Clinical and Parasitological Evaluation of Ivermectin and Ivermectin + Pyrantel Against Oxyuris Equi in Equines.

The equine pinworm could become an increasingly common problem, as there are reports of failure in the control of this parasite. The aim of this study was to evaluate the effects of ivermectin (IVM) and IVM combined with pyrantel pamoate (PYR). Thirteen parasitological positive equines were treated with oral IVM (200 µg/kg) and therapeutic efficacy, clinical recovery and the egg reappearance period (ERP) were evaluated. In cases for which ERP was shorter than the pre-patent period (PPP), a second treatment was performed with IVM (200 µg/kg) + PYR (6.6 mg/kg), followed by the same evaluation criteria described above. Therapeutic efficacy was 100% with IVM + PYR and 53.84% with IVM. The mean ERP was shorter than the PPP with both formulations, 77.55 days with IVM + PYR and 50 days with IVM. The presence of egg mass was always associated with a least one clinical sign. The reduction in the number of clinical signs per animal from Day 0 to Day 30 was greater in equines treated with IVM + PYR compared to those treated with IVM alone. The animals treated with IVM were 4.5-fold more likely to present clinical signs 30 days after treatment than those treated with IVM+PYR. A negative correlation was found between ERP and the number of clinical signs at 30 days in the animals treated with IVM. This clinical and parasitological evaluation demonstrated that the combination of IVM+PYR was more effective than IVM alone to control Oxyuris equi.

Gastrointestinal helminths in dogs: occurrence, risk factors, and multiple antiparasitic drug resistance.

Helminth infections are detrimental to the overall health of dogs; therefore, this study aimed to identify antiparasitic-resistant helminths and evaluate the infection rate and risk factors for parasitism in canines. For this purpose, a parasitological evaluation of 38 randomly selected animals was performed, followed by the evaluation of the anthelminthic efficacy of three drugs: pyrantel pamoate with praziquantel (Canex Composto®), fenbendazole (Fenzol Pet®), and milbemycin oxime with praziquantel (Milbemax C®). Among the evaluated animals, 22/38 (57.89%) tested negative and 16/38 (42.71%) tested positive for Ancylostoma caninum infection. Evaluation of the efficacy of antiparasitic drugs showed that 12/16 (75%) dogs were infected with helminths that were susceptible to pyrantel pamoate with praziquantel. Among those for which pyrantel pamoate with praziquantel was not effective, 3/4 (75%) were susceptible to fenbendazole, while the remaining case resistant to both pyrantel pamoate with praziquantel and fenbendazole was sensitive to milbemycin oxime with praziquantel (100%). The odds ratio of infection in dogs inhabiting environments containing soil or grass was 6.67 times higher than that in dogs inhabiting impermeable environments. Mixed-breed dogs (SRD) were 6.54 times more likely to be infected compared to purebred dogs. A. caninum resistant to pyrantel pamoate with praziquantel (4/16, 25%) and fenbendazole (1/4, 25%) were detected. The results of this study demonstrated the importance of coproparasitological monitoring by professionals before and after treatments to assess antiparasitic drug effectiveness, ensure animal health and welfare, and minimize animal exposure to risk factors.

Efficacy of nitazoxanide to treat natural Giardia infections in dogs.

BACKGROUND: Giardia parasites cause gastrointestinal disease in humans, dogs, and many other animals worldwide. The treatment of dogs for giardiasis requires further investigation to ascertain levels of drug efficacy and the possibility of adverse side effects. Nitazoxanide (NTZ) has shown good clinical anti-Giardia activity in humans, yet it has not been evaluated for the treatment of giardiasis in dogs. METHODS: Thirty-five dogs, naturally infected with Giardia were divided into five groups (n = 7): dogs in group NTZ1, NTZ2, and NTZ3 were treated with a single oral dose of 37.5 mg/kg, 75 mg/kg, and 150 mg/kg, respectively, of NTZ on days 0 and 14. The fourth group was treated with a commercially available regimen that includes a combination of pyrantel, praziquantel, and febantel (FEB) administered orally for three consecutive days. Additionally, an untreated control group was established. Giardia cysts from the stool of each dog were quantified on days -3, 0, 5, 7, 9, 11, 14, 18, 25, and 28. Biochemical parameters were evaluated in all dogs, before the first treatment and after concluding the experiment. RESULTS: Shedding of Giardia cysts was reduced in all treated groups when compared to untreated controls (P < 0.01). However, NTZ2, NTZ3, and FEB had a lower risk during the study. Furthermore, NTZ was also effective against another protozoan, Cryptosporidium spp. at doses of 75 mg/kg and 150 mg/kg, in contrast to the combination of febantel + pyrantel + praziquantel. Biochemical parameters of treated animals, namely, aspartate transaminase and alanine transaminase enzymes, remained within physiological ranges. CONCLUSIONS: Based on these results, the implementation of NTZ as a treatment for giardiasis in dogs is proposed. The administration of a single dose is an important advantage of NTZ because it reduces workload, particularly in animals placed in shelters and kennels, where handling of large numbers of animals is required, and personnel is frequently scarce.

