PRINCIPAL FINDINGS: Double-blind randomized controlled trials were conducted in Lao PDR, Pemba Island, Tanzania and Côte d'Ivoire between 2018 and 2020 to evaluate the efficacy and safety of ivermectin-albendazole versus albendazole-placebo in Trichuris trichiura-infected individuals aged 6 to 60. In the framework of this study, in Lao PDR 466 and 413 participants and on Pemba Island, 558 and 515 participants were followed-up six and 12 months post-treatment, respectively. From each participant at least one stool sample was processed for Kato-Katz diagnosis and cure rates (CRs), egg reduction rates (ERRs) and apparent reinfection rates were calculated. If found helminth-positive at six months, participants were re-treated according to their allocated treatment. Long-term outcomes against T. trichiura based on CRs and ERRs of ivermectin-albendazole compared to albendazole were significantly higher at six months in Lao PDR (CR, 65.8 vs 13.4%, difference; 52.4; 95% CI 45.0-60.0; ERRs, 99.0 vs 79.6, difference 19.4; 95% CI 14.4-24.4) and Pemba Island (CR, 17.8 vs 1.4%, difference; 16.4; 95% CI 11.6-21.0; ERRs, 84.9 vs 21.2, difference 63.8; 95% CI 50.6-76.9) and also at 12 months in Lao PDR (CR, 74.0 vs 23.4%, difference; 50.6; 95% CI 42.6-61.0; ERRs, 99.6 vs 91.3, difference 8.3; 95% CI 5.7-10.8) and Pemba Island (CR, 19.5 vs 3.4%, difference; 16.1; 95% CI 10.7-21.5; ERRs, 92.9 vs 53.6, difference 39.3; 95% CI 31.2-47.4) respectively. Apparent reinfection rates with T. trichiura were considerably higher on Pemba Island (100.0%, 95% CI, 29.2-100.0) than in Lao PDR (10.0%, 95% CI, 0.2-44.5) at 12 months post-treatment for participants treated with albendazole alone. CONCLUSIONS/SIGNIFICANCE: The long-term outcomes against T. trichiura of ivermectin-albendazole are superior to albendazole in terms of CRs and ERRs and in reducing infection intensities. Our results will help to guide decisions on how to best use ivermectin-albendazole in the context of large-scale PC programs tailored to the local context to sustainably control STH infections. TRIAL REGISTRATION: ClinicalTrials.gov registered with clinicaltrials.gov, reference: NCT03527732, date assigned: 17 May 2018.


Assuntos
Albendazol/uso terapêutico , Anti-Helmínticos/uso terapêutico , Ivermectina/uso terapêutico , Tricuríase/tratamento farmacológico , Adolescente , Adulto , Animais , Criança , Método Duplo-Cego , Quimioterapia Combinada , Feminino , Helmintíase/prevenção & controle , Helmintos/isolamento & purificação , Humanos , Laos , Masculino , Pessoa de Meia-Idade , Contagem de Ovos de Parasitas , Tanzânia , Resultado do Tratamento , Trichuris/efeitos dos fármacos
11.
Parasitol Res ; 120(7): 2665-2670, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34173878

RESUMO

Four adult female worms of Trichuris were isolated from an individual of the wild blue sheep (Pseudois nayaur) inhabiting the Helan Mountains, China, during an epidemiological survey of this wild ruminant. Although there were some differences among the worms in posterior end (rectum) morphology and egg shape, little information regarding species status could be inferred from their morphology. Phylogenetic trees were constructed based on sequences of the ITS1 segment of ribosomal RNA (rRNA), and the sequences of the four Trichuris specimens from wild blue sheep were divided into two distinct lineages (Clade A and Clade B). The two specimens in Clade A were named Genotype I, and had the closest relationship with Trichuris skrjabini; the two specimens in Clade B were named Genotype II and had the closest genetic relationship with a previously described Trichuris sp. In the two Trichuris genotypes identified in the present study, the 18S fragments (261 to 262 bp) of the newly obtained sequences were found to be highly conserved, with merely one insert mutation of a single nucleotide present. The genetic distance based on ITS1 between members of Clade A, composed of two T. skrjabini individuals and two Genotype I individuals, ranged from 0 to 0.0034. These distances are within the intraspecies variation of Trichuris (0-0.0272), suggesting that the Genotype I individuals infesting the wild blue sheep were T. skrjabini. In Clade B, the newly obtained sequences clustered with Trichuris sp. specimens isolated from ruminants (sheep and black goat) with strong support, and the genetic distance ranged from 0.0068 to 0.017, which is also within the intraspecies variation of Trichuris (0-0.0272). However, the genetic distances between the Clade A and Clade B were 0.0442 to 0.0578, which are higher than the intraspecies distances in Trichuris but lower than the interspecies distances (0.102-0.5078). These results implied that Clade A and Clade B most likely represent two subpopulations of T. skrjabini; however, the possibility that Clade A is T. skrjabini and Clade B is a Candidatus Trichuris could not be excluded.


