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International Journal For Parasitology.... Aug 2023Reports of anthelmintic resistance in Ancylostoma caninum are increasing in frequency in the United States of America (USA). In the last few years in vitro and in vivo... (Review)
Review
Reports of anthelmintic resistance in Ancylostoma caninum are increasing in frequency in the United States of America (USA). In the last few years in vitro and in vivo studies characterized individual isolates, demonstrating multiple anthelmintic drug resistance (MADR). In 2021, the American Association of Veterinary Parasitologists initiated a hookworm task force to address this issue. The first report of drug resistant A. caninum occurred in 1987 in Australian racing Greyhounds. In the last five years multiple case reports and investigations show drug resistant A. caninum is becoming a much greater problem in the USA and now extends beyond racing Greyhounds into the general companion animal dog population. The literature, regarding drug resistance in livestock and equine nematodes, provides helpful guidance along with diagnostic methods to better understand the evolution and selection of canine MADR hookworms; however, there are limitations and caveats due to A. caninum's unique biology and zoonotic potential. Mass drug administration (MDA) of anthelminthic drugs to humans to reduce morbidity associated with human hookworms (Necator americanus) should consider the factors that contributed to the development of MADR A. caninum. Finally, as Greyhound racing undergoes termination in some regions and the retired dogs undergo subsequent rehoming, drug resistant parasites, if present, are carried with them. Drug resistant A. caninum requires greater recognition by the veterinary community, and small animal practitioners need to be aware of the spread into current pet dog populations. The current understanding of anthelmintic resistance, available treatments, and environmental mitigation for these drug resistant A. caninum isolates must be monitored for horizontal spread. A major goal in this emerging problem is to prevent continued dissemination.
Topics: Animals; Dogs; Horses; Humans; Ancylostoma; Ancylostomiasis; Dog Diseases; Australia; Anthelmintics; Ancylostomatoidea
PubMed: 37229949
DOI: 10.1016/j.ijpddr.2023.04.003 -
Medical Science Monitor : International... Mar 2024BACKGROUND Ancylostoma spp., including A. duodenale, A. braziliense, A. caninum, and A. ceylanicum, are hookworms that are transmitted from infected soil and by contact...
BACKGROUND Ancylostoma spp., including A. duodenale, A. braziliense, A. caninum, and A. ceylanicum, are hookworms that are transmitted from infected soil and by contact with domestic animals and rodent hosts, and can cause systemic disease and cutaneous larva migrans. The objective of this study was to describe the ecoepidemiology of Ancylostoma caninum and Ancylostoma spp. in urban-marginal sectors and in rural sectors located in Ecuador. MATERIAL AND METHODS Through addressed sampling, a total of 498 domestic dogs and 40 synanthropic rodents were analyzed via the following coproparasitic methods: direct, flotation, sedimentation with centrifugation using saline (egg identification), modified Baermann (larval identification), and morphometric methods (confirmation). A total of 236 people were surveyed, and a clinical analysis was performed via physical examination. The environmental variables were obtained through reports from the INAMHI of Ecuador and the use of online environmental programs. Through surveys, data related to social determinants were obtained. Epidemiological indicators (prevalence, morbidity, and mortality) were obtained through microbial analysis and surveys. RESULTS A total of 250 domestic dogs were diagnosed with Ancylostoma caninum (50, 20%), and 41 were diagnosed with Ancylostoma spp. (8.23%). One synanthropic rodent (2.5%) was positive for A. caninum. In the clinical analysis, 3 patients were identified as positive (1.27%) for cutaneous larva migrans (CLM). Likewise, environmental variables and social determinants influence the transmission, prevalence, and nature of parasitism by hookworm. CONCLUSIONS People, domestic dogs, and rodents were infected with these parasites. Consequently, there is a risk of ancylostomiasis and cutaneous larvae migrans spreading.