Efficacy of pyrantel pamoate and ivermectin for the treatment of canine nematodes / Eficácia do pamoato de pirantel e da ivermectina no tratamento de nematódeos caninos

This study evaluated the efficacy of pyrantel pamoate and ivermectin on gastrointestinal nematodes in dogs. Fecal egg counts per gram (EPG) were measured by the fecal egg count reduction test (FECRT) in order to evaluate the anthelmintic efficiency and fecal float exams were also performed to assess the concordance between coproparasitological techniques. A total of 45 naturally infected dogs in the city of Bandeirantes, Paraná State, were selected and divided into three groups: Group 1, 15 animals that received pyrantel pamoate (145 mg) in a single dose; Group 2, 15 animals that received ivermectin (3 mg); and Group 3, 15 animals that comprised an untreated control group. Fecal testing was performed two and 10 days after treatment. Toxocara was the most prevalent genus, followed by Ancylostoma and Trichuris. Ancylostoma had low resistance to ivermectin and pyrantel pamoate treatment, while Toxocara were resistant to both treatments. Statistical correlation testing to compare coproparasitogical techniques revealed moderate concordance, substantial and almost perfect concordance for detection of Ancylostoma, Trichuris, and Toxocara, respectively. The results of this study suggest that the gender Ancylostoma had low resistance and Toxocara is resistant to both drugs and because of their high prevalence in young animals means that others anthelmintic drugs may be recommended to...(AU)

Objetivou-se neste estudo avaliar a eficácia do pamoato pirantel e da ivermectina sobre nematódeos gastrointestinais de cães. Para tanto foram realizados a contagem de ovos nas fezes (OPG) para avaliação da eficiência anti-helmíntica através do Teste de Redução da Contagem de Ovos nas Fezes (RCOF) e exame de flutuação Willis-Mollay para verificação de concordância entre as técnicas coproparasitológicas. Selecionou-se 45 cães na cidade de Bandeirantes, Paraná, naturalmente infectados, os quais foram divididos em três grupos experimentais: Grupo 1, 15 animais que receberam pamoato de pirantel 145 mg; Grupo 2, 15 animais que receberam ivermectina 3 mg e Grupo 3, 15 animais do grupo controle, não tratados. Coletas de fezes foram realizadas dois e dez dias depois para realização dos exames coproparasitológicos. Observou-se que o gênero de maior prevalência foi Toxocara, seguido de Ancylostoma e Trichuris. Ancylostoma apresentou baixa resistência ao tratamento com pamoato de pirantel e ivermectina, e Toxocara foi resistente a ambos os tratamentos. Através de testes de concordância estatística entre as técnicas coproparasitológicas utilizadas, foram constatadas concordâncias moderada, quase perfeita e substancial, respectivamente, na detecção de Ancylostoma, Toxocara e Trichuris. Concluímos neste estudo que o gênero Ancylostoma apresentou baixa resistência e Toxocara é resistente...(AU)

A genetic analysis of Trichuris trichiura and Trichuris suis from Ecuador.