Assuntos
Ruminantes/parasitologia , Tricuríase/veterinária , Trichuris/isolamento & purificação , Animais , Animais Selvagens , Sequência de Bases , Teorema de Bayes , China/epidemiologia , Sequência Consenso , Feminino , Genótipo , Filogenia , Tricuríase/epidemiologia , Tricuríase/parasitologia , Trichuris/anatomia & histologia , Trichuris/classificação
12.
PLoS Negl Trop Dis ; 15(5): e0009395, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-34038411

RESUMO

BACKGROUND: Monitoring the success of soil-transmitted helminth (STH) control programs relies on accurate diagnosis and quantitative assessment of infection prevalence and intensity. As preventative chemotherapeutic program coverage for STH expands, the necessity of gaining insights into the relative or comparative sensitivities, in terms of limits of detection (LOD) and egg-recovery-rates (ERR) for microscopy and quantitative polymerase chain reaction qPCR-based diagnostic techniques becomes imperative to inform suitability for their intended use for large scale STH monitoring and treatment efficacy studies. METHODOLOGY/PRINCIPAL FINDINGS: The diagnostic performance in terms of ERR and LOD of the Kato-Katz (KK) thick smear technique, sodium nitrate (NaNO3) faecal floatation (FF) and qPCR for the accurate detection and enumeration of STH eggs were calculated and expressed in eggs per gram (EPG), by experimentally seeding parasite-free human faeces with Ascaris spp., Trichuris spp. and Necator americanus eggs representing low, medium and high intensity infections. The efficiency of NaNO3 flotation was also calculated over a range of specific gravities (SpGr) for the optimum recovery of STH eggs. FF of SpGr 1.30 recovered 62.7%, 11% and 8.7% more Trichuris spp., Necator americanus and Ascaris spp. eggs respectively, than the recommended SpGr of 1.20. All diagnostic methods demonstrated strong direct correlation to the intensity of seeded EPG. KK and FF (SpGr 1.30) resulted in significant lower ERRs compared to qPCR (p <0.05). qPCR demonstrated significantly (p <0.05) greater sensitivity with an ability to detect as little as 5 EPG for all three STH, compared to 50 EPG by KK and FF (SpGr 1.30). CONCLUSIONS/SIGNIFICANCE: This study compares the diagnostic parameters in terms of LOD and ERRs of STHs for the KK, FF and qPCR. These results indicate that the diagnostic performance of qPCR assays should be considered by control programs in the phase that aims to seek confirmation of transmission break and cessation of preventive chemotherapy in low-transmission settings, in line with the control targets of the WHO neglected tropical diseases 2030 Roadmap.


Assuntos
Fezes/parasitologia , Helmintíase/diagnóstico , Contagem de Ovos de Parasitas/métodos , Reação em Cadeia da Polimerase em Tempo Real/métodos , Animais , Ascaris/isolamento & purificação , Humanos , Limite de Detecção , Microscopia/métodos , Necator americanus/isolamento & purificação , Nitratos , Prevalência , Sensibilidade e Especificidade , Trichuris/isolamento & purificação
13.
Front Immunol ; 12: 627638, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33936040

RESUMO

Background: Tuberculosis (TB) is still a major challenge for humankind. Because regions with the highest incidence also have a high prevalence of helminthiasis and nutritional scarcity, we wanted to understand the impact of these on TB progression. Methods: We have developed an experimental murine model for active TB in C3HeB/FeJ, coinfected with Trichuris muris and Heligmosomoides polygyrus nematodes, and exposed to an environmental mycobacterium (M. manresensis) and intermittent fasting. Cause-effect relationships among these factors were explored with Partial Least Squares Path modelling (PLSPM). Results: Previous parasitization had a major anti-inflammatory effect and reduced systemic levels of ADA, haptoglobin, local pulmonary levels of IL-1ß, IL-6, TNF-α, CXCL-1, CXCL-5 and IL-10. Oral administration of heat-killed M. manresensis resulted in a similar outcome. Both interventions diminished pulmonary pathology and bacillary load, but intermittent food deprivation reduced this protective effect increasing stress and inflammation. The PLSPM revealed nematodes might have protective effects against TB progression. Conclusions: Significantly higher cortisol levels in food-deprivation groups showed it is a stressful condition, which might explain its deleterious effect. This highlights the impact of food security on TB eradication policies and the need to prioritize food supply over deworming activities.


