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International Journal For Parasitology Jul 2023Hookworms (genera Ancylostoma and Necator) are amongst the most prevalent and important parasites of humans globally. These intestinal parasites ingest blood, resulting...
Hookworms (genera Ancylostoma and Necator) are amongst 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 and recovery of parasites. Here, we describe a robust method for long-term (≥3 year) cryopreservation and recovery of both Ancylostoma and Necator hookworms that is also applicable to two other intestinal parasites that passage through the infective L3 stage, Strongyloides ratti and Heligmosomoides polygyrus bakeri. The key is a revised recovery method, in which cryopreserved L1s are thawed and raised to the infective L3 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.
Topics: Animals; Humans; Dogs; Ancylostomatoidea; Nematoda; Hookworm Infections; Ancylostoma; Intestinal Diseases, Parasitic; Cryopreservation; Mammals
PubMed: 37201563
DOI: 10.1016/j.ijpara.2023.05.001 -
Parasitology Jul 2023Canine soil-transmitted helminths (STHs) cause important zoonoses in the tropics, with varying degrees of intensity of infection in humans and dogs. This study aimed to...
Canine soil-transmitted helminths (STHs) cause important zoonoses in the tropics, with varying degrees of intensity of infection in humans and dogs. This study aimed to investigate the prevalence and associated risk factors for STHs in community dogs residing in Grenada, West Indies. In May 2021, 232 canine fecal samples were examined for zoonotic helminths by microscopy (following flotation), and genomic DNA from a subset of 211 of these samples were subjected to multiplex qPCR for the detection and specific identification of hookworms, spp. and . Microscopic examination revealed that 46.5% (108/232, 95% CI 40–52.9), 9% (21/232, 95% CI 5.35–12.7) and 5.2% (12/232, 95% CI 2.3–8) of the samples contained eggs of spp., spp. and , respectively. Multiplex qPCR revealed that, 42.2% (89/211, 95% CI 35.5–48.8) were positive for at least 1 zoonotic parasite. Of these, 40.8% (86/211, 95% CI 34.1–47.3) of samples tested positive for spp., 36% (76/211, 95% CI 29.5–42.9) were positive for 13.3% (28/211, 95% CI 9–18.6) for , 5.7% for (12/211, 95% CI 2.97–8.81) and 1% (2/211, 95% CI 0–2.26) for spp. (identified as and by conventional PCR-based Sanger sequencing). Using a multiple logistic regression model, a low body score and free-roaming behaviour were significant predictors of test-positivity for these parasitic nematodes in dogs ( < 0.05). Further studies of zoonotic STHs in humans should help elucidate the public health relevance of these parasites in Grenada.
Topics: Animals; Dogs; Humans; Ancylostoma; Dog Diseases; Feces; Grenada; Helminths; Prevalence; Risk Factors; Toxocara; Zoonoses
PubMed: 37184089
DOI: 10.1017/S0031182023000495 -
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 -
Pathogens (Basel, Switzerland) Apr 2023Hookworm infection is one of the most common neglected tropical diseases and is mainly found in tropical and subtropical areas. Two species of human hookworm are...
UNLABELLED
Hookworm infection is one of the most common neglected tropical diseases and is mainly found in tropical and subtropical areas. Two species of human hookworm are distributed in China, i.e., (AD) and (NA).
BACKGROUND
Traditional microscopic technology such as the Kato-Katz method is not suitable for hookworm diagnosis due to the rapid degeneration of fragile hookworm eggs or for species identification of hookworm infection. The aim of the present study was to establish and evaluate a novel nucleic acid detection method based on recombinase-aided isothermal amplification (RAA) for the detection of hookworm infections and species identification.
METHODS
Based on the specific target gene sequences of hookworms ( for AD and for NA, respectively), we designed and synthesized amplification primers and fluorescence probes referring to the principle of the fluorescence recombinase-aided amplification (RAA) technique.
RESULTS
Each assay provided specific amplification of larval DNA from AD and NA by fluorescence RAA, and the detection limits in plasmids reached 10 copies and 10 copies, respectively. Genomic DNA of two hookworm species was successfully detected at a concentration of 0.1 pg/μL, revealing a high detection sensitivity. No positive amplification occurred for genomic DNA from crossed hookworm species and genomic DNA from , , , , , and , revealing a satisfactory specificity. Fecal sample detection results demonstrated a similar efficacy to the Kato-Katz method; however, it had a greater sensitivity than the larvae culture method.
