[Prevalence of Enterobius vermicularis infections among children in China from 2016 to 2021: a meta-analysis].

OBJECTIVE: To investigate the prevalence of Enterobius vermicularis infections among children in China from 2016 to 2021, so as to provide insights into enterobiasis control and formulation of the enterobiasis control strategy among children. METHODS: Publications pertaining to the prevalence of E. vermicularis infections among children were retrieved from Wanfang Data, CNKI, VIP and PubMed databases published from January 2016 to June 2023. Eligible publications were screened according to inclusion and exclusion criteria, and the publication bias was evaluated using the assessment tool for prevalence studies proposed by the Joanna Briggs Institute Evidence-Based Practice Resources in Australia. The study period, study areas, study subjects, sample size and number of infections were extracted from publications, and a pooled analysis was performed using a meta-analysis. A meta-regression analysis was performed with the prevalence of E. vermicularis infections as an independent variable, and sample size, source of samples, study area, study method, geographical area and province as dependent variables to identify the source of the study heterogeneity. RESULTS: A total of 66 studies were included, covering 23 provinces (municipalities, autonomous regions) in China, and with the investigations conducted between 2016 and 2021. Meta-analysis showed that the pooled prevalence of E. vermicularis infections was 4.5% [95% confidence interval (CI): (3.1%, 6.0%)] among children in China from 2016 to 2021, and the annual prevalence was 4.1% [95% CI: (2.2%, 6.5%)], 4.2% [95% CI: (2.4%, 6.6%)], 4.2% [95% CI: (2.2%, 6.8%)], 3.2% [95% CI: (1.5%, 5.4%)], 2.3% [95% CI: (0.9%, 4.3%)] and 1.1% [95% CI: (0.4%, 2.1%)] from 2016 to 2021. The pooled prevalence of E. vermicularis infections was 4.9% [95% CI: (3.4%, 6.8%)] in studies with a sample size of < 5 000 cases, which was higher than that in studies with a sample size of 5 000 cases and higher [2.1%, 95% CI: (0.2%, 3.6%)], and the pooled prevalence of E. vermicularis infections was 5.2% [95% CI: (2.9%, 8.2%)] among subjects from schools, which was higher than that among subjects from communities [4.2%, 95% CI: (2.7%, 6.0%)]. The pooled prevalence of E. vermicularis infections was 4.4% [95% CI: (2.8%, 6.2%)] among children included in comprehensive surveillance, which was higher than that among children included in specific surveillance [4.8%, 95% CI: (2.6%, 7.7%)], and the pooled prevalence of E. vermicularis infections was 5.7% [95% CI: (3.8%, 7.8%)] among children included in county-level surveys, which was higher than that among children included in city-[4.8%, 95% CI: (2.3%, 8.0%)] and province-level surveys [1.8%, 95% CI: (0.3%, 4.7%)]. In addition, the pooled prevalence of E. vermicularis infections was higher among children in southern China [11.3%, 95% CI: (7.5%, 15.7%)] than that in central China [5.2%, 95% CI: (2.8%, 8.2%)], eastern China [5.2%, 95% CI: (2.8%, 8.2%)] and southwestern China [2.6%, 95% CI: (1.4%, 4.1%)]. Meta-regression analysis identified geographical area and survey province as factors affecting the study heterogeneity. CONCLUSIONS: Currently, the overall prevalence of E. vermicularis infections is moderate among children in China, and the prevalence varies greatly in regions, with a high prevalence rate in southern China and presence of small-scale clusters. Enterobiasis surveillance and health education pertaining to enterobiasis control are required with adaptations to local circumstance to reduce the prevalence of E. vermicularis infections among children.

Changes in Light Energy Utilization in Photosystem II and Reactive Oxygen Species Generation in Potato Leaves by the Pinworm Tuta absoluta.

