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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.

This study aimed to compare three qualitative parasitological methods for the diagnosis of Syphacia muris infection in 30 Wistar rats (Rattus norvegicus) infected naturally. Methods of spontaneous sedimentation (Hoffman, Pons and Janer, or HPJ) and spontaneous flotation (Willis) for faecal samples and a method of taping (Graham) were performed and compared. The Graham and Willis methods were more sensitive than the HPJ method (P< 0.05). The Graham method was able to detect S. muris eggs in 100% of the samples. Eggs were detected in 83% and 60% of the samples using the Willis and HPJ methods, respectively. Method choice is important for screening for parasites of rats kept under laboratory conditions, as accurate diagnosis helps prevent future environmental contamination and infection. We concluded that the Graham method was the most efficient of those tested in this study for detection of S. muris infection in rats. This method is also rapid, inexpensive and practical, and should be implemented as a necessary measure for infection control.

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.

Our routine health-surveillance program is based on use of the Swiss Webster mouse, with sentinels submitted for testing every 7 weeks. Athymic nude (nu/nu) mice are used as an adjunct method to detect pinworm infections. The premise for the use of the nude mouse was based on research that revealed the thymus as necessary to confer resistance to pinworm infections. In light of this finding, it was inferred that an athymic mouse would be more susceptible to pinworm infections than a euthymic mouse, and hence a better sentinel animal for pinworm detection. To test the validity of this assumption, the Syphacia obvelata detection ability of the athymic nude mouse was compared to that of the Swiss Webster. Our results indicate no significant temporal difference in the detection ability of the two genotypes of mice. A clearance study for the parasite was also performed, in which the majority of Swiss Webster mice cleared the infection whereas athymic nude mice did not. In light of our results, we conclude that use of the athymic nude mouse for Syphacia obvelata detection offered no significant advantage over the euthymic Swiss Webster mouse for our program.

The authors describe a case of appendicular oxyuriasis and then go on to review the international literature on this condition. Nothing in the case report provides the surgeon with useful pointers which may help him distinguish between appendicular oxyuriasis and common appendicitis. This is in line with all the existing literature which yields no elements capable of suggesting an accurate preoperative diagnosis. Only anamnestic evidence of previous oxyuriasis can help the clinician in this direction. It should be noted, however, that there are no significant differences in postoperative morbidity between "common" acute appendicitis and appendicitis due to oxyuriasis, when the parasitosis is adequately treated.

Chronic pelvic inflammatory disease is a common gynecologic diagnosis in women with chronic pelvic pain. When standard antimicrobial therapy does not improve the clinical status, uncommon diagnoses such as Enterobius vermicularis should be considered. In this case, E vermicularis presented as acute and chronic salpingitis in a patient who had had E vermicularis-related appendicitis 5 years earlier.

The authors analysed 2849 patients who were admitted to the Department of General Surgery, Regional Hospital in Pisz in the years 1980-1989 with symptoms suggestive of appendicitis. In 983 cases surgical intervention was abandoned, because the symptoms regressed spontaneously or were caused by diseases of other organs. The pathological conditions associated with appendicitis are analysed in 1866 surgically treated patients. Cases of appendicitis caused by Oxyuris vermicularis, Salmonella-enteritidis and actinomycosis (one case each) and appendicular carcinoma (2 cases) are described in more detail. Attention is called to the aetiology, pathogenesis and treatment of these rare causes of appendicitis.

The prevalence of Enterobius vermicularis in four groups of adults, all trainee public health inspectors or public health nurses, aged 18-35 years and all living in hostels on campus was studied. The modified scotch tape technique was used and the subjects were taught to do the examination on themselves to detect the presence of eggs over a period of 6 successive mornings. Each was given an elaborately illustrated diagram on how and when to take the samples and given demonstration in groups. The samples were examined by trained people. Most of the subjects took samples on 6 consecutive days. Of the 119 subjects who returned samples, the overall prevalence of E. vermicularis was 9.2% and this was thought to be high for this particular age group. This was due to the higher prevalence (19.4%) in one group, whereas in the others the range was 3.5-8.0%. Based on the samples returned on the first day none of the subjects were detected as having the infection. After examination on 3 successive days (109 subjects) 10.1% were found to be infected (chi 2 = 10.704; d. f. = 1) and after examination on 6 successive days (72 subjects) 13.9% were found to be infected (chi 2 = 3.026; d. f. = 1). There was no significance between examination over 3 successive days and 6 consecutive days (chi 2 = 0.296; d. f. = 1). There was no difference in the prevalence between males and females.(ABSTRACT TRUNCATED AT 250 WORDS)

The pinworm, Enterobius vermicularis, is the most common intestinal parasite in the primary care setting, regardless of race, socioeconomic or cultural circumstances. This article discusses symptoms, diagnosis, and treatment.

A histologic examination was made of all appendices delivered to the Dept. of Pathology, Sundby Hospital, Copenhagen, in 1980-87, to ascertain the incidence of Enterobius vermicularis (pinworm) and the possible relation to acute appendicitis. Altogether 2267 appendices were examined, and E. vermicularis was identified in 4.1%. The highest incidence occurred in the 6- to 15-year age group. Infestation was more frequent in female than in male appendices, with the ratio of 1 male to 1.8 females, except in the 11- to 15-year age group, in which the ratio was 1. There was a highly significant difference in the incidence of E. vermicularis in normal appendices and in inflamed appendices, which may indicate that 1) the presence of E. vermicularis in the appendix can give the symptoms of acute appendicitis, or 2) E. vermicularis leaves or does not enter an inflamed appendix.

