-
Molecular and Biochemical Parasitology Sep 2019Obesity and ancylostomiasis are considered public health problems. Recent studies have shown that infection by intestinal helminths in obese individuals can ameliorate...
Obesity and ancylostomiasis are considered public health problems. Recent studies have shown that infection by intestinal helminths in obese individuals can ameliorate metabolic disorder and improve glucose tolerance by decreasing both insulin resistance and low-intensity inflammation. However, few helminth species have been studied in this context, and some modulation mechanisms still require deeper investigation. Therefore, the present work aimed to investigate the role of experimental infection with Ancylostoma ceylanicum in the modulation of the immune response in an obese experimental model. Four groups of hamsters were used as follows: two groups were submitted to a hyperlipidic and hypercaloric diet capable of inducing obesity, one infected and the other uninfected; and two normonourished control groups, one infected and one uninfected by A. ceylanicum. Biochemical, haematological, parasitological and immunological parameters were evaluated. The results demonstrated that A. ceylanicum infection accentuated weight loss in obese animals compared to normonourished animals. However, obesity reduced the recovery of worms and oviposition of the females, and both infected groups showed decreased levels of haemoglobin, albumin, iron and erythrocytes. Significant relations were observed for pathogenesis in the following cases: infection interfered in lipid metabolism, which increased levels of total cholesterol and triglycerides in the obese group, and caused a decrease in HDL levels in both groups. Obesity led to an increase in glucose levels, and the infection exacerbated this parameter in both the normonourished and obese groups. Inflammation was intensified in obese animals that showed elevated macrophage and neutrophil activation in adipose tissue, enlargement of the spleen and accumulation of lipids in the liver and faeces. Despite the decrease in IFN-γ levels, the infection did not potentiated the expression of the Foxp3, IL-10 and IL-2 transcription factor for any of the infected groups, markers that could positively compensate the host from the damage caused by obesity.
Topics: Ancylostoma; Ancylostomiasis; Animals; Cholesterol; Cricetinae; Female; Glucose; Humans; Interleukin-10; Interleukin-12; Liver; Male; Obesity; Oviposition; Triglycerides
PubMed: 31306675
DOI: 10.1016/j.molbiopara.2019.111200 -
Infectious Diseases of Poverty Jul 2019Baseline mapping of soil-transmitted helminth (STH) infections among school age children (SAC) in 2008-2009 found high or moderate prevalence in 13 of the 14 districts...
BACKGROUND
Baseline mapping of soil-transmitted helminth (STH) infections among school age children (SAC) in 2008-2009 found high or moderate prevalence in 13 of the 14 districts in Sierra Leone. Following these surveys, mass drug administration (MDA) of mebendazole/albendazole was conducted biannually at national level targeting pre-school children (PSC) aged 12-59 months and intermittently at sub-national level targeting SAC. In addition, MDA with ivermectin and albendazole for eliminating lymphatic filariasis (LF) has been conducted nationwide since 2010 targeting individuals over 5 years of age. Each MDA achieved high coverage, except in 2014 when all but one round of MDA for PSC was cancelled due to the Ebola emergency. The objective of the current study was to determine the prevalence and intensity of STH infections among SAC after a decade of these deworming campaigns.
METHODS
Seventy-three schools in 14 districts were purposefully selected, including 39 schools from the baseline surveys, with approximately two sites from each of low, moderate and high prevalence categories at baseline per district. Fresh stool samples were collected from 3632 children aged 9-14 years (male 51%, female 49%) and examined using the Kato Katz technique.
