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The role of rodents as reservoirs of helminths of public health importance is not well known. The zoonotic potential of Syphacia spp. has been confirmed; therefore, the study aimed to estimate the occurrence of oxyurid nematodes in small rodents from pet shops and breeding clubs in Slovakia. Fecal samples of 586 pet rodents kept in 133 cages were collected between 2016 and 2018 and examined by Faust´s flotation method. Four species of oxyurid nematodes, Syphacia muris, S. obvelata, Aspiculuris tetraptera and Paraspidodera uncinata were detected. A. tetraptera was found in the faecal samples of all rodent species included in this survey. The number of positive boxes varied from 5.4% in hamsters to 70.0% with mice. The prevalence of Syphacia muris was highest in Mongolian gerbils where up to 75.0% boxes were positive; S. obvelata was found in 26.7% of boxes with mice, 25.0% of boxes with Mongolian gerbils and 3.2% of boxes with rats. The high prevalence of Syphacia spp. in all animal species points out the infection risk for humans. Animals offered for sale are often in close contact with human beings; therefore they should be regularly tested for parasites and then effectively dewormed.

The popularity of Mongolian gerbils (Meriones unguiculatus) as pets as well as experimental animals is continuously increasing. Mongolian gerbils are the main natural hosts of the nematode Dentostomella translucida, also referred to as pinworm, threadworm, or seatworm. D. translucida (Oxyuridae) was recently detected in the necropsy of a gerbil housed at the experimental animal production center of Adnan Menderes University Faculty of Veterinary Medicine. Mongolian gerbils are the main natural hosts of D. translucida, also referred to as pinworm. During necropsy in this animal, 26 parasites were collected from the small intestine and microscopically examined. The length of the female and male parasites was determined as 15.6-25.4 (mean, 18.3) and 10.2-16.8 (mean, 13.3) mm, respectively. The mean esophageal length in the female and male parasites was 397.3 and 325.3 mµ, respectively. The vulva of the females was close to the front end and was approximately 8.7 mm in length. The males had a single spiculum of approximately 342 mµ in length. There were seven papillae around the cloaca. During postmortem examination, eggs were also detected in feces collected from the gerbil's rectum. The eggs were spindle-shaped, slightly asymmetric, and had a diameter of 117-128 × 45-49 mµ (mean, 120 × 48 mµ). D. translucida, which is a parasite specific to gerbils, may easily affect other members of the animal colony. Thus, controling its presence in gerbil breeding units is essential.

Sentinel exposure to soiled bedding is frequently used for health monitoring of mice housed in individually ventilated cage systems (IVCS). Despite its advantages, the use of soiled bedding sentinels (SBSs) is far for being a reliable method. Two studies were conducted to evaluate the sensitivity of immunodeficient SBSs NOD.CB17-Prkdc(scid)/NCrHsd (NOD SCID) against two immunocompetent outbred strains, Hsd:ICR (CD-1) and RjOr1:Swiss (Swiss) to pinworm detection in IVCS-housing. Four different diagnostic methods were used: perianal tape test, fecal flotation, plate method and histology. Positivity was considered if at least one of the techniques used was positive. In the first study NOD SCID were more sensitive than CD-1 SBSs (P < 0.05), and except for the fecal flotation test performed at week 6, all the diagnostic methods were more sensitive with NOD SCID mice (P < 0.05). In the second study differences between the Swiss and NOD SCID mice were less obvious (P = 0.08). When compared separately, the different diagnostic methods, except for the fecal flotation test, were all more sensitive in the NOD SCID mice (P < 0.05). In addition, the anal tape test in the Swiss SBSs was more sensitive at week 7 than at week 15 (P < 0.05). In conclusion, combining various diagnostic techniques and samplings at week 7 post-exposure with non-invasive methods increases the rate of pinworm detection. Immunodeficient SBSs showed higher sensitivity than immunocompetent ones. Thus, use of immunodeficient SBSs is highly recommended in health control protocols., (© The Author(s) 2015.)

