Evaluation of the MGL method to detect Paragonimus eggs and its improvement

Copro-prevalence of Fasciola hepatica in Chilean breed horses in the province of Concepción, Chile

The aim of this research was to assess the copro-prevalence of Fasciola hepatica in owned Chilean breed horses (Equus caballus) residing in the province of Concepción, Chile. The study was carried out throughout October 2017. Samples were taken from all (100%) Chilean breed horse (124 specimens; 45 females and 79 males, aged between 7 months and 24 years old) from the Concepción province. A rectal stool sample was obtained from each animal. This was analyzed using the Army Medical School method (AMS III) technique to detect F. hepatica eggs. Information about the horse's age, sex, previous fasciolicide application, and an assessment of body condition was also obtained. Fisher tests were carried out to analyze the results. Ten horses (8.06%) were positive for the presence of F. hepatica eggs. No significant difference of copro-prevalence was found between age (young 8.47%, old 7.69%), sex (female 11.1%, male 6.33%), the previous application of fasciolicide (dewormed 10%, not dewormed 7.89%), or body condition (low condition 11.1%, high condition 0.7%) categories (Fisher tests: P>0.05 in all cases). The results of this study suggest that Chilean breed horses constitute part of the reservoir of F. hepatica for both ruminant populations and humans in the Concepción province.

An advanced protocol for the purification of whipworm eggs from feces for use as therapeutic agents

Recent studies have attempted to treat autoimmune diseases using Trichuris suis. whipworm) eggs. Large quantities of eggs can be obtained efficiently by collecting from the feces of the porcine hosts rather than by extracting from the female worm uterus. However, it is difficult to process large amounts of feces using the current methods. In the present study, we propose a method to collect the eggs from bulk feces more efficiently. Collecting the eggs using washing meshes (25 μm sieve) yields 65.7% (56.0-70.7) of eggs (median, min-max) from 100 g feces. Our method, which uses ethyl acetate and simulated gastric fluid, yielded 91.4% (91.4-94.0) of the eggs from 100 g feces into the separated aqueous solution. Egg collection using simulated gastric fluid (SGF) method was also 60 min faster than that using the sieve method. As the SGF used in the experiment is a strongly acidic reagent with a pH of 1-2, embryonation of the eggs was induced by the rapid pH change. As a result, 37.1% (8.0-77.8) of the eggs had embryonated two months after SGF stimulation. Using the developed method, we could process the feces quickly and efficiently. Furthermore, after purification, egg embryonation could be induced without any harmful reagent treatment. This method is expected to be helpful for further research using Trichuris suis eggs.

Infection with Paragonimus westermani of boar-hunting dogs in Western Japan maintained via artificial feeding with wild boar meat by hunters

Infection of boar-hunting dogs with Paragonimus westermani was investigated in Western Japan. Blood and rectal feces were collected from 441 dogs in the three districts (205 in Kinki, 131 in Chugoku and 105 in Shikoku District). In a screening ELISA for serum antibody against P. westermani antigen, 195 dogs (44.2%) showed positive reaction. In the 195 dogs, 8 dogs were found excreting P. westermani eggs after molecular analysis of fecal eggs, and additional 7 were identified serologically for the parasite infection because of their stronger reactivity against P. westermani antigen than against antigens of other species of Paragonimus. A spatial analysis showed that all of the P. westermani infections were found in Kinki and Chugoku Districts. In this area, dogs’ experience of being fed with raw boar meat showed high odds ratio (3.35) to the sero-positivity in the screening ELISA, and the frequency of such experiences was significantly higher in sero-positive dogs. While clear relationship was not obtained between predation of boars by dogs during hunting and their sero-positivity. Therefore, it is suggested that human activity of feeding with wild boar meat is the risk factor for P. westermani infection in boar-hunting dogs. Considering that hunting dogs could play as a major definitive host and maintain the present distribution of P. westermani in Western Japan, control measures for the infection in hunting dogs, such as prohibition of raw meat feeding and regular deworming, should be undertaken.