Efficacy Of Ivermectin Treatment Research Articles

Effect of sainfoin (Onobrychis viciifolia) on cyathostomin eggs excretion, larval development, larval community structure and efficacy of ivermectin treatment in horses.

Alternative strategies to chemical anthelmintics are needed for the sustainable control of equine strongylids. Bioactive forages like sainfoin (Onobrychis viciifolia) could contribute to reducing drug use, with the first hints of in vitro activity against cyathostomin free-living stages observed in the past. We analysed the effect of a sainfoin-rich diet on cyathostomin population and the efficacy of oral ivermectin treatment. Two groups of 10 naturally infected horses were enrolled in a 78-day experimental trial. Following a 1-week adaptation period, they were either fed with dehydrated sainfoin pellets (70% of their diet dry matter) or with alfalfa pellets (control group) for 21-days. No difference was found between the average fecal egg counts (FECs) of the two groups, but a significantly lower increase in larval development rate was observed for the sainfoin group, at the end of the trial. Quantification of cyathostomin species abundances with an ITS-2-based metabarcoding approach revealed that the sainfoin diet did not affect the nemabiome structure compared to the control diet. Following oral ivermectin treatment of all horses on day 21, the drug concentration was lower in horses fed with sainfoin, and cyathostomin eggs reappeared earlier in that group. Our results demonstrated that short-term consumption of a sainfoin-rich diet does not decrease cyathostomin FEC but seems to slightly reduce larval development. Consumption of dehydrated sainfoin pellets also negatively affected ivermectin pharmacokinetics, underscoring the need to monitor horse feeding regimes when assessing ivermectin efficacy in the field.

Efficacy of Ivermectin Treatment on Disease Progression Among Adults With Mild to Moderate COVID-19 and Comorbidities

Ivermectin, an inexpensive and widely available antiparasitic drug, is prescribed to treat COVID-19. Evidence-based data to recommend either for or against the use of ivermectin are needed. To determine the efficacy of ivermectin in preventing progression to severe disease among high-risk patients with COVID-19. The Ivermectin Treatment Efficacy in COVID-19 High-Risk Patients (I-TECH) study was an open-label randomized clinical trial conducted at 20 public hospitals and a COVID-19 quarantine center in Malaysia between May 31 and October 25, 2021. Within the first week of patients' symptom onset, the study enrolled patients 50 years and older with laboratory-confirmed COVID-19, comorbidities, and mild to moderate disease. Patients were randomized in a 1:1 ratio to receive either oral ivermectin, 0.4 mg/kg body weight daily for 5 days, plus standard of care (n = 241) or standard of care alone (n = 249). The standard of care consisted of symptomatic therapy and monitoring for signs of early deterioration based on clinical findings, laboratory test results, and chest imaging. The primary outcome was the proportion of patients who progressed to severe disease, defined as the hypoxic stage requiring supplemental oxygen to maintain pulse oximetry oxygen saturation of 95% or higher. Secondary outcomes of the trial included the rates of mechanical ventilation, intensive care unit admission, 28-day in-hospital mortality, and adverse events. Among 490 patients included in the primary analysis (mean [SD] age, 62.5 [8.7] years; 267 women [54.5%]), 52 of 241 patients (21.6%) in the ivermectin group and 43 of 249 patients (17.3%) in the control group progressed to severe disease (relative risk [RR], 1.25; 95% CI, 0.87-1.80; P = .25). For all prespecified secondary outcomes, there were no significant differences between groups. Mechanical ventilation occurred in 4 (1.7%) vs 10 (4.0%) (RR, 0.41; 95% CI, 0.13-1.30; P = .17), intensive care unit admission in 6 (2.4%) vs 8 (3.2%) (RR, 0.78; 95% CI, 0.27-2.20; P = .79), and 28-day in-hospital death in 3 (1.2%) vs 10 (4.0%) (RR, 0.31; 95% CI, 0.09-1.11; P = .09). The most common adverse event reported was diarrhea (14 [5.8%] in the ivermectin group and 4 [1.6%] in the control group). In this randomized clinical trial of high-risk patients with mild to moderate COVID-19, ivermectin treatment during early illness did not prevent progression to severe disease. The study findings do not support the use of ivermectin for patients with COVID-19. ClinicalTrials.gov Identifier: NCT04920942.

Evaluation of gastrointestinal nematode infection and levels of anthelmintic resistance in small-holder goat flocks from three villages around Gaborone, Botswana

This study aimed to investigate: 1) gastrointestinal nematode (GIN) infection in goat flocks, and 2) efficacy of ivermectin treatment in three villages around Gaborone, Botswana. A 100 goats randomly selected from 10 smallholder flocks from Modipane (n = 40), Kopong (n= 30), and Gakuto (n= 30) were evaluated for faecal egg count (FEC), body condition (BCS), FAMACHA® scores (FS), and packed cell volume (PCV) and marked for subsequent identification. Thereafter, all adult goats in participating flocks were treated with ivermectin at 5 mg/kg bodyweight. Seventy-four goats that were FEC positive were re-sampled 11 to 14 days later for a faecal egg count reduction test (FECRT). Mean FEC were in the range 67.5±14.2 to 380±50 (Mean ± SEM) eggs per gram (EPG) but varied significantly at 95% confidence level, between villages and between flocks in the same village. In all but one Modipane flock, the BCS was >3 and acceptable. Similarly, only one flock from Kopong had a FS tending to anaemia. All flocks had a mean PCV within the normal range. Notably, the flock with the highest FS had the lowest PCV. Ivermectin was effective except in one flock whose FEC increased post treatment suggesting anthelmintic resistance. In conclusion, GIN infection is common in smallholder goat flocks in Botswana, although there are significant differences in FEC both between villages and between flocks in the same village. Although possible resistance was observed in one flock, the FECRT indicates that ivermectin is still effective in the majority of the flocks.