RESULTS
The prevalence of STH infections in Sierra Leone decreased in 2016 compared to 2008: Ascaris lumbricoides 4.4% (95% confidence interval [CI]: 3.7-5.1%) versus 6.6% (95% CI: 0-25%), Trichuris trichiura 0.7% (95% CI: 0.5-1.1%) versus 1.8% (95% CI: 0-30.2%), hookworm 14.9% (95% CI: 13.8-16.1) versus 38.5% (95% CI: 5.4-95.1%), and any STH 18.3% (95% CI:17.0-19.5%) versus 48.3% (CI: 5.4-96.3%), respectively. In 2016, no district had high hookworm prevalence and four districts had moderate prevalence, compared with eight and four districts respectively in 2008. In 2016, the arithmetic mean hookworm egg count in all children examined was light: 45.5 eggs per gram (EPG) of faeces, (95% CI:\ 35.96-55.07 EPG); three (0.08%) children had heavy infections and nine (0.25%) children had moderate infections.
CONCLUSIONS
Sierra Leone has made considerable progress toward controlling STH as a public health problem among SAC. As LF MDA phases out (between 2017 and 2021), transition of deworming to other platforms and water and sanitation strategies need to be strengthened to maintain STH control and ultimately interrupt transmission.
Topics: Adolescent; Ancylostoma; Ancylostomiasis; Animals; Ascariasis; Ascaris lumbricoides; Chemoprevention; Child; Feces; Female; Helminthiasis; Humans; Male; Prevalence; Schools; Sierra Leone; Soil; Trichuriasis; Trichuris
PubMed: 31262367
DOI: 10.1186/s40249-019-0553-5 -
Enfermedades Infecciosas Y... May 2019Infections caused by Strongyloides stercoralis and other soil-transmitted worms such as hookworms (Necator americanus and Ancylostoma duodenale) represent a major...
Infections caused by Strongyloides stercoralis and other soil-transmitted worms such as hookworms (Necator americanus and Ancylostoma duodenale) represent a major problem worldwide, especially in developing areas. They are difficult to suspect clinically since they produce non-specific and often overlapping signs and symptoms. Likewise, their long prepatent periods hamper the detection of parasitic structures. Microscopic diagnosis is still the most commonly used tool in healthcare laboratories but it is still far from being the ideal technique to detect these infections due to its low sensitivity. In addition, these nematodes have strong morphologic similarities and consequently microbiological diagnosis remains a challenge. Serology has made progress in the diagnosis of S. stercoralis infection but this option is not yet available for hookworms. Molecular biology techniques have been shown to slightly increase this lack of sensitivity, but as with other parasitic infections, they are not currently available for use in clinical microbiology laboratories. Supplement information: This article is part of a supplement entitled «SEIMC External Quality Control Programme. Year 2016», which is sponsored by Roche, Vircell Microbiologists, Abbott Molecular and Francisco Soria Melguizo, S.A. © 2019 Elsevier España, S.L.U. and Sociedad Española de Enfermedades Infecciosasy Microbiología Clínica. All rights reserved.
Topics: Ancylostomiasis; Animals; Helminthiasis; Humans; Necator americanus; Necatoriasis; Soil; Strongyloides stercoralis; Strongyloidiasis
PubMed: 31138419
DOI: 10.1016/S0213-005X(19)30178-8 -
Scientific Reports May 2019Hookworms are one of the most prevalent and important parasites, infecting ~500 million people worldwide. Hookworm disease is among the leading causes of iron-deficiency...
Hookworms are one of the most prevalent and important parasites, infecting ~500 million people worldwide. Hookworm disease is among the leading causes of iron-deficiency anemia in the developing world and is associated with significant growth stunting and malnutrition. In humans, hookworms appear to impair memory and other forms of cognition, although definitive data are hard to come by. Here we study the impact of a human hookworm parasite, Ancylostoma ceylanicum, on cognition in hamsters in a controlled laboratory setting. We developed tests that measure long-term memory in hamsters. We find that hookworm-infected hamsters were fully capable of detecting a novel object. However, hookworm-infected hamsters were impaired in detecting a displaced object. Defects could be discerned at even at low levels of infection, whereas at higher levels of infection, hamsters were statistically unable to distinguish between displaced and non-displaced objects. These spatial memory deficiencies could not be attributed to defects in infected hamster mobility or to lack of interest. We also found that hookworm infection resulted in reproducible reductions in diversity and changes in specific taxanomic groups in the hamster gut microbiome. These data demonstrate that human hookworm infection in a laboratory mammal results in a specific, rapid, acute, and measurable deficit in spatial memory, and we speculate that gut alterations could play some role in these cognitive deficits. Our findings highlight the importance of hookworm elimination and suggest that finer tuned spatial memory studies be carried out in humans.