Assuntos
Coinfecção , Privação de Alimentos , Helmintíase/parasitologia , Enteropatias Parasitárias/parasitologia , Pulmão/microbiologia , Mycobacterium tuberculosis/patogenicidade , Nematospiroides dubius/patogenicidade , Infecções por Strongylida/parasitologia , Tricuríase/parasitologia , Trichuris/patogenicidade , Tuberculose Pulmonar/microbiologia , Fenômenos Fisiológicos da Nutrição Animal , Animais , Citocinas/metabolismo , Modelos Animais de Doenças , Progressão da Doença , Feminino , Helmintíase/imunologia , Helmintíase/metabolismo , Interações Hospedeiro-Parasita , Mediadores da Inflamação/metabolismo , Enteropatias Parasitárias/imunologia , Enteropatias Parasitárias/metabolismo , Pulmão/imunologia , Pulmão/metabolismo , Masculino , Camundongos Endogâmicos C3H , Mycobacterium tuberculosis/imunologia , Nematospiroides dubius/imunologia , Estado Nutricional , Infecções por Strongylida/imunologia , Infecções por Strongylida/metabolismo , Tricuríase/imunologia , Tricuríase/metabolismo , Trichuris/imunologia , Tuberculose Pulmonar/imunologia , Tuberculose Pulmonar/metabolismo
14.
Korean J Parasitol ; 59(2): 149-152, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33951770

RESUMO

Our previous research on coprolite specimens from the mummies of Joseon Dynasty (1392-1910 CE) has revealed various species of parasite eggs. Herein, we added 2 new helminthic cases of human remains from Joseon-period graves in the Republic of Korea (Korea). The organic materials precipitated on the hip bones of 2 half-mummied cases (Goryeong and Gwangmyeong cases) were collected, rehydrated, and examined by a microscope. In the sample from Goryeong-gun (gun=County), ova of Trichuris trichiura, Clonorchis sinensis, and Metagonimus spp. were detected, and eggs of T. trichiura and A. lumbricoides were found from the sample of Gwangmyeong-si (si=City). By adding this outcome to the existing data pool, we confirm our previous estimates of Joseon-period parasite infection rates. The overall rates of A. lumbricoides, T. trichiura, and C. sinensis decreased dramatically from Joseon to the modern period. In Goryeong mummy specimen, we also found Metagonimus spp. eggs that has rarely been detected in archaeological samples so far.


Assuntos
Ascaris lumbricoides/citologia , Múmias/parasitologia , Trichuris/citologia , Animais , Arqueologia , Ascaris lumbricoides/classificação , Ascaris lumbricoides/isolamento & purificação , Clonorchis sinensis/classificação , Clonorchis sinensis/citologia , Clonorchis sinensis/isolamento & purificação , Humanos , Óvulo/classificação , Óvulo/citologia , República da Coreia , Trichuris/classificação , Trichuris/isolamento & purificação
15.
Parasite ; 28: 47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34047694

RESUMO

The standard techniques for diagnosis of human filariasis are the microscopic examination of blood smears or skin biopsies, which are relatively invasive and poorly sensitive at low levels of infection. Recently, filarial DNA has been detected in fecal samples from non-human primates in Central Africa. The aim of this study was to demonstrate proof-of-concept of a non-invasive molecular diagnosis technique for human filariasis by targeting fragments of 12S rDNA, Cox1, ITS1 and LL20-15kDa ladder antigen-gene by conventional PCR in DNA extracted from stool samples of 52 people infected with Mansonella perstans and/or Loa loa. Of these, 10 patients were infected with soil-transmitted helminths (Trichuris trichiura and/or Ascaris lumbricoides), and none were positive for Necator americanus. Interestingly, no filarial gene fragments were detected in the stools of any of the 52 patients. Future studies should evaluate whether a co-infection with soil-transmitted helminths causing gastrointestinal bleeding and likely allowing (micro)filaria exit into the digestive tract, may facilitate the molecular detection of filarial DNA fragments in stool samples.