Topics: Humans; Animals; Dogs; Ancylostoma; Larva Migrans; Ecuador; Prevalence; Larva; Feces
PubMed: 38500436
DOI: 10.12659/MSM.943931 -
Veterinary Parasitology, Regional... Jul 2024Ancylostoma caninum is a widely prevalent parasitic nematode in dogs across the world. There has been a notable increase in reports of anthelmintic resistance in A....
Surveillance of Ancylostoma caninum in naturally infected dogs in Quebec, Canada, and assessment of benzimidazole anthelmintics reveal a variable efficacy with the presence of a resistant isolate in imported dogs.
Ancylostoma caninum is a widely prevalent parasitic nematode in dogs across the world. There has been a notable increase in reports of anthelmintic resistance in A. caninum within the United States of America in recent years, which has led us to investigate the potential of this scenario in Canada. The study objectives were to assess the prevalence of A. caninum in two different groups, including a colony of rescued dogs in Canada and three imported Greyhound dogs from USA, and to evaluate the efficacy of two benzimidazole (BZ) anthelmintics against A. caninum, complemented with a molecular genetic analysis adapted to low prevalence. Fecal samples were collected at pre- and post-treatment with fenbendazole for the native shelters-origin group, and a combination of anthelmintic formulations, including the pro-BZ febantel for the USA-origin group. The coprology analyses found several genera of internal parasites. Canine ancylostomiasis was the most prevalent parasitosis with 30.77% in the native group and 100% in the USA group, but with overall low average of A. caninum eggs per gram. Through the fecal egg count reduction test (FECRT), applying a cut-off at 90% as baseline of egg reduction for successful efficacy, BZ showed variable efficacy. Furthermore, molecular analysis confirmed the presence of A. caninum in both groups of dogs and found differences in the genetics linked to BZ resistance on the A. caninum β-tubulin isotype 1 gene. In the isolate from the native group, both codons 167 and 200 were homozygous without the presence of single nucleotide polymorphism (SNP). In contrast, the selected isolate from the USA group, showed a homozygous allele at position 200 and a heterozygous SNP at position 167. The latter was congruent with the low efficacy in FECRT and agrees with the recent findings of USA A. caninum isolate resistant phenotype to the BZ anthelmintics. The limitations of the study include an overall low eggs-per-gram in both canine groups, and the shortage of additional fecal samples from the USA group, restraining the molecular analysis only to one out of the three Greyhounds. This study provided some insights on the efficacy of BZs against A. caninum and revealed the presence of BZ resistant isolates in imported dogs in Quebec, Canada. All this information should be considered, for choosing the best strategy in the control of A. caninum using anthelmintic drugs.
Topics: Animals; Dogs; Dog Diseases; Benzimidazoles; Ancylostoma; Ancylostomiasis; Anthelmintics; Drug Resistance; Feces; Quebec; Prevalence; Female; Male
PubMed: 38880561
DOI: 10.1016/j.vprsr.2024.101036 -
Veterinary Parasitology, Regional... Jun 2024Recent studies demonstrated that Greyhounds are commonly infected with Ancylostoma caninum and these infections have been shown to be resistant to anthelmintics. This...
Recent studies demonstrated that Greyhounds are commonly infected with Ancylostoma caninum and these infections have been shown to be resistant to anthelmintics. This study evaluated samples submitted to a commercial reference laboratory (IDEXX Laboratories) for canine fecal flotation zinc sulfate centrifugation and coproantigen immunoassay between January 1, 2019, and July 30, 2023 for evidence that Greyhounds were more often positive for Ancylostoma spp. (hookworms) compared to other breeds. The purpose of the study was to determine if Greyhounds were more likely to be hookworm-positive compared to other breeds, if Greyhounds on preventives with efficacy against hookworm infections are more likely to test positive than other breeds, if their infections take longer to resolve, to estimate how long this takes and to assess whether the proportion of hookworm positive tests for all breeds is increasing over time. Records of 25,440,055 fecal results were obtained representing 17,671,724 unique dogs. Of these, 49,795 (∼0.3%) were Greyhounds. The overall odds ratio (OR) of 15.3 (p < 0.001) suggests that Greyhounds are at significantly higher risk than other breeds for hookworm positive float findings, and the OR of 14.3 (p < 0.001) suggests significantly higher risk for hookworm antigen positive results. The median time to negative testing event from the Turnbull distribution estimate was in the interval of 1-2 days for other breeds and 71-72 days for Greyhounds. These results provide evidence that anthelmintic resistant A. caninum strains may be having population-level impacts on the frequency and duration of infections in Greyhounds. The findings have broader health implications beyond Greyhounds as MADR A. caninum strains could spread to other breeds and even pet owners.