BACKGROUND: Since the nematodes Trichuris trichiura and T. suis are morphologically indistinguishable, genetic analysis is required to assess epidemiological cross-over between people and pigs. This study aimed to clarify the transmission biology of trichuriasis in Ecuador. FINDINGS: Adult Trichuris worms were collected during a parasitological survey of 132 people and 46 pigs in Esmeraldas Province, Ecuador. Morphometric analysis of 49 pig worms and 64 human worms revealed significant variation. In discriminant analysis morphometric characteristics correctly classified male worms according to host species. In PCR-RFLP analysis of the ribosomal Internal Transcribed Spacer (ITS-2) and 18S DNA (59 pig worms and 82 human worms), nearly all Trichuris exhibited expected restriction patterns. However, two pig-derived worms showed a "heterozygous-type" ITS-2 pattern, with one also having a "heterozygous-type" 18S pattern. Phylogenetic analysis of the mitochondrial large ribosomal subunit partitioned worms by host species. Notably, some Ecuadorian T. suis clustered with porcine Trichuris from USA and Denmark and some with Chinese T. suis. CONCLUSION: This is the first study in Latin America to genetically analyse Trichuris parasites. Although T. trichiura does not appear to be zoonotic in Ecuador, there is evidence of genetic exchange between T. trichiura and T. suis warranting more detailed genetic sampling.

Efficacy of pyrantel pamoate and ivermectin for the treatment of canine nematodes / Eficácia do pamoato de pirantel e da ivermectina no tratamento de nematódeos caninos

This study evaluated the efficacy of pyrantel pamoate and ivermectin on gastrointestinal nematodes in dogs. Fecal egg counts per gram (EPG) were measured by the fecal egg count reduction test (FECRT) in order to evaluate the anthelmintic efficiency and fecal float exams were also performed to assess the concordance between coproparasitological techniques. A total of 45 naturally infected dogs in the city of Bandeirantes, Paraná State, were selected and divided into three groups: Group 1, 15 animals that received pyrantel pamoate (145 mg) in a single dose; Group 2, 15 animals that received ivermectin (3 mg); and Group 3, 15 animals that comprised an untreated control group. Fecal testing was performed two and 10 days after treatment. Toxocara was the most prevalent genus, followed by Ancylostoma and Trichuris. Ancylostoma had low resistance to ivermectin and pyrantel pamoate treatment, while Toxocara were resistant to both treatments. Statistical correlation testing to compare coproparasitogical techniques revealed moderate concordance, substantial and almost perfect concordance for detection of Ancylostoma, Trichuris, and Toxocara, respectively. The results of this study suggest that the gender Ancylostoma had low resistance and Toxocara is resistant to both drugs and because of their high prevalence in young animals means that others anthelmintic drugs may be recommended to...

Objetivou-se neste estudo avaliar a eficácia do pamoato pirantel e da ivermectina sobre nematódeos gastrointestinais de cães. Para tanto foram realizados a contagem de ovos nas fezes (OPG) para avaliação da eficiência anti-helmíntica através do Teste de Redução da Contagem de Ovos nas Fezes (RCOF) e exame de flutuação Willis-Mollay para verificação de concordância entre as técnicas coproparasitológicas. Selecionou-se 45 cães na cidade de Bandeirantes, Paraná, naturalmente infectados, os quais foram divididos em três grupos experimentais: Grupo 1, 15 animais que receberam pamoato de pirantel 145 mg; Grupo 2, 15 animais que receberam ivermectina 3 mg e Grupo 3, 15 animais do grupo controle, não tratados. Coletas de fezes foram realizadas dois e dez dias depois para realização dos exames coproparasitológicos. Observou-se que o gênero de maior prevalência foi Toxocara, seguido de Ancylostoma e Trichuris. Ancylostoma apresentou baixa resistência ao tratamento com pamoato de pirantel e ivermectina, e Toxocara foi resistente a ambos os tratamentos. Através de testes de concordância estatística entre as técnicas coproparasitológicas utilizadas, foram constatadas concordâncias moderada, quase perfeita e substancial, respectivamente, na detecção de Ancylostoma, Toxocara e Trichuris. Concluímos neste estudo que o gênero Ancylostoma apresentou baixa resistência e Toxocara é resistente...

Chemometric quality inspection control of pyrantel pamoate, febantel and praziquantel in veterinary tablets by mid infrared spectroscopy.

