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Parasite Epidemiology and Control Feb 2022is a helminth zoonosis that is estimated to infect more than 100 million dogs and 1 billion people, mostly in the tropics. Humans can be infected by accidentally...
is a helminth zoonosis that is estimated to infect more than 100 million dogs and 1 billion people, mostly in the tropics. Humans can be infected by accidentally ingesting embryonated eggs from the environment or occasionally after ingesting L larvae from paratenic hosts. This study investigated the importance of vertical transmission and the role of puppies in the epidemiology of through the examination of fecal samples from dogs less than one year of age in Grenada, West Indies, a small island tropical developing country. Samples were stored at 4 °C or in 10% formalin until microscopic examination for helminth eggs or using a rapid antigen test for the presence of protozoan species. A knowledge, attitudes and practices study was completed among dog owners, physicians and veterinary students. Of 306 dogs less than one year of age, 147 (48%) were found to have eggs. Vertical transmission was indicated by the proportion of infected dogs increasing from 50% at two weeks of age (from in utero transmission) to 70% by 12 weeks (in utero and lactogenic transmission). After 12 weeks the positivity rate dropped rapidly with no dogs over 40 weeks of age being infected. As eggs were found in puppy feces at two weeks of age, initial treatment of puppies should begin earlier, at twelve days post-partum, than currently recommended to prevent shedding of eggs. Perhaps even more importantly, treatment of pregnant dogs, preventing vertical transmission, would have a major impact on the control of infection. Knowledge of . and other zoonotic helminths such as was found to be low among dog owners, physicians and veterinary students. None of the dog owners treated their dogs for helminths, all were unaware of the risk of zoonoses, and only 9% picked up dog feces. Efforts to prevent vertical transmission and to increase awareness and knowledge of these zoonoses could result in reducing their public health impact.
PubMed: 34917784
DOI: 10.1016/j.parepi.2021.e00232 -
Parasites & Vectors May 2023Few anthelminthics are currently available, manifesting the urgent need for new treatment options. In vitro profiling of current anthelminthics against larval and adult...
BACKGROUND
Few anthelminthics are currently available, manifesting the urgent need for new treatment options. In vitro profiling of current anthelminthics against larval and adult stage helminths displayed varying effects on closely related worm species and between life stages of the same species. Conversely, limited research has been performed on the egg stage of human hookworms, and the effects of investigational compounds on the egg stage are not routinely assessed.
METHODS
We profiled the development and hatching of Heligmosomoides polygyrus, Ancylostoma duodenale and Necator americanus eggs isolated from rodent faeces in liquid media with various nutrient levels, osmolar concentrations, and acidities in dependence on incubation temperature and light exposure. Incubation conditions were optimised to allow the study of drug effect on immature and embryonated eggs. We analysed concentration-effect relationships of commercially available anthelminthics over 72 h.
RESULTS
Rapid embryonation and hatching were observed at room temperature with and without light exposure without nutrient supplementation in a wide range of acidities. Hookworms hatched optimally at room temperature in PBS achieving > 75% hatching over 34 h. Developmental delays were seen when eggs were stored at 4 °C with no effect on viability. Similar delays were also seen with increased osmolar concentrations resulting in decreased viability. Benzimidazole anthelminthics effectively reduced the viability and prevented hatching of hookworm eggs, with albendazole and thiabendazole eliciting particularly potent effects at EC values below 1 µM. Macrolide anthelminthics as well as emodepside, oxantel pamoate, and pyrantel pamoate were inactive while monepantel, levamisole, and tribendimidine displayed varied potencies among the hookworm species.
CONCLUSION
The presented egg-hatching assay will complement ongoing anthelminthic drug discovery and allow a full characterisation of drug activity against all life stages. In the development and application of the egg-hatching assay, good accordance was observed between the three hookworm species evaluated. Marketed anthelminthics show differences of drug action compared to larval and adult stages highlighting the importance of profiling drug activity against all life stages.