Topics: Animals; Dogs; Dog Diseases; Feces; Retrospective Studies; Ancylostoma; Hookworm Infections; Immunoassay; Ancylostomiasis; Antigens, Helminth; Female; Male
PubMed: 38772642
DOI: 10.1016/j.vprsr.2024.101026 -
Emerging Infectious Diseases Jun 2024Ancylostoma ceylanicum is the second most common hookworm infecting humans in the Asia-Pacific region. Recent reports suggest presence of the parasite in the Americas....
Ancylostoma ceylanicum is the second most common hookworm infecting humans in the Asia-Pacific region. Recent reports suggest presence of the parasite in the Americas. We report A. ceylanicum infections in coyotes from the Guanacaste Conservation Area, Costa Rica. Our findings call for active surveillance in humans and animals.
Topics: Costa Rica; Animals; Ancylostomiasis; Ancylostoma; Zoonoses; Coyotes; Humans
PubMed: 38782140
DOI: 10.3201/eid3006.231618 -
The American Journal of Tropical... Mar 2024Zoonotic human infections with Ancylostoma ceylanicum have recently been reported in the Americas. We used archived human stool samples to study the geographic...
Geographic Distribution of Human Infections with Zoonotic Ancylostoma ceylanicum and Anthropophilic Hookworms in Ecuador: A Retrospective Analysis of Archived Stool Samples.
Zoonotic human infections with Ancylostoma ceylanicum have recently been reported in the Americas. We used archived human stool samples to study the geographic distribution of human infections with A. ceylanicum and anthropophilic hookworms in different geoclimatic regions (coastal, Andean, and Amazon) of Ecuador. We analyzed retrospectively archived human stool samples from five studies previously screened for hookworm infection by microscopy, of which four included hookworm-positive samples only and one involved hookworm-negative samples to increase geographic distribution of sampling. Stools were analyzed using multi-parallel quantitative polymerase chain reaction (qPCR) assays to detect Necator americanus, Ancylostoma duodenale, A. ceylanicum, Ascaris lumbricoides, Trichuris trichiura, and Strongyloides stercoralis. Sequencing was done for the A. ceylanicum cox1 gene. A total of 132 samples were analyzed, of which 69 (52.3%) were from hookworm-positive and 63 (47.7%) from hookworm-negative individuals by microscopy. Overall, 82.6% of microscopy-positive samples and 33.3% of microscopy-negative samples were positive for hookworm by qPCR. Of microscopy-positive samples, 36.2% were A. ceylanicum, 37.7% A. duodenale, and 33.3% N. americanus, whereas equivalent proportions for microscopy-negative samples were 1.6%, 31.7%, and 1.6%, respectively. Ancylostoma duodenale was the most widely dispersed geographically, followed by N. americanus. Ancylostoma ceylanicum was least dispersed but was detected in coastal and Amazon regions. In conclusion, human infections with A. ceylanicum, A. duodenale, and N. americanus were detected in different geoclimatic regions of Ecuador. Additional studies are required to further define the epidemiology of human A. ceylanicum infections, but the potentially widespread presence of this helminth in human populations in Ecuador has implications for hookworm control strategies.
Topics: Animals; Humans; Ancylostoma; Ancylostomatoidea; Ancylostomiasis; Retrospective Studies; Ecuador; Hookworm Infections; Zoonoses; Feces
PubMed: 38266286
DOI: 10.4269/ajtmh.23-0469