In order to determine how many consecutive perianal examinations can increase the accuracy of the diagnosis of enterobiasis, nursery and kindergarten children were examined with 8 consecutive scotch-tape perianal swabs. Primary school students were examined with 4 consecutive swabs, while junior high school students were examined with one swab in the morning and another in the afternoon. The positive rates among nursery and kindergarten children increased from 17.3% and 34.6% by a single swab to 44.4% and 70.2% by 8 consecutive swabs respectively. Significant differences in rates among kindergarten children by class were found by 4 to 8 swabs (3rd year class 65.6-78.7%, 2nd year class 50.3-61.1%, 1st year class 52.3-69.5%). The rate among primary school students increased from 59.9% by a swab to 77.3% by 4 consecutive swabs. Significant differences were found among the rates by grade. The highest was detected in grade 3 and lowest in grade 6. There was no significant difference between the positive rates among junior high school students obtained in the morning (33.7%) and in the afternoon (31.3%), and also no significant difference among rates by junior school was found. There was no significant difference between positive rates by sex in kindergarten children (boys, 68.8%, girls, 71.9%) and primary school students (boys, 76.8%; girls, 77.9%). However, the positive rate of junior high school girls (47.3%) was significantly higher than that of junior high school boys (37.4%).(ABSTRACT TRUNCATED AT 250 WORDS)

Oxyuriasis is one of the commonest infestations in our area, with rates ranging from 5% to 75% in several studies. The present study was carried out in 100% of schoolchildren in a rural town with a population of 1,000 in the Lerida province. The study had two parts. On the one side, the prevalence of oxyuriasis was evaluated with Graham's test; on the other side, a self administered questionnaire was distributed to assess the validity of the surveyed symptoms for the diagnosis of oxyuriasis. The results disclosed a 59.5% prevalence, which was somewhat higher in girls than in boys. The study of diagnostic validity showed that the only symptom with a high yield was the anal and/or genital pruritus. The remaining symptoms could be discarded due to their low reliability.

In this study; the parasite prevalence of schools with different socio-economical status and three methods for diagnosing intestinal parasitosis were evaluated. Children from two primary schools and one junior high school with different socio-economical status participated in the study. The three method used for diagnosing parasitosis in this study were direct wet mounts, concentrated saline flotation technique, and zinc sulfate centrifugal flotation method. Parasitosis was found in 69 fecal samples (18%). The distribution of the parasites found were Hymenolepis nana (29%), Ascaris lumbricoides (26%), Enterobius vermicularis (23%), Trichirus trichiura (18%), taenia saginata (4%). The parasite prevalence in schools with low and high socioeconomical status differed significantly (27% vs. 5% respectively). Combined methods were superior to single methods. The combined method of direct wet mounts and zinc sulfate centrifugal flotation was the most sensitive method (diagnosis rate 90%). But we think that the combined method of direct wet mounts and concentrated saline flotation technique is a simpler method with almost equal results (86%).

The pinworm prevalence among 302 children tested in 1980 in five Southern California elementary schools was determined to be 11.6%. The range was 7.3-15.4%. In a 1982 study involving 158 children in six schools, the prevalence was 21.6% (range 11.1-38.9%). The results of these studies are compared with those of a similar prevalence study done in the same area and in some of the same schools during the 5-year period 1960-1964. The prevalence for the earlier period, involving 700 children in six schools, was 34.6%, and ranged from 29.2-43.0%. A new, flexible, plastic pinworm slide was used in the 1980 and the 1982 studies. In the 1982 study, this diagnostic method was evaluated and compared for efficiency and use against the standard cellulose tape/glass slide. The two are equally effective in picking up eggs, and in reading quality. The plastic slide is easier to use and does not break.

A fairly high number of symptoms are usually ascribed to intestinal parasites, a fact leading many times to various treatments in the absence of diagnostic evidence. Aiming to correlate presence of parasite with that of signs and symptoms authors have reviewed 1,131 patients submitted, for several reasons, to a search of parasites which was positive in only 384 cases. Authors conclude that only eosinophilia is a quite constant finding in E. vermicularis infestation and abdominal pain and chronic diarrhea are often present during giardia infestations.

General descriptions and monographs of the five parasites most likely to be seen in U. S. patients are presented. The appended monographs are designed to be a starting reference for answering drug information questions regarding these parasites. The drugs covered in the monographs are listed in the order of suggested use.

Controversy surrounds studies of the incidence and clinical importance of atopic disease in tropical populations. This could be due in part to the methods of evaluation employed. The value of some of the tests commonly used in the diagnosis of atopic disease was therefore examined in a tropical situation. Extracts of environmental allergens are usually obtained from suppliers located in more temperate regions of the world, and skin tests, the radio-allergosorbant test (RAST) and RAST-inhibition demonstrate that these can lack important tropical allergens. In addition, although some local extracts are used in clinical practice, these have great variability in their protein content, allergenicity and toxicity. In the tropical environment serum IgE levels can have a greater relation to intestinal helminthic infestation than to atopic disease, even after anti-parasitic treatment, and thus the definition of "normal" IgE values must take into account the socio-economic status of the groups examined. The helminth-induced elevation of total serum IgE levels can also cause false-positive RAST results.

Four cases of Enterobius vermicularis infection and one case of Strongyloides stercoralis infection were found during the examination of 22,700 routine Papanicolaou-stained cervicovaginal smears and 434 urinary sediments. Ova of E. vermicularis were observed in the urocytograms from three girls and in the vaginal smear of a young woman. In a second woman, a S. stercoralis larva was detected in the routine vaginal smear. A clear background or a mild inflammatory pattern was noted in the smears in these cases.