Topics: Animals; Adult; Humans; Anthelmintics; Hookworm Infections; Ancylostomatoidea; Albendazole; Necator americanus; Ancylostoma; Larva
PubMed: 37143169
DOI: 10.1186/s13071-023-05771-8 -
Parasite (Paris, France) 2022Eprinomectin and praziquantel, nematodicide and cestodicide compounds, are both combined with the insecticide and acaricide compounds fipronil and (S)-methoprene in...
Efficacy of two endectoparasiticide products combining fipronil and (S)-methoprene or esafoxolaner with eprinomectin and praziquantel against fleas and intestinal helminths in cats naturally infested in Brazil.
Eprinomectin and praziquantel, nematodicide and cestodicide compounds, are both combined with the insecticide and acaricide compounds fipronil and (S)-methoprene in Frontline Protect/Broadline, or esafoxolaner in NexGard Combo. These topical feline endectoparasiticide products were tested for efficacy against fleas and intestinal helminths in a field trial in Brazil. Flea- and/or helminth-infested domestic cats were treated twice at a monthly interval following label instructions: 160 cats with Frontline Protect/Broadline and 165 cats with NexGard Combo. The flea and intestinal helminth infestations were evaluated using comb counts and copromicroscopy, respectively before first treatment for baseline value, then 9 and 30 days after each treatment for fleas, and 9 days after each treatment for helminths. Multiparasitism was very frequent at baseline, as amongst the 325 included cats, 295, 280, 86 and 93 cats were at least infested with Ctenocephalides fleas, Ancylostoma, Toxocara and Dipylidium caninum, respectively. Efficacies were calculated by comparing the geometric means at baseline and at post-treatment timepoints for each parasite genus/species. Inclusive of both products and of all evaluation timepoints, the Ctenocephalides, Ancylostoma, Toxocara and D. caninum efficacies were at least 98.3%, 99.8%, 99.8% and 96.3%, respectively. No adverse reactions were observed, except for a few instances of mild, transient, and self-resolving hypersalivation occurring on the day of treatment in both groups. This field trial demonstrated high-level efficacy of Frontline Protect/Broadline and NexGard Combo against major parasites of cats in Brazil.
Topics: Animals; Brazil; Cat Diseases; Cats; Flea Infestations; Insecticides; Ivermectin; Methoprene; Praziquantel; Pyrazoles; Siphonaptera; Treatment Outcome
PubMed: 35238771
DOI: 10.1051/parasite/2022012 -
International Journal For Parasitology.... Apr 2023Anthelmintic resistance to benzimidazole has been detected in the canine hookworm, Ancylostoma caninum. Benzimidazole resistance is believed to have developed originally...
BACKGROUND
Anthelmintic resistance to benzimidazole has been detected in the canine hookworm, Ancylostoma caninum. Benzimidazole resistance is believed to have developed originally in greyhounds, but has also been detected in non-greyhound pet dogs. The aim of this study was to validate a probe-based allele-specific real-time PCR tests for the F167Y polymorphism on the β-tubulin isotype-1 gene and to determine the geographic distribution.
METHODS
Allele-specific real-time PCR tests were established and validated to detect the codon 167 polymorphism in the Ancylostoma caninum β-tubulin isotype-1gene. Additionally, real-time PCR tests were validated for Ancylostoma spp. and Uncinaria stenocephala. Two nucleic acid extraction protocols were validated including mechanical disruption of parasite structures in stool. The frequency of the F167Y single nucleotide polymorphism (SNP) was determined in hookworm confirmed stool samples. Samples with the resistant 167Y genotype were confirmed by β-tubulin gene sequencing and allele frequencies were determined.
RESULTS
The Ancylostoma spp. and A. caninum F167Y allele-specific real-time PCR tests were highly sensitive and specific when tested against synthetic DNA, spiked samples, and characterized parasites. Using an optimized total nucleic acid extraction protocol, 54 of 511 (10.6%) were found to contain the benzimidazole resistance allele. All 55 samples containing hookworms with the resistance mutation were confirmed by β-tubulin gene sequencing. The majority of resistant hookworms (44 resistant, 183 tested; 24.4%) originated from Florida, five from California (103 tested, 4.9%), three from Idaho (40 tested, 7.5%), two from Nevada (22 tested, 9.1%), and one sample from Hawaii (13 tested, 7.7%). Resistant genotypes were found in 14 different dog breeds including eight in Greyhounds. Allele-frequency determination revealed resistance allele frequencies between 1 and 100% with 58% above 50%.