We evaluated photosystem II (PSII) functionality in potato plants (Solanum tuberosum L.) before and after a 15 min feeding by the leaf miner Tuta absoluta using chlorophyll a fluorescence imaging analysis combined with reactive oxygen species (ROS) detection. Fifteen minutes after feeding, we observed at the feeding zone and at the whole leaf a decrease in the effective quantum yield of photosystem II (PSII) photochemistry (ΦPSII). While at the feeding zone the quantum yield of regulated non-photochemical energy loss in PSII (ΦNPQ) did not change, at the whole leaf level there was a significant increase. As a result, at the feeding zone a significant increase in the quantum yield of non-regulated energy loss in PSII (ΦNO) occurred, but there was no change at the whole leaf level compared to that before feeding, indicating no change in singlet oxygen (1O2) formation. The decreased ΦPSII after feeding was due to a decreased fraction of open reaction centers (qp), since the efficiency of open PSII reaction centers to utilize the light energy (Fv'/Fm') did not differ before and after feeding. The decreased fraction of open reaction centers resulted in increased excess excitation energy (EXC) at the feeding zone and at the whole leaf level, while hydrogen peroxide (H2O2) production was detected only at the feeding zone. Although the whole leaf PSII efficiency decreased compared to that before feeding, the maximum efficiency of PSII photochemistry (Fv/Fm), and the efficiency of the water-splitting complex on the donor side of PSII (Fv/Fo), did not differ to that before feeding, thus they cannot be considered as sensitive parameters to monitor biotic stress effects. Chlorophyll fluorescence imaging analysis proved to be a good indicator to monitor even short-term impacts of insect herbivory on photosynthetic function, and among the studied parameters, the reduction status of the plastoquinone pool (qp) was the most sensitive and suitable indicator to probe photosynthetic function under biotic stress.

Effects of anthelmintics on the pinworm Blatticola blattae in laboratory-reared German cockroaches Blattella germanica.

The efficacy of pyrantel pamoate, pyrvinium pamoate, ivermectin, and piperazine citrate against pinworm in cockroach was evaluated. Laboratory-reared German cockroaches naturally infected with Blatticola blattae were treated with the anthelmintics and necropsied at 3 to 35 days after treatment. Ivermectin at over 5 ppm and piperazine citrate at over 2000 ppm killed all the treated cockroaches. Pinworms were still detected in cockroaches given lower concentration of the aforementioned drugs. Administration of pyrantel pamoate (100-1000 ppm) and pyrvinium pamoate (2000 ppm) did not kill the cockroaches, and no pinworms were detected at 3 and 17 days after treatment. Thus, pyrantel pamoate and pyrvinium pamoate were found to be effective for deworming B. blattae in the German cockroaches, without causing mortality for the host. Our results showed that anthelmintics selection is essential for eradication of pinworms in cockroaches because of the toxicity for the host such as ivermectin or piperazine citrate. This is the first report of piperazine citrate toxicity in cockroaches.

[National surveillance on Enterobius vermicularis infections among children at ages of 3 to 9 years in China from 2016 to 2018].

OBJECTIVE: To understand the epidemic status of Enterobius vermicularis infections among children aged 3 to 9 years in China, so as to provide scientific basis for the formulation of the prevention and control strategies for enterobiasis. METHODS: The national surveillance of enterobiasis was performed in 736 national surveillance sites (counties) from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018. All surveillance sites were classified into parts according to the geographical directions, including the eastern, western, southern, northern and middle parts, and a township was randomly selected from each part. Then, an administrative village was randomly selected from the township, and 200 permanent residents at ages of over 3 years living in the administrative village were randomly selected using the cluster sampling method. A total of 1 000 residents were examined in each surveillance site. E. vermicularis infections were detected among children at ages of 3 to 9 years using the modified Kato-Katz technique and the adhesive cellophane-tape perianal swab method, and the prevalence of infections was calculated and compared. RESULTS: The prevalence of E. vermicularis infections was 2.50%, 2.84% and 2.46% among children at ages of 3 to 9 years in the 736 surveillance sites from 30 provinces (municipalities/autonomous regions) in China from 2016 to 2018, and there was no gender-specific prevalence of E. vermicularis infections (P > 0.05). Enterobiasis was main prevalent in the southern and southwestern part of China (Jiangxi, Guangxi, Guangdong, Sichuan, Fujian, Chongqing and Hainan), with 5.00% prevalence and greater, and the highest prevalence was seen in Jiangxi and Guangxi for successive 3 years. In addition, the prevalence of E. vermicularis infections was higher in children with the Han ethnicity than in those with the minority ethnicity, and a high prevalence was found in children at ages of 4 to 7 years, and a low prevalence seen in children at ages of 3, 8 and 9 years. CONCLUSIONS: The prevalences of E. vermicularis infections have not changed much among children at ages of 3 to 9 years in China from 2016 to 2018, and high prevalence is seen in southern and southwestern China, which should be given a high priority.

Unusual Etiology for Transaminitis.

An infection with Enterobius vermicularis (pinworm) commonly affects the gastrointestinal (GI) tract. The ectopic localization of an enterobius infectious is rare, especially in the liver. We report the case of a 37-year-old man who presented to the gastroenterology clinic with abdominal pain and was found to have elevated transaminases. Workup for acute/chronic liver disease was unrevealing. He underwent endoscopic evaluation showing a live pinworm in the colon. He was treated with albendazole with improvement in GI symptoms and resolution of his transaminitis. There are scarce reports in the literature describing pathognomonic, clinical, imaging, and laboratory findings for pinworm infection. Here, we attempt to review the literature for hepatic involvement with an enterobius infection and discuss the findings via this case.