Topics: Ancylostoma; Ancylostomiasis; Animals; Cognition; Cricetinae; Disease Models, Animal; Female; Gastrointestinal Microbiome; Humans; Male; Memory, Long-Term
PubMed: 31133690
DOI: 10.1038/s41598-019-44301-4 -
PLoS Neglected Tropical Diseases Apr 2019Human hookworms (Necator americanus, Ancylostoma duodenale, and Ancylostoma ceylanicum) are intestinal blood-feeding parasites that infect ~500 million people worldwide...
BACKGROUND
Human hookworms (Necator americanus, Ancylostoma duodenale, and Ancylostoma ceylanicum) are intestinal blood-feeding parasites that infect ~500 million people worldwide and are among the leading causes of iron-deficiency anemia in the developing world. Drugs are useful against hookworm infections, but hookworms rapidly reinfect people, and the parasites can develop drug resistance. Therefore, having a hookworm vaccine would be of tremendous benefit.
METHODOLOGY/PRINCIPAL FINDINGS
We investigated the vaccine efficacy in outbred Syrian hamsters of three A. ceylanicum hookworm antigen candidates from two classes of proteins previously identified as promising vaccine candidates. These include two intestinally-enriched, putatively secreted cathepsin B cysteine proteases (AceyCP1, AceyCPL) and one small Kunitz-type protease inhibitor (AceySKPI3). Recombinant proteins were produced in Pichia pastoris, and adsorbed to Alhydrogel. Recombinant AceyCPL (rAceyCPL)/Alhydrogel and rAceySKPI3/Alhydrogel induced high serum immunoglobulin G (IgG) titers in 8/8 vaccinates, but were not protective. rAceyCP1/Alhydrogel induced intermediate serum IgG titers in ~60% of vaccinates in two different trials. rAceyCP1 serum IgG responders had highly significantly decreased hookworm burdens, fecal egg counts and clinical pathology compared to Alhydrogel controls and nonresponders. Protection was highly correlated with rAceyCP1 serum IgG titer. Antisera from rAceyCP1 serum IgG responders, but not nonresponders or rAceyCPL/Alhydrogel vaccinates, significantly reduced adult A. ceylanicum motility in vitro. Furthermore, rAceyCP1 serum IgG responders had canonical Th2-specific recall responses (IL4, IL5, IL13) in splenocytes stimulated ex vivo.
CONCLUSIONS/SIGNIFICANCE
These findings indicate that rAceyCP1 is a promising vaccine candidate and validates a genomic/transcriptomic approach to human hookworm vaccine discovery.
Topics: Amino Acid Sequence; Ancylostoma; Ancylostomiasis; Animals; Antibodies, Helminth; Antigens, Helminth; Antigens, Surface; Cysteine Proteases; Disease Models, Animal; Immunoglobulin G; Intestinal Diseases, Parasitic; Male; Mesocricetus; Recombinant Proteins; Vaccination; Vaccines; Vaccines, Synthetic
PubMed: 31009474
DOI: 10.1371/journal.pntd.0007345 -
Gastroenterology Nursing : the Official... 2019
Topics: Albendazole; Ancylostomiasis; Antifungal Agents; Duodenal Diseases; Emergency Service, Hospital; Endoscopy, Gastrointestinal; Follow-Up Studies; Gastrointestinal Hemorrhage; Humans; Male; Mebendazole; Melena; Middle Aged; Treatment Outcome
PubMed: 30946305
DOI: 10.1097/SGA.0000000000000423 -
Journal of the American Animal Hospital... 2019
Topics: Ancylostoma; Ancylostomiasis; Animals; Anthelmintics; Dog Diseases; Dogs; Drug Combinations; Drug Therapy, Combination; Feces
PubMed: 30870603
DOI: 10.5326/JAAHA-MS-6904 -
The Korean Journal of Parasitology Feb 2019Melting temperature shift (Tm-shift) is a new detection method that analyze the melting curve on real-time PCR thermocycler using SYBR Green I fluorescent dye. To...