CONCLUSIONS
This data strongly supports recent findings of benzimidazole resistant canine hookworms present throughout the general US pet dog population.
Topics: Dogs; Animals; Ancylostoma; Parasites; Tubulin; Drug Resistance; Anthelmintics; Benzimidazoles; Hookworm Infections; Ancylostomatoidea; Polymorphism, Single Nucleotide; Real-Time Polymerase Chain Reaction
PubMed: 36958067
DOI: 10.1016/j.ijpddr.2023.01.001 -
Emerging Infectious Diseases Aug 2018During 2012-2015, US-bound refugees living in Myanmar-Thailand border camps (n = 1,839) were surveyed for hookworm infection and treatment response by using quantitative...
During 2012-2015, US-bound refugees living in Myanmar-Thailand border camps (n = 1,839) were surveyed for hookworm infection and treatment response by using quantitative PCR. Samples were collected at 3 time points: after each of 2 treatments with albendazole and after resettlement in the United States. Baseline prevalence of Necator americanus hookworm was 25.4%, Ancylostoma duodenale 0%, and Ancylostoma ceylanicum (a zoonosis) 5.4%. Compared with N. americanus prevalence, A. ceylanicum hookworm prevalence peaked in younger age groups, and blood eosinophil concentrations during A. ceylanicum infection were higher than those for N. americanus infection. Female sex was associated with a lower risk for either hookworm infection. Cure rates after 1 dose of albendazole were greater for A. ceylanicum (93.3%) than N. americanus (65.9%) hookworm (p<0.001). Lower N. americanus hookworm cure rates were unrelated to β-tubulin single-nucleotide polymorphisms at codons 200 or 167. A. ceylanicum hookworm infection might be more common in humans than previously recognized.
Topics: Adolescent; Adult; Aged; Aged, 80 and over; Albendazole; Ancylostoma; Ancylostomiasis; Animals; Anthelmintics; Child; Child, Preschool; Feces; Female; Humans; Infant; Male; Middle Aged; Myanmar; Refugees; Thailand; Young Adult
PubMed: 30014834
DOI: 10.3201/eid2408.180280 -
Pathogens (Basel, Switzerland) Jan 2023The dynamic host-parasite mechanisms underlying hookworm infection establishment and maintenance in mammalian hosts remain poorly understood but are primarily mediated...
The dynamic host-parasite mechanisms underlying hookworm infection establishment and maintenance in mammalian hosts remain poorly understood but are primarily mediated by hookworm's excretory/secretory products (ESPs), which have a wide spectrum of biological functions. We used ultra-high performance mass spectrometry to comprehensively profile and compare female and male ESPs from the zoonotic human hookworm , which is a natural parasite of dogs, cats, and humans. We improved the genome annotation, decreasing the number of protein-coding genes by 49% while improving completeness from 92 to 96%. Compared to the previous genome annotation, we detected 11% and 10% more spectra in female and male ESPs, respectively, using this improved version, identifying a total of 795 ESPs (70% in both sexes, with the remaining sex-specific). Using functional databases (KEGG, GO and Interpro), common and sex-specific enriched functions were identified. Comparisons with the exclusively human-infective hookworm identified species-specific and conserved ESPs. This is the first study identifying ESPs from female and male . The findings provide a deeper understanding of hookworm protein functions that assure long-term host survival and facilitate future engineering of transgenic hookworms and analysis of regulatory elements mediating the high-level expression of ESPs. Furthermore, the findings expand the list of potential vaccine and diagnostic targets and identify biologics that can be explored for anti-inflammatory potential.
PubMed: 36678443
DOI: 10.3390/pathogens12010095 -
Veterinary Parasitology, Regional... Dec 2020Ancylostoma spp. are the most prevalent canine nematode parasites in Brazil. Despite their widespread parasitism in juvenile dogs, infections may occur regardless of...