Rodent pinworms persist in many institutions, suggesting deficiencies in eradication and diagnostic processes. When pinworms are detected, treatment success is common, but false-negative test results during health surveillance or after treatment likely contribute to the continued presence of this parasite. PCR testing is not always practical, and increased information regarding the life cycle and general epidemiology of pinworm infestations could improve the sensitivity of traditional nonPCR detection methods and improve eradication efforts. We therefore investigated a pinworm (Syphacia muris) infestation in Sprague-Dawley rats (Rattus norvegicus) to develop a more accurate testing strategy. In addition, we sought to determine the duration of egg viability by using an in vitro hatching protocol to assess environmental persistence. Finally, we tested the ovicidal efficacy of a disinfectant used at our institution. Eggs were shed in higher numbers in the midafternoon as compared with other times of the day, and the sex of the host had no consistent effect on egg shedding. Egg shedding showed periodicity over time, with shedding decreasing to 0 at 2- to 3-wk intervals. Neither cecal examination nor tape tests alone reliably predicted pinworm infestation, and results of the 2 tests did not necessarily coincide. Eggs aged for as long as 7 mo remained viable, indicating a potential for recontamination from the environment. Finally, gaseous chlorine dioxide was an effective ovicidal agent, with a kill rate of 99.7%. These results suggest that strategies for S. muris eradication can be optimized to increase detection and elimination.

Mites of 3 genera-Myobia, Myocoptes, and Radfordia -continue to plague laboratory mouse facilities, even with use of stringent biosecurity measures. Mites often spread before diagnosis, predominantly because of detection difficulty. Current detection methods have suboptimal sensitivity, are time-consuming, and are costly. A sensitive serodiagnostic technique would facilitate detection and ease workload. We evaluated whether total IgE increases could serve as a serodiagnostic marker to identify mite infestations. Variables affecting total IgE levels including infestation duration, sex, age, mite species, soiled-bedding exposure, and ivermectin treatment were investigated in Swiss Webster mice. Strain- and pinworm-associated effects were examined by using C57BL/6 mice and Swiss Webster mice dually infested with Syphacia obvelata and Aspiculuris tetraptera, respectively. Mite infestations led to significant increases in IgE levels within 2 to 4 wk. Total IgE threshold levels and corresponding sensitivity and specificity values were determined along the continuum of a receiver-operating characteristic curve. A threshold of 81 ng/mL was chosen for Swiss Webster mice; values above this point should trigger screening by a secondary, more specific method. Sex-associated differences were not significant. Age, strain, and infecting parasite caused variability in IgE responses. Mice exposed to soiled bedding showed a delayed yet significant increase in total IgE. Treatment with ivermectin reduced total IgE levels within 2 wk. Our data suggest that increases in total IgE in Swiss Webster and C57BL/6 mice warrant investigation, especially because mite infestations can rapidly elevate total IgE levels. We propose that using total IgE levels routinely in serologic panels will enhance biosecurity.

The present investigation examined the prevalence and intensity of pinworm infection in laboratory mice from three laboratory animal centres in China's southern Guangdong Province between August 2008 and April 2009. A total of 301 laboratory mice representing BALB/c, Kunming (KM) and C57BL/6J breeds were examined and the worms were counted and identified according to existing keys and descriptions, and their specific identity was ascertained by polymerase chain reaction (PCR) amplification of the second internal transcribed spacer (ITS-2) of ribosomal DNA. While the BALB/c and C57BL/6J mice were not found to be infected with pinworms, postmortem examination of the KM mice revealed a prevalence of 46.7%. PCR amplification of ITS-2 rDNA and subsequent sequencing confirmed that the mice were infected with Syphacia obvelata. The results of the present investigation demonstrated that the prevalence of pinworm infection in laboratory mice was high in the Guangdong province, and integrated control strategies and measures should be implemented to prevent and control pinworm infection in laboratory mice.

Enterobius vermicularis (the pinworm) commonly infests the lumen of the intestine but on rare occasions has been found in the wall or in the tissues outside the gastrointestinal tract. Three such patients have been encountered in whom Enterobius vermicularis was found in the wall of the colon, in the retrocaecal tissues, and on the peritoneum. The pathological lesions and their relationship to the clinical features are discussed. A brief review of the literature is given. It is concluded that Enterobius vermicularis can only penetrate the wall of the gastrointestinal tract if this is diseased. Once in the tissues the worms can cause an inflammatory reaction simulating carcinoma and Crohn's disease, and, by perforation of the intestine, cause a generalized peritonitis.