Assuntos
Helmintos , Solo , Animais , Ascaris lumbricoides/genética , Humanos , Reação em Cadeia da Polimerase , Trichuris/genética
16.
J Am Assoc Lab Anim Sci ; 60(4): 475-483, 2021 07 01.
Artigo em Inglês | MEDLINE | ID: mdl-33972010

RESUMO

Trichuris spp. are common helminths in NHP, and benzimidazoles and avermectins have both been used to treat these intestinal parasites. The current study compared the efficacy of fenbendazole and ivermectin against natural infection of Trichuris spp. in African green monkeys (Chlorocebus sabaeus). Anthelmintic-naive animals (n = 65) were randomly assigned to 4 groups: an untreated control group, and 3 groups treated with either fenbendazole, ivermectin, or both compounds. Fecal samples were collected before treatment and on days 7, 14, 28, and 60 after treatment, and fecal egg counts (FEC) were determined by using fecal flotation. The mean percentages of FEC reduction at day 60 were 100%, 86%, and 100% for treatment with fenbendazole, ivermectin, and both compounds, respectively. Analyzing the time series of FEC by using a Bayesian generalized linear model showed no significant difference in the proportional reduction in FEC among the 3 treatment groups, although all FEC from treated groups were significantly lower than the FEC of the control group. In contrast, the probability of shedding was highest in the ivermectin group and the lowest in the animals treated with both compounds. The probability of shedding differed significantly between the fenbendazole and ivermectin groups and between the ivermectin and combined-treatment groups. In conclusion, both fenbendazole and ivermectin are effective anthelmintics in treating Trichuris spp. infection in African green monkeys. All treatment groups showed significant reductions in FEC when compared with baseline counts and control animals; however, fenbendazole may be more effective than ivermectin when used solely or in combination with other anthelmintic treatments.


Assuntos
Anti-Helmínticos , Fenbendazol , Animais , Barbados , Teorema de Bayes , Chlorocebus aethiops , Fezes , Fenbendazol/uso terapêutico , Ivermectina , Contagem de Ovos de Parasitas/veterinária , Trichuris
17.
ACS Infect Dis ; 7(5): 1260-1274, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33797218

RESUMO

Nine hundred million people are infected with the soil-transmitted helminths Ascaris lumbricoides (roundworm), hookworm, and Trichuris trichiura (whipworm). However, low single-dose cure rates of the benzimidazole drugs, the mainstay of preventative chemotherapy for whipworm, together with parasite drug resistance, mean that current approaches may not be able to eliminate morbidity from trichuriasis. We are seeking to develop new anthelmintic drugs specifically with activity against whipworm as a priority and previously identified a hit series of dihydrobenzoxazepinone (DHB) compounds that block motility of ex vivo Trichuris muris. Here, we report a systematic investigation of the structure-activity relationship of the anthelmintic activity of DHB compounds. We synthesized 47 analogues, which allowed us to define features of the molecules essential for anthelmintic action as well as broadening the chemotype by identification of dihydrobenzoquinolinones (DBQs) with anthelmintic activity. We investigated the activity of these compounds against other parasitic nematodes, identifying DHB compounds with activity against Brugia malayi and Heligmosomoides polygyrus. We also demonstrated activity of DHB compounds against the trematode Schistosoma mansoni, a parasite that causes schistosomiasis. These results demonstrate the potential of DHB and DBQ compounds for further development as broad-spectrum anthelmintics.


Assuntos
Anti-Helmínticos , Brugia Malayi , Nematospiroides dubius , Parasitos , Animais , Anti-Helmínticos/farmacologia , Humanos , Schistosoma mansoni , Trichuris
18.
PLoS One ; 16(4): e0240872, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33882065

RESUMO

Social grooming in the animal kingdom is common and serves several functions, from removing ectoparasites to maintaining social bonds between conspecifics. We examined whether time spent grooming with others in a highly social mammal species was associated with infection status for gastrointestinal parasites. Of six parasites detected, one (Trichuris sp.) was associated with social grooming behaviors, but more specifically with direct physical contact with others. Individuals infected with Trichuris sp. spent significantly less time grooming conspecifics than those not infected, and time in direct contact with others was the major predictor of infection status. One model correctly predicted infection status for Trichuris sp. with a reliability of 95.17% overall when the variables used were time spent in direct contact and time spent grooming others. This decrease in time spent grooming and interacting with others is likely a sickness behavior displayed by individuals with less energy or motivation for non-essential behaviors. This study emphasizes the possible links between host behavior and parasitic infections and highlights the need for an understanding of a study population's parasitic infections when attempting to interpret animal behavior.