Ancylostoma spp. are the most prevalent canine nematode parasites in Brazil. Despite their widespread parasitism in juvenile dogs, infections may occur regardless of host age. Although eosinophilia is a frequent finding in experimental infections, it is uncommon in naturally infected dogs. This study aimed to evaluate the prevalence of Ancylostoma spp. and the eosinophil blood counts (EBC) in naturally infected dogs, with or without comorbidities, admitted to the Veterinary Teaching Hospital of the São Paulo State University (UNESP), School of Veterinary Medicine and Animal Science, Botucatu campus, São Paulo state, Brazil, from 2009 to 2018. All retrospective data were gathered from veterinary medical records (VMR); diagnosis of Ancylostoma infection required the identification of eggs in fecal samples by the simple flotation test (SFT). Ancylostoma-infected animals were evaluated for other intestinal parasitic coinfections (IPC) by either the SFT or the centrifugal-flotation test. Dogs free of any gastro-intestinal parasites were prospectively included in control group (Group C). Ancylostoma-infected animals were defined: Ancylostoma spp. only intestinal parasite infection (Group A), Ancyslostoma spp. with concurrent IPC (Group B), Ancylostoma spp. only intestinal parasite infection with concurrent systemic disorders (Group D), and Ancylostoma spp. with both IPC and concurrent systemic disorders (Group E). The overall prevalence of Ancylostoma spp. was 12.1% (207/1715), that was decreased from 2014 to 2018 (9.7%) relative to the 2009-to-2013 period (13.9%). Prevalence was not significantly different between dogs <1-year-old (10.7% [51/478]) and ≥ 1 year-old (11.7% [130/1109]). IPC was observed in 45.4% (93/205) of the animals positive for Ancylostoma spp., while dogs <1 year old experienced IPC more often (58.8% [30/51]) than dogs ≥1 year old (38.5% [50/130]) (P = 0.02). Group A (n = 35) exhibited median EBC of 1.05 × 10/L, and an eosinophilia ratio of 34.3% that was significantly higher (P < 0.05) than Group C (0.45 × 10/L and 4.1%, respectively). Both variables did not differ in Group B (n = 20), D (n = 39) or E (n = 36) in comparison to Group C (P > 0.05). By ROC curve analysis, only Group A generated a significant area under the curve (0.72). With EBC cutoff of 0.85 × 10 eosinophils/L, sensitivity and specificity were 65.7% and 70.8%, respectively. Eosinophil counts alone may be helpful in raising suspicion of an Ancylostoma spp. infection if further intestinal parasites and concurrent disorders are absent. However, local prevalence data and epidemiological findings should also be evaluated, since eosinophilia is less frequently observed with Ancylostoma spp. infections in the presence of comorbidities.
Topics: Ancylostoma; Ancylostomiasis; Animals; Brazil; Dog Diseases; Dogs; Eosinophils; Female; Intestinal Diseases, Parasitic; Leukocyte Count; Male; Prevalence
PubMed: 33308717
DOI: 10.1016/j.vprsr.2020.100452 -
The Korean Journal of Parasitology Dec 2020Human hookworm infections caused by adult Ancylostoma spp. and Necator americanus are one of the most important tropical diseases. We performed a survey of intestinal...
Human hookworm infections caused by adult Ancylostoma spp. and Necator americanus are one of the most important tropical diseases. We performed a survey of intestinal helminths using the Kato-Katz fecal examination technique targeting 1,156 villagers residing in 2 northern provinces (Preah Vihear and Stung Treng) of Cambodia in 2018. The results revealed a high overall egg positive rate of intestinal helminths (61.9%), and the egg positive rate of hookworms was 11.6%. Nine of the hookworm egg positive cases in Preah Vihear Province were treated with 5-10 mg/kg pyrantel pamoate followed by purging with magnesium salts, and a total of 65 adult hookworms were expelled in diarrheic stools. The adult hookworms were analyzed morphologically and molecularly to confirm the species. The morphologies of the buccal cavity and dorsal rays on the costa were observed with a light microscope, and the nucleotide sequences of mitochondrial cytochrome c oxidase subunit 1 (cox1) gene were analyzed. The majority of the hookworm adults (90.7%) were N. americanus, whereas the remaining 9.3% were Ancylostoma ceylanicum, a rare hookworm species infecting humans. The results revealed a high prevalence of hookworm infections among people in a northern part of Cambodia, suggesting the necessity of a sustained survey combined with control measures against hookworm infections.