Inadvertent detection of massive Enterobius vermicularis infection in an asymptomatic adult with rectal blowout following barotrauma

Enterobius vermicularis (pin worm) is a common intestinal parasite infection which usually affects children and rarely causes significant illness. However, of the few reports of extra-intestinal E. vermicularis infection reported in the literature, patients can have significant morbidity and mortality, thus stressing the need for appropriate management of pin worm infection. We report a case of massive E. vermicularis infection in a 20-year-old male which was inadvertently discovered during an emergency abdominal surgery. The case emphasizes the need to perform routine ova-parasite screening at periodic intervals to detect intestinal parasitic infections, to promote adequate practices to improve sanitation facilities and to direct appropriate therapeutic measures to eliminate the worm burden in case of infections.

Polyparasitism of Rhabditis Axei and Enterobius Vermicularis in a Child from Beijing, China.

BACKGROUND: Rhabditis (Rhabditellae) axei is a common species in soil, which has been reported repeatedly in human urine and the digestive system. Humans exposed to sewage or mistakenly polluted sewage is the cause of larvae infecting the digestive tract or via the urethra. We reported a patient infected with Rhabditis axei and Enterobius Vermicularis. The migration of the nematodes caused true signs of hematuria, diarrhea, and high eosinophilia. METHODS: Stool and urine are collected to detect parasite eggs and genotype. Specimens are sent for polymerase chain reaction (PCR)-based species identification. Amplification of the 18S ribosomal RNA gene was performed by PCR as described [1]. RESULTS: Morphological features and PCR amplification of the 18S ribosomal RNA gene confirmed Rhabditis axei and Enterobius vermicularis as the pathogen of infection. CONCLUSIONS: Herein, we presented a case that confirmed Rhabditis axei and Enterobius vermicularis infection in humans can be associated with high eosinophilia.

Distribution and reproductive plasticity of Gyrinicola batrachiensis (Oxyuroidea: Pharyngodonidae) in tadpoles of five anuran species.

Previous studies on Gyrinicola batrachiensis indicate that these pinworms have distinct reproductive strategies dependent on the development time to metamorphosis of their anuran tadpole hosts. In tadpoles of amphibian species with short developmental periods (a few weeks), female nematodes reproduce parthenogenetically, and only produce thick-shelled eggs used as transmission agents from tadpole to tadpole. In contrast, nematodes in tadpoles with longer larval developmental periods (months to years) reproduce by haplodiploidy, and females produce thick-shelled as well as autoinfective thin-shelled eggs. However, recent investigations on the haplodiploidy strain of G. batrachiensis indicate that plasticity exists in the ability of these nematodes to produce thin-shelled autoinfective eggs when these nematodes infect tadpoles of co-occurring amphibian species. Yet, little information is available on the potential mechanism for this reproductive plasticity because few co-occurring amphibian species have been examined for the reproductive strategies of these nematodes. Therefore, our goals were to document field host specificity and reproductive strategies of nematode populations in tadpoles of five co-occurring amphibian species that varied in their larval developmental periods. Additionally, we evaluated adult worm morphology from each infected amphibian species to assess any differences in worm development and reproductive strategy of pinworm populations in different amphibian species. Of the five amphibian species examined, four were infected with the haplodiploid strain of G. batrachiensis. Prevalence of G. batrachiensis ranged from a high of 83% in Acris blandchardi to a low of 15% in Pseudacris clarkii; whereas mean intensity was highest for Rana sphenocephala (10 ± 10.36) and lowest for Hyla chrysoscelis (3.23 ± 3.35). Prevalence appeared to be controlled by tadpole ecology and life history, while mean intensity appeared to be controlled by tadpole physiology and worm reproductive strategy, but not necessarily the developmental period of each anuran species. G. batrachiensis observed in long developing tadpoles of R. sphenocephala had high mean intensities and conformed to the haplodiploidy reproductive strategy with both male and female worms being present, and females produced thick-shelled and thin-shelled eggs. In contrast, tadpoles of A. blanchardi, H. chrysoscelis, and P. clarkii, which varied in their developmental times from long to short, had relatively low mean intensities and contained both male and female G. batrachiensis. However, female worms only produced thick-shelled eggs in these hosts. Importantly, morphological differences existed among female worms recovered from R. sphenocephala and female worms recovered from A. blanchardi tadpoles with long developmental periods. These data strongly suggest that when the haplodiploidy strain of G. batrachiensis is shared by tadpoles of different amphibian species, species-specific differences in interactions between these nematodes and their development in different amphibian host species have a strong influence on the reproductive plasticity of these nematodes.