This paper describes the development and validation of a new multivariate calibration method based on diffuse reflectance mid infrared spectroscopy for direct and simultaneous determination of three veterinary pharmaceutical drugs, pyrantel pamoate, praziquantel and febantel, in commercial tablets. The best synergy interval partial least squares (siPLS) model was obtained by selecting three spectral regions, 3715-3150, 2865-2583, and 2298-1733 cm(-1), preprocessed by first derivative and Savitzky-Golay smoothing followed by mean centering. This model was built with five latent variables and provided root mean square errors of prediction (RMSEP) equal or lower than 0.69 mg per 100 mg of powder for the three analytes. The method was validated according the appropriate regulations through the estimate of figures of merit, such as trueness, precision, linearity, analytical sensitivity, bias and residual prediction deviation (RPD). Then, it was applied to three different veterinary pharmaceutical formulations found in the Brazilian market, in a situation of multi-product calibration, since the excipient composition of these commercial products, which was not known a priori, was modeled by an experimental design that scanned the likely content range of the possible constituents. The results were verified with high performance liquid chromatography with diode array detection (HPLC-DAD) and high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) and were in agreement with the predicted values at 95% confidence level. The developed method presented the advantages of being simple, rapid, solvent free, and about ten times faster than the HPLC ones.

Lagochilascaris minor Leiper, 1909 (Nematoda: Ascarididae) in Mexico: three clinical cases from the Peninsula of Yucatan / Lagochilascaris minor Leiper, 1909 (Nematoda: Ascarididae) en México: tres casos clínicos de la Península de Yucatán

Human lagochilascariasis (HL) is a parasite produced by Lagochilascaris minor Leiper 1909 that also can be found in cats and dogs. HL is considered an emerging zoonosis in the Americas, spreading from Mexico to Argentina, and the Caribbean Islands. The present paper describes three HL cases from the Peninsula of Yucatan, Mexico, recorded in the last decade. It describes the characteristics of the lesions and discusses the route of transmission in humans and particularly in the observed patients.

La Lagochilascariasis humana (HL) es producida por Lagochilascaris minor Leiper, 1909; el cual es un parásito que puede ser encontrado también en gatos y perros. HL es considerada una zoonosis emergente en América distribuida desde México hasta Argentina y las islas del Caribe. El presente artículo describe tres casos de HL en la Península de Yucatán, México registrados en la última década. Se describen las características de las lesiones y se discute la ruta de transmisión en humanos y particularmente en los pacientes observados.

Lagochilascaris minor Leiper, 1909 (Nematoda: Ascarididae) in Mexico: three clinical cases from the Peninsula of Yucatan.

Human lagochilascariasis (HL) is a parasite produced by Lagochilascaris minor Leiper 1909 that also can be found in cats and dogs. HL is considered an emerging zoonosis in the Americas, spreading from Mexico to Argentina, and the Caribbean Islands. The present paper describes three HL cases from the Peninsula of Yucatan, Mexico, recorded in the last decade. It describes the characteristics of the lesions and discusses the route of transmission in humans and particularly in the observed patients.

Pinworm in pregnancy.

A case of enterobiasis in pregnancy that presented as copious nocturnal vaginal discharge is reported. Enterobius vermicularis is the most common parasite infecting humans. Transmission can be fecal-oral or via fomites, and recently arrived immigrants from developing countries and individuals who live in households with young children are particularly at risk. Pinworms are most frequently found in the gastrointestinal tract but can also enter the vagina and bladder. Patients typically present with nocturnal anal itching, and diagnosis can be made by clinical history. Treatment includes an antihelminthic agent for the patient and members of the household as well as home hygiene measures to prevent transmission.

Synergic effect of metronidazole and pyrantel pamoate on Giardia lamblia.