CONCLUSION
A simple and rapid nucleic acid method was successfully established based on RAA, which improved the detection efficacy and species identification for human hookworm infections.
PubMed: 37111516
DOI: 10.3390/pathogens12040630 -
Tropical Medicine and Infectious Disease Mar 2023People can become infected with cutaneous larva migrans (CLM) through skin penetration by the infective zoonotic larvae of hookworms. Few studies have investigated CLM's...
People can become infected with cutaneous larva migrans (CLM) through skin penetration by the infective zoonotic larvae of hookworms. Few studies have investigated CLM's immunodiagnosis, and the existing studies were limited to crude somatic or excretory/secretory antigens (Ags) from adult worms. Here, we aimed to develop an indirect enzyme-linked immunosorbent assay (ELISA) to differentiate and diagnose hwCLM by detecting immunoglobulin (Ig)E, IgG, and IgG subclasses 1-4 (IgG) against the somatic Ag of adult checkerboard titrations of adult worm extract. Pooled serum controls were immunocharacterized using an indirect ELISA. The IgG and IgE results were unsatisfactory; however, the use of total IgG achieved results comparable to those of immunoblotting. Thus, we continued to analyze the IgG-ELISA using serum samples from patients with hwCLM and heterologous infections as well as from healthy controls. The sensitivity and excellent specificity of the total IgG-ELISA were 93.75% and 98.37%, respectively, and its positive and negative predictive values were 75% and 99.67%, respectively. Antibodies from five cases of angiostrongyliasis, gnathostomiasis, and dirofilariasis cross-reacted with the somatic Ag of adult . . This new assay can adequately serodiagnose hwCLM when combined with clinical features and/or histological examination.
PubMed: 37104335
DOI: 10.3390/tropicalmed8040209 -
Veterinary Parasitology, Regional... May 2023Free-roaming dogs are highly exposed to a range of zoonotic parasites, including helminths, which can be transmitted to humans, particularly in rural tropical settings...
Free-roaming dogs are highly exposed to a range of zoonotic parasites, including helminths, which can be transmitted to humans, particularly in rural tropical settings of developing countries. To evidence the diversity and prevalence of gastrointestinal helminths in the stools of free-roaming dogs on the public Pacific coastal beaches of Ecuador, a cross-sectional study was conducted from August 2021 to August 2022. The sampling beaches are located along the tropical Pacific coastal region. Stools were collected from the ground in containers with 10% formalin and processed using the Ritchie method; eggs were identified under a microscope. A total of 573 stools were examined from 20 beaches; the overall prevalence was 157 (27.4%) for one or more helminths. Ten parasites were identified, nine of which are potentially zoonotic. Ancylostoma spp. was the most prevalent (19.4%), followed by Toxocara spp. (7.2%). Trichuris spp., Dipylidium caninum, Diphyllobothrium spp., Capillaria spp., Dicrocoelium spp., Heterobilharzia americana, Hymenolepis spp. and Spirocerca spp. were also observed. Five of them are reported for the first-time infecting dogs in Ecuador. Hence, we evidenced that Ecuadorian beaches are highly contaminated with the dogs' zoonotic gastrointestinal helminths, posing a great risk to public health. Differences in the presence and prevalence were found in samples of tropical humid and dry climate zones. Therefore, based on our findings, we encourage the implementation of broad antiparasitic treatment and prevention strategies to reduce the zoonotic risk.