Assuntos
Comportamento Animal/fisiologia , Chlorocebus aethiops/fisiologia , Chlorocebus aethiops/parasitologia , Trichuris/patogenicidade , Animais , Criança , Pré-Escolar , Feminino , Asseio Animal/fisiologia , Humanos , Lactente , Enteropatias Parasitárias/parasitologia , Enteropatias Parasitárias/fisiopatologia , Masculino , Reprodutibilidade dos Testes , Comportamento Social , Tricuríase/fisiopatologia
19.
J Helminthol ; 95: e20, 2021 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-33820570

RESUMO

The aim of this study was to explore through cross-sectional study the variation in the prevalence of parasitic helminths in canine faeces collected from green spaces of Buenos Aires according to the human density (HD) and economic level (EL) in the surroundings. HD and EL were considered as independent variables with three categories each. Twenty public squares (one hectare of surface) were randomly selected for each existing combination of the two independent variables. Ten random samples of fresh canine faeces were obtained in each square and analysed for helminths by the sedimentation and flotation techniques. The prevalence for each of the species was analysed using generalized linear models (GLM). The prevalence was modelled with a binomial error distribution and a logit link function. Helminth eggs were detected in 45 out of the 200 (22.5%) faecal samples collected and in 18 of the 20 green spaces sampled. The species observed were Ancylostoma caninum (13% of samples), Trichuris vulpis (8%) and Toxocara canis (4.5%). The GLM indicated that the prevalence of A. caninum in the slum areas (very high HD and very low EL) was higher than that in the other areas studied. However, the HD seemed to contribute more than the EL to the variations in the prevalence of A. caninum in faecal samples. The GLM showed no differences in the prevalence of the other parasite species for the different levels of the independent variables.


Assuntos
Ancylostoma/isolamento & purificação , Doenças do Cão , Enteropatias Parasitárias , Toxocara canis , Trichuris/isolamento & purificação , Animais , Argentina , Estudos Transversais , Doenças do Cão/parasitologia , Cães/parasitologia , Fezes/parasitologia , Humanos , Enteropatias Parasitárias/veterinária , Densidade Demográfica , Prevalência , Toxocara canis/isolamento & purificação
20.
Clin Infect Dis ; 73(7): 1203-1210, 2021 10 05.
Artigo em Inglês | MEDLINE | ID: mdl-33906234

RESUMO

BACKGROUND: The efficacy of currently available anthelminthics against Trichuris trichiura infections is significatively lower than for other soil-transmitted helminths. The combination of ivermectin (IVM) and albendazole (ALB) has shown significant improvements in efficacy. METHODS: Safety and efficacy randomized controlled clinical trial comparing 3 experimental regimens against ALB monotherapy for the treatment of T. trichiura infections in northern Honduras. Infected children were randomized to 4 treatment arms: arm 1, single-dose ALB (400 mg); arm 2, single-dose ALB (400 mg) plus IVM (600 µg/kg); arm 3, ALB (400 mg) for 3 consecutive days; or arm 4, ALB (400 mg) plus IVM (600 µg/kg) for 3 consecutive days. Efficacy was measured based on the egg reduction and cure rates, both assessed 14-21 days after treatment, using the Kato-Katz method. Safety was evaluated by analyzing the frequency and severity of adverse events. RESULTS: Of 176 children randomized to 1 of the 4 treatment arms, 117 completed treatment and follow-up. The egg reduction rates for arms 1, 2, 3, and 4 were 47.7%, 96.7%, 72.1%, and 100%, respectively; with P values <.001 for comparisons between IVM groups and ALB-only arms. The cure rates were 4.2%, 88.6%, 33.3%, and 100%, respectively. A total of 48 adverse events (85.4% mild) were reported in 36 children. CONCLUSIONS: The combined use of ALB and high-dose IVM is a highly effective and well tolerated treatment for the treatment of T. trichiura infections, offering significantly improved treatment for the control of this infection. CLINICAL TRIALS REGISTRATION: NCT04041453.


Assuntos
Anti-Helmínticos , Trichuris , Albendazol/efeitos adversos , Animais , Anti-Helmínticos/efeitos adversos , Criança , Honduras , Humanos , Ivermectina/efeitos adversos , Instituições Acadêmicas
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