Topics: Adult; Ancylostoma; Animals; Cambodia; Electron Transport Complex IV; Feces; Female; Hookworm Infections; Humans; Intestinal Diseases, Parasitic; Male; Microscopy; Necator americanus; Pathology, Molecular; Prevalence; Rural Population; Young Adult
PubMed: 33412765
DOI: 10.3347/kjp.2020.58.6.619 -
BioRxiv : the Preprint Server For... Feb 2023Hookworms (genera and ) are amongst of the most prevalent and important parasites of humans globally. These intestinal parasites ingest blood, resulting in anemia,...
Hookworms (genera and ) are amongst of the most prevalent and important parasites of humans globally. These intestinal parasites ingest blood, resulting in anemia, growth stunting, malnutrition, and adverse pregnancy outcomes. They are also critical parasites of dogs and other animals. In addition, hookworms and hookworm products are being explored for their use in treatment of autoimmune and inflammatory diseases. There is thus a significant and growing interest in these mammalian host-obligate parasites. Laboratory research is hampered by the lack of good means of cryopreservation. Here, we describe a robust method for long-term (≥3 year) cryoprotection and recovery of both and hookworms that is also applicable to two other intestinal parasites that passages through the infective third larval stage, and H . The key is the use cryo-preserved first-staged larvae raised to the infective third larval stage using activated charcoal mixed with uninfected feces from a permissive host. This technique will greatly facilitate research on and availability of gastrointestinal parasitic nematodes with great importance to global health, companion animal health, and autoimmune/inflammatory disease therapies.
PubMed: 36778351
DOI: 10.1101/2023.02.01.526637 -
The Brazilian Journal of Infectious... 2021Describe the diagnostic characteristics of a conventional multiplex PCR for the diagnosis of S. stercoralis, N. americanus and Ancylostomas spp.
OBJECTIVES
Describe the diagnostic characteristics of a conventional multiplex PCR for the diagnosis of S. stercoralis, N. americanus and Ancylostomas spp.
METHODS
Fecal samples were collected from a cross-sectional study in Orán department, Salta province, Argentina. The stool samples were analyzed using concentration-sedimentation, Harada Mori, McMaster, and Baermann techniques. DNA was extracted from 50 mg fecal sample using the FastPrep® Spin Kit for Soil. Three pairs of primers were used for the amplification of three products of 101, 330, and 577 base pairs (bp) for S. stercoralis, N. americanus and Ancylostoma spp, respectively. The sensitivity and analytical specificity of multiplex PCR were evaluated, as well as the sensitivity and diagnostic specificity, using a composite standard and Bayesian approach.
RESULTS AND CONCLUSIONS
Multiplex PCR did not present cross-reaction with other intestinal parasites, and the detection limit for multiplex PCR was between 2 and 20 pg of genomic DNA. In addition it presented a diagnostic sensitivity of 97.4% for S. stercoralis and 90.3% for hookworms with a specificity of 100% and 87.6%, respectively. PCR identified a higher proportion (p <0.01) of coinfections (15.3%) than microscopic techniques (3.5%). Also, multiplex PCR showed that there was a positive association between S. stercoralis and hookworms (odds ratio = 2.12). However, this association was due to N. americanus (odds ratio= 3.22), since no association was observed between S. stercoralis and Ancylostoma spp. Neither was an association observed between the two species of hookworms.
Topics: Ancylostomatoidea; Animals; Bayes Theorem; Cross-Sectional Studies; Feces; Humans; Intestinal Diseases, Parasitic; Multiplex Polymerase Chain Reaction; Sensitivity and Specificity; Strongyloides stercoralis; Strongyloidiasis
PubMed: 34774469
DOI: 10.1016/j.bjid.2021.101649