Acute suppurative appendicitis associated with Enterobius vermicularis: an incidental finding or a causative agent? A case report.

BACKGROUND: Histological acute appendicitis patterns associated with Enterobius vermicularis is an extremely rare finding. The exact role of this parasite in acute appendicitis is controversial as usually resected specimens show no evidence of histological inflammation. CASE PRESENTATION: We present herein a case of a 21-year-old male Arabic patient who presented with clinical syndrome of acute appendicitis. Emergency appendectomy was performed and the histopathological examination of the resected specimen showed the presence of E. vermicularis as well as intense acute inflammatory patterns such as mucosal ulceration and suppurative necrosis. The post-operative course was uneventful and the patient was discharged with appropriate anti-helmintic drug prescription. CONCLUSION: Acute appendicitis due to E. vermicularis is a very rare occurrence. The histopathological analysis of resected specimens should pay special attention to search for this parasite for adequate post-operative treatment of patients.

[Effect of control program of human intestinal parasitic diseases in Nanping City].

OBJECTIVE: To understand the epidemic status of human intestinal parasitic diseases and evaluate the effect of the control program in Nanping City, so as to provide an evidence for improving the disease control. METHODS: The villages were selected by the stratified cluster sampling method and the residents in these villages were surveyed for human intestinal parasitic diseases, and kindergartens were also selected and the children in these kindergartens were surveyed for Enterobius vermicularis infection. RESULTS: In 2007, before the control program, 9 851 residents of Nanping City were surveyed, with the parasitic infection rate of 9.10% (896 infection cases), and the infection rate of E. vermicularis of children was 18.56% (328/1 767). From 2011 to 2014, when the control program was performed, 4 679 residents were surveyed, with the infection rate of 4.06% (190 infection cases), and the infection rate of E. vermicularis of children was 3.87% (33/853). After the control program was launched, the infection rates of human intestinal parasites were decreased. The overall parasitic infection rate and hookworm infection rate showed increasing trends by age (χ2 = 49.03 and 53.58 respectively, both P < 0.01). CONCLUSIONS: The infection situation of human intestinal parasites is decreased after the implementation of the control program but the infection rate is still at a high level, and the control work should be strengthened.

Negligible Egg Positive Rate of Enterobius vermicularis and No Detection of Head Lice among Orphanage Children in Busan and Ulsan, Korea (2014).

To determine whether pinworm infections and head lice infestations spread among children in orphanages, 117 children from 4 orphanages in Busan-si and Ulsan-si, Korea, were examined for enterobiasis and head lice infestation between January and February 2014. The overall rate of Enterobius vermicularis egg positivity was 0.85%, whereas none of the children had head lice infestations. The rate of pinworm infection was much lower among the orphanage children compared to the rates observed in previous studies among kindergarten and primary school students. Moreover, the risk factors for enterobiasis were less frequent among these subjects than previously reported. The personal hygiene and health of the orphanage children were supervised by a regular, employed nurse through a health education program. In conclusion, pinworm infection was efficiently controlled among the children in orphanages, and this might be related to good personal hygiene practices in Korea.

[Prevalence and risk factors of Enterobius vermicularis among preschool children in kindergartens in Luohu District, Shenzhen City].

OBJECTIVE: To understand the prevalence and risk factors of Enterobius vermicularis among preschool children in kindergartens in Luohu District, Shenzhen City. METHODS: A total of 489 children in 6 kindergartens were selected by the stratified sampling method and investigated for E. vermicularis infection by the cellophane anal swab technique. The information of sanitary condition of the kindergartens, personal hygiene, and family hygiene were investigated by questionnaire. RESULTS: The infection rate of E. vermicularis was 10.2% (50/489). The single factor analysis indicated that the following factors might related to the infection: the different classes of kindergartens, grades, ground of bed ioom, private toilet, types of taps and beds, bed management, education levels of parents, frequency of shower and washing anus, and washing hands before meal and after WC. The multivariate Logistic analysis indicated that the bed management, education level of mothers, frequency of washing anus, and private toilet were independent risk factors for E. vermicularis infection. CONCLUSION: To control the infection of E. vermicularis, the circumstance and management of kindergartens, parents' knowledge of E. vernicularis infection, and children's healthy habit need improve.

Risk Factors