Topics: Animals; Dogs; Humans; Ecuador; Prevalence; Cross-Sectional Studies; Dog Diseases; Helminths; Parasites
PubMed: 37068862
DOI: 10.1016/j.vprsr.2023.100859 -
Journal of Laboratory Physicians Mar 2023Soil-transmitted helminths (STH) is a major healthcare challenge in the pediatric age group affecting poor and deprived parts of our community. The main species that... (Review)
Review
Soil-transmitted helminths (STH) is a major healthcare challenge in the pediatric age group affecting poor and deprived parts of our community. The main species that infect people are roundworm (AL, ), whipworm (TT, ), and hookworms (HW, and ). We aimed to estimate the pooled prevalence of STH infections in India in the pediatric age group (< 18 years) and assess the risk factors associated with STH in this age group. Three databases were searched (PubMed, Scopus, and Embase) up to February 16, 2021 with deliberate and inclusive search terms for original research articles estimating the prevalence of either of the three STH in India. Data extracted included individual prevalence of the three STH, prevalence of double or triple infections, and associated risk factors. We identified systematically 1,408 publications, of which 44 were included for the final analysis, including studies from 20 states covering 34,590 children. In our study, the prevalence of AL ranged from 0.8 to 91% with a pooled prevalence of 25%, prevalence of TT ranged from 0.3 to 72% with a pooled prevalence of 13%, and for HW prevalence ranged from 0.2 to 80% with pooled prevalence of 10%. Two most important risk factors with higher odds ratio were open defecation practices or open latrine (odds ratio: 5.2) and washing hands without soap using water only (odds ratio: 2.49). Knowledge of areas with high prevalence of STH and associated risk factors would help in designing effective control strategies in the high-risk groups to prevent infection and aid in a drastic reduction of morbidity in children.
PubMed: 37064993
DOI: 10.1055/s-0042-1751319 -
Veterinary World Feb 2023People who used to rear companion animals are healthier than others who do not. Gastrointestinal (GI) helminths are common in cats and serve as reservoirs for zoonotic...
BACKGROUND AND AIM
People who used to rear companion animals are healthier than others who do not. Gastrointestinal (GI) helminths are common in cats and serve as reservoirs for zoonotic diseases. However, the prevalence of GI parasites in cats in Myanmar has never been reported. This study aimed to estimate the prevalence of GI parasites in cats in Myanmar and to identify the potential risk factors associated with GI parasites.
MATERIALS AND METHODS
A total of 230 fecal samples were collected from seven veterinary clinics and two shelters within the Yangon region from January to May 2022. Sampled cats were classified according to age, gender, and the deworming and rearing practices. Fecal samples were analyzed by fecal wet mount, ethyl acetate centrifugal sedimentation, and zinc sulfate centrifugal flotation techniques. Descriptive data were described, and Pearson's χ test was used to identify associated risk factors, such as age, gender, and the deworming and rearing practices.
RESULTS
The overall prevalence of GI parasites was 79.56%, and 57.82% of cats were infected with a diagnostic stage of more than one parasite species. Seven GI parasites were detected, including spp. (55.65%), spp. (46.08%), spp. (20.86%), spp. (11.73%), (7.39%), spp. (4.34%), and spp. (32.17%). Based on statistical analysis, the deworming and rearing practices were significantly associated (p < 0.05) with GI parasitic infections.
CONCLUSION
This study is the first to reveal the prevalence of GI parasites that could assist the need for effective control measures for zoonotic hookworm and roundworm infections in cats. Even with simple microscopic examination, the remarkably high prevalence of GI parasitic infections warrants regular deworming practice. Further molecular studies should also be performed to understand their genetic diversity.
PubMed: 37041997
DOI: 10.14202/vetworld.2023.414-420 -
The Canadian Veterinary Journal = La... Apr 2023The canine hookworm is one of the most prevalent parasitic nematodes in dogs worldwide and has the potential for zoonotic transmission to humans, including the... (Review)
Review
The canine hookworm is one of the most prevalent parasitic nematodes in dogs worldwide and has the potential for zoonotic transmission to humans, including the development of cutaneous larva migrans. Recent confirmation of anthelmintic resistance (AR) in to several anthelmintic classes, mainly in the USA, indicates the potential for this scenario in Canada. We consider various factors that may lead to resistant isolates in Canada, such as the widespread use of antiparasitic drugs without the assessment of efficacy; increased prevalence in various Canadian provinces; and the importation of dogs, mostly from the USA, with a history of persistent infection by . Our objective was to review factors that influence to develop AR and raise awareness regarding the need for a strategic plan to control this parasitic nematode through the appropriate use of anthelmintics.
Topics: Dogs; Animals; Humans; Ancylostoma; Ancylostomatoidea; Ancylostomiasis; Canada; Anthelmintics; Hookworm Infections; Dog Diseases
PubMed: 37008647
DOI: No ID Found