A lymphatic dwelling filarioid nematode, Rumenfilaria andersoni (Filarioidea; Splendidofilariinae), is an emerging parasite in Finnish cervids.

BackgroundRecent studies revealed expansion of filarioid nematodes into northern Finland. In addition to Setaria tundra, an abundant filarioid, Rumenfilaria andersoni, was found inhabiting the lymphatic vessels of reindeer. Our study explores the dynamics of the rapid geographic expansion of R. andersoni, defining prevalence and density of microfilariae among 4 new cervid host species in Finland while developing a context for host-parasite ecology in Fennoscandia and more broadly in the Arctic and boreal regions.MethodsBlood samples were evaluated for presence of microfilariae from 1576 semi-domesticated reindeer, 8 captive reindeer, and free-ranging cervids including 105 wild forest reindeer, 862 moose, 114 white tailed deer and 73 roe deer in 2003–2006 (−2010). Additionally, the prepatent period and the efficacy of ivermectin treatment were investigated.ResultsRumenfilaria andersoni was found to be a common and abundant parasite in reindeer (0-90%) and wild forest reindeer (41-100%). Also moose (0-12%), white-tailed deer (15-22%) and roe deer (3%) were revealed as definitive hosts. Ivermectin was not effective against adult parasites. The prepatent period was estimated to be about five months.ConclusionsRumenfilaria andersoni was identified in 3 endemic cervid species and the introduced white-tailed deer, all constituting previously unrecognized host species in the Palearctic. Among moose, the prevalence and intensity were substantially lower than levels observed among subspecies of reindeer. White-tailed deer had a relatively high prevalence and density of R. andersoni microfilariae (rmf), whereas our limited data for roe deer indicated that the nematode may not have been abundant. Density and prevalence of rmf in moose and white tailed deer suggests the nematode may be adapted to these species, and that these cervids may be among the primary hosts of R. andersoni and reservoirs for transmission in Finland. Our current data suggest that R. andersoni became established in Finland recently, coincidental with introduction of white-tailed deer from North America in 1935; subsequent invasion and emergence in the past 70–80 years appears driven by climate-related factors. An alternative hypothesis for a temporally deeper occurrence for R. andersoni in Fennoscandia, representing post-Pleistocene range expansion with moose tracking deglaciation, is not firmly supported.

Strongyloides stercoralislarvae excretion patterns before and after treatment

The variability of larval excretion impedes the parasitological diagnosis of Strongyloides stercoralis in infected individuals. We assessed the number of larvae excreted per gram (LPG) stool in 219 samples from 38 infected individuals over 7 consecutive days before and in 470 samples from 44 persons for 21 consecutive days after ivermectin treatment (200 μg kg-1 BW). The diagnostic sensitivity of a single stool sample was about 75% for individuals with low-intensity infections (⩽1 LPG) and increased to 95% for those with high-intensity infections (⩾10 LPG). Doubling the number of samples examined per person increased sensitivity to more than 95%, even for low-intensity infections. There was no indication of a cyclic excretion of larvae. After treatment, all individuals stopped excreting larvae within 3 days. Larvae were not detected during any of the following 18 days (total 388 Baermann and 388 Koga Agar tests). Two stool samples, collected on consecutive days, are recommended in settings where low or heterogeneous infection intensities are likely. In this way, taking into account the possible biological variability in excretion, the efficacy of ivermectin treatment can be assessed as soon as 4 days after treatment.

Efficacy of Ivermectin Treatment in Elderly Scabies Patients

Efficacy of Ivermectin Treatment in Elderly Scabies Patients

The effect of oral ivermectin on immature ascarids in foals

Summary Orally administered ivermectin a was 100% effective against experimentally induced 11-day-old infections of Parascaris equorum (L3) in 2 trials. In 4 additional trials there was 98% efficacy of ivermectin treatment against induced 28-day-old infections of P. equorum (L4). In 2 trials with natural infections of ascarids, invermectin paste had 93% efficacy against immature P. equorum and 100% efficacy against the adult. One of the latter 2 trials also emphasized the potential problem of reinfection.

Anthelmhntic effects of injectable and oral paste formulations of ivermectin against 28-day infections of parascaris equorum

Summary Efficacy of ivermectin treatment (0.2 mg/kg) against 28-day experimental infections of Parascaris equorum was determined in 18 pony foals6–17.5 weeks old. There were 6 foals in each group: nontreated control, ivermectin injectable or oral paste. In comparison with larvae found in the nontreated controls, ivermectin injectable or paste was 96.0% and 99.9% efficacious. There was a distinct difference in drug effect against the larger (ca 26mm.) vs the smaller (13–19mm) larvae by the 2 formulations of ivermectin. There were no adverse signs related to treatment of the young foals.