Melting temperature shift (Tm-shift) is a new detection method that analyze the melting curve on real-time PCR thermocycler using SYBR Green I fluorescent dye. To establish a Tm-shift method for the detection of Ancylostoma ceylanicum and A. tubaeforme in cats, specific primers, with GC tail of unequal length attached to their 5 ́ end, were designed based on 2 SNP loci (ITS101 and ITS296) of the internal transcribed spacer 1 (ITS1) sequences. The standard curve of Tm-shift was established using the standard plasmids of A. ceylanicum (AceP) and A. tubaeforme (AtuP). The Tm-shift method stability, sensitivity, and accuracy were tested with reference to the standard curve, and clinical fecal samples were also examined. The results demonstrated that the 2 sets of primers based on the 2 SNPs could accurately distinguish between A. ceylanicum and A. tubaeforme. The coefficient of variation (CV) of Tm-values of AceP and AtuP was 0.07% and 0.06% in ITS101 and was 0.06% and 0.08% in ITS296, respectively. The minimum detectable DNA concentration was 5.22×10-6 and 5.28×10-6 ng/μl samples of AceP and AtuP, respectively. The accuracy of Tm-shift method reached 100% based on examination of 10 hookworm DNA samples with known species. In the clinical detection of hookworm in 69 stray cat fecal sample, the Tm-shift detection results were consistent with the microscopic examination and successfully differentiated between the 2-hookworm species. In conclusion, the developed method is a rapid, sensitive and accurate technique and can provide a promising tool for clinical detection and epidemiological investigation of cat-derived hookworms.
Topics: Ancylostoma; Ancylostomiasis; Animals; Cat Diseases; Cats; DNA Primers; DNA, Helminth; DNA, Ribosomal Spacer; Feces; Molecular Diagnostic Techniques; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity; Transition Temperature
PubMed: 30840793
DOI: 10.3347/kjp.2019.57.1.9 -
Parasitology Research Mar 2019Mass drug administration has been implicated as the major cause of drug resistance in nematodes of ruminants. Single-nucleotide polymorphisms (SNPs) at codons 167, 198,...
Albendazole resistance induced in Ancylostoma ceylanicum is not due to single-nucleotide polymorphisms (SNPs) at codons 167, 198, or 200 of the beta-tubulin gene, indicating another resistance mechanism.
Mass drug administration has been implicated as the major cause of drug resistance in nematodes of ruminants. Single-nucleotide polymorphisms (SNPs) at codons 167, 198, and 200 of the beta-tubulin isotype 1 gene are associated with albendazole resistance mechanisms. Although drug resistance is suspected to occur in nematodes of the same order, at present, there is no evidence of a strong correlation between these canonical SNPs and albendazole resistance in hookworms. In the absence of a hookworm strain that is naturally resistant to albendazole, we produced an albendazole-resistant Ancylostoma ceylanicum strain by selective drug pressure. Restriction fragment length polymorphism-PCR (RFLP-PCR) was employed to identify the presence of SNPs previously associated with drug resistance in other nematodes. However, none of the benzimidazole resistance-associated SNPs known in other nematodes were found. A beta-tubulin isotype 1 gene mini-cDNA library was constructed to obtain the complete cDNA gene sequence for the analysis of the entire gene to identify distinct SNPs associated with resistance. Some SNPs were found, but the resulting sequences were not reproducibly detected among the different clones, preventing their association with the resistance mechanism. The parasitological and hematological parameters of the albendazole-resistant strain were characterized and compared to those of the sensitive strain. Although the albendazole-resistant strain was less adapted to its host, with fewer worms recovered, all other parameters analyzed were similar between both strains. The results of the present study indicate that the mechanism of albendazole resistance of the resistant strain described herein must differ from those that have previously been characterized. Thus, new mechanistic studies are needed in the future.
Topics: Albendazole; Ancylostoma; Ancylostomiasis; Animals; Anthelmintics; Benzimidazoles; Cricetinae; Drug Resistance; Female; Polymerase Chain Reaction; Polymorphism, Restriction Fragment Length; Polymorphism, Single Nucleotide; Tubulin
PubMed: 30697644
DOI: 10.1007/s00436-019-06218-9 -
Veterinary Parasitology Jun 2019A new topical formulation of selamectin plus sarolaner (Revolution Plus/Stronghold Plus, Zoetis) was evaluated in the treatment and control of naturally occurring...
Efficacy and safety of a new topical formulation of selamectin plus sarolaner in the treatment and control of natural infections of Ancylostoma tubaeforme and Toxocara cati in cats presented as veterinary patients in the United States.
A new topical formulation of selamectin plus sarolaner (Revolution Plus/Stronghold Plus, Zoetis) was evaluated in the treatment and control of naturally occurring infections of Ancylostoma tubaeforme and Toxocara cati in cats presented as veterinary patients in the United States. Three thousand three hundred three (3303) cats were screened in 25 veterinary practices in 15 states and 153 hookworm-positive cats (A. tubaeforme and/or A. braziliense), mainly from Alabama, Mississippi, Texas, and Hawaii, were identified; 135 cats met all the criteria for enrollment and were included on study. The cats were randomly assigned to treatment with Revolution (at the label dosage, to provide a minimum dosage of 6 mg/kg selamectin) or selamectin plus sarolaner (at a dosage of 6-12 mg/kg plus 1-2 mg/kg, respectively). Treatments were administered at the time of enrollment and repeated 30 days later. Fecal samples were collected for differential fecal egg count prior to the first treatment (Day 0), prior to the second treatment (Day 30), and approximately 30 days later (Day 60). Efficacy was based on the percentage reductions in geometric mean fecal egg count for A. tubaeforme on Day 30 and Day 60 compared with Day 0. Where cats were co-infected with T. cati, efficacy against this species was also evaluated. Efficacy data were evaluated for A. tubaeforme for 40 cats on both Day 30 and Day 60 for the group treated with the selamectin/sarolaner combination and reductions in geometric mean fecal egg counts of 99.4% and 99.7% were demonstrated for Day 30 and Day 60, respectively. For the group treated with selamectin alone, 44 and 40 cats were evaluated and percent reductions for Day 30 and Day 60 were 99.5% and 99.9%, respectively. For T. cati, 14 cats were evaluated in the selamectin/sarolaner-treated group for Day 30 and for Day 60, and the reduction in geometric mean fecal egg count was 100% for both days. There were 11 and 9 cats evaluated for Day 30 and Day 60, respectively, for the selamectin-treated group and the reduction was again 100% for both days. The geometric mean fecal egg counts post-treatment were significantly lower than pre-treatment for both A. tubaeforme and T. cati, for both treatments, and for both periods of interest (P < 0.0001). No serious adverse events related to treatment with either product occurred during the study. Thus, both selamectin alone and the combination product of selamectin/sarolaner were safe and effective when administered on a monthly basis for the treatment and control of natural infections of A. tubaeforme and T. cati. The addition of sarolaner to the formulation did not interfere with the efficacy of selamectin against these nematodes.
Topics: Ancylostoma; Ancylostomiasis; Animals; Antiparasitic Agents; Azetidines; Cat Diseases; Cats; Female; Ivermectin; Male; Random Allocation; Spiro Compounds; Toxocara; Toxocariasis; Treatment Outcome; United States
PubMed: 30470638
DOI: 10.1016/j.vetpar.2018.10.012