Giardia lamblia is a pathogenic protozoan presenting as the main characteristic, the trophozoite capacity to adhere in host intestinal epithelium, infecting mammals, including humans. The clinical treatment of this disease is based on metronidazole (Mz) that acts as an alternative electron acceptor, and its reduction promotes DNA impairment. In veterinary treatment, one of the best options is pyrantel pamoate (Pm), which the mode of action has not elucidated yet. Different strategies for Giardia treatment have been explored to avoid side effects to the host. In this context, the efficiency of treatment combining drugs raise as an interesting alternative for protozoan diseases. Here, we evaluated in vitro synergic effect of Mz and Pm on trophozoites and on its adherence to IEC-6 cells. The treatment with Mz or Pm was effective on trophozoites, with IC(50)/24h values of 5.3±0.9 µM and 13.8±1.4 µM, respectively. The treatment of trophozoites with different combinations of Mz and Pm were also evaluated, as showed by fractional inhibitory concentration index (FICI) under 0.5 in all conditions tested, corresponding to the synergic effect. This synergic activity was also observed when the combinations of 5.3 µM Mz+0.4 µM Pm and 13.8 µM Pm+0.1 µM Mz induced a remarkable reduction in % adhesion (85-90% and 52-59%, respectively) and in number of adhered parasites per 100 cells. The low cytotoxicity to the host cells of the combinations, associated to the strong synergic potential of the combination, encourage us to further investigate its effect in in vivo models.

Comparison of various anthelmintic therapies for the treatment of Trypanoxyuris microon infection in owl monkeys (Aotus nancymae).

Trypanoxyuris microon is a pinworm that infects New World nonhuman primates, including Aotus nancymae. Although it typically is clinically insignificant, infection may serve as a significant variable during experimental data analysis. In this study we sought to determine the most effective anthelmintic therapy for eradication of T. microon infection in A. nancymae. Animals confirmed to be infected with T. microon by perianal tape test were treated twice (on days 0 and 14) with pyrantel pamoate, ivermectin, or thiabendazole and evaluated for eggs by daily perianal tape test throughout the entire 28-d period. Successful clearance of eggs was defined as 5 consecutive negative perianal tape tests. Pyrantel pamoate and ivermectin were significantly more effective at egg clearance than were thiabendazole and no treatment. Overall, 100% of the pyrantel pamoate and ivermectin treatment groups were cleared of infection after 2 treatments, whereas only 60% of the thiabendazole group became negative for pinworm eggs. In addition, the time after treatment until clearance was 1 to 2 d for pyrantel pamoate, 2 to 4 d for thiabendazole, and 4 to 6.5 d for ivermectin. These results indicate that pyrantel pamoate was the most effective and rapidly acting anthelmintic for the treatment of adult T. microon infection, with ivermectin as a suitable alternative. However because of the potential for continued development of immature stages or reinfection, anthelmintic doses should be repeated after 1 to 2 wk, in combination with effective environmental sanitation.

Ancilostomíase / Ancylostomiasis

A ancilostomíase é uma doença parasitária causada pelos helmintos Ancylostoma duodenale e Necator americanus, com importante.

Utilização de fenbendazole e da associação febantel, pamoato de pirantel e praziquantel no controle de oxiurídeos em gerbis / Use of fenbendazole and the febantel, pamoato of pirantel and praziquantel association in the control of oxiurids in jirds

Eighteen jirds were equally distributed in two treated and one control groups. The commercial products to the fenbendazole base (10mg) and the association of febantel (1.5mg), pirantel (1.44mg) and praziquantel (0.5mg) were orally administred in the concentration of 0.1ml in each group. The effectiveness of febendazole against oxiurids was 81.8 percent, 65.0 and 38.7 percent and for the association of febantel, pirantel and praziquantel was 72.7 percent, 73.8 percent and 51.0 percent on days 7, 14 and 21, respectively. Three applications of that dose of the tested medications, within intervals of 10 days, associated to hygiene, are recommended.

Utilização de fenbendazole e da associação febantel, pamoato de pirantel e praziquantel no controle de oxiurídeos em gerbis / Use of fenbendazole and the febantel, pamoato of pirantel and praziquantel association in the control of oxiurids in jirds

Eighteen jirds were equally distributed in two treated and one control groups. The commercial products to the fenbendazole base (10mg) and the association of febantel (1.5mg), pirantel (1.44mg) and praziquantel (0.5mg) were orally administred in the concentration of 0.1ml in each group. The effectiveness of febendazole against oxiurids was 81.8%, 65.0 and 38.7% and for the association of febantel, pirantel and praziquantel was 72.7%, 73.8% and 51.0% on days 7, 14 and 21, respectively. Three applications of that dose of the tested medications, within intervals of 10 days, associated to hygiene, are recommended.(AU)

Electron and video-light microscopy analysis of the in vitro effects of pyrantel pamoate on Giardia lamblia.

Electron and video-light microscopy analysis of the in vitro effects of pyrantel pamoate on Giardia lamblia. Experimental Parasitology 97, 9-14. Giardia infection is predominant in the small intestine of vertebrates, where the trophozoites attach to epithelial cells and adversely affect the microvilli and other epithelial cell structures. Giardiasis, the disease caused by this protozoan, is very common in developing countries and mainly affects children. Drugs currently used to treat Giardia infection, such as some benzimidazole derivatives, were originally designed to treat helminthic infections. Many of the drugs are known to cause severe side effects and disturbances to the patient. Using transmission electron microscopy and video-light microscopy, we studied the effects of pyrantel pamoate, a drug commonly used in the treatment of helminthic infections in horses and ruminants, on Giardia lamblia trophozoites. Pyrantel pamoate was administered to Giardia cells in four different concentrations. Using video-light microscopy, we observed the decrease in flagella beating frequency and severe changes in the lateral flange and in the general aspect of the cell. Using transmission electron microscopy, we observed changes in the cytoplasm and peripheral vesicles. The flagella and adhesive disk structure were not affected. Apparently, the effects of pyrantel pamoate are irreversible.

Genetic variation in sympatric Ascaris populations from humans and pigs in China.

It has recently been shown using genetic markers that Ascaris in humans and pigs in Central America comprise reproductively isolated populations. We present a similar analysis for a region of China in which close association between pigs and humans has been the norm for thousands of years, and agricultural practices will result in frequent exposure to eggs from both sources. DNA fragments from selected regions of mitochondrial and ribosomal DNA were amplified by PCR and allelic forms identified following digestion with a panel of restriction enzymes, using DNA from a total of 115 individual worms from both people and pigs from 2 neighbouring villages. Significant frequency differences in both mtDNA haplotypes and the rDNA spacer were found between the 2 host-associated populations, indicating that they represented reproductively isolated populations. Mitochondrial haplotype frequencies were different from those observed in Guatemala and also from other Asian Ascaris populations, suggesting low levels of gene flow between populations. However, we found no evidence for significant heterogeneity in the genetic composition of Ascaris infrapopulations in either humans or pigs, possibly indicative of agricultural practices in China which have resulted in a random distribution of alleles within the parasite populations.

Eficacia antihelmintica del pamoato de oxantel-pirantel sobre ascaris lumbricoides, trichuris trichiura y anquilostomideos / Anthelmintic efficacy of oxantel pyrantel palmoate againts ascaris lumbricoides, trichuris trichiura and hookworms

Evaluar la eficacia antihelmíntica del Pamoato de Oxantel-Pirantel en 89 individuos de un sector marginal del Municipio Maracaibo, infestado por Ascaris lumbricoides, Trichuris trichiura y Anquilostomideos. Se analizó una muestra fecal de cada individuo mediante examen al fresco, concentración con formol-éter y recuento de huevos por la técnica de Stoll, antes y después y después del tratamiento. El antihelmíntico se administró a dosis única de 10 a 15 mg/kg-p. Se determinó la prevalencia y las asociaciones parasitarias. Se clasificó la población según intensidad de infestación y se evaluó la eficacia antihelmíntica a través de tasa de cura y prueba de reducción de huevos. T.trichiura fue el helminto más prevalente con un 74.2 por ciento de los casos, seguido por A.lumbricoides 62.9 por ciento y Alquilostomideos 20.2 por ciento. El poliparasitismo se presentó en el 51.7 por ciento y se demostró relación de afinidad entre A.lumbricoides y T.trichiura. La tasa de cura y la prueba de reducción de huevos para A.lumbricoides fue del 100 por ciento, para T.trichiura fue el 62.1 por ciento y 63.6 por ciento, y para Anquilostomideos fue del 61.1 por ciento y 38.2 por ciento. Pamoato de Oxantel-Pirantel mostró eficacia contra A.lumbricoides independiente del grado de infestación. Para T.trichiura y Anquilostomideos no se obtuvo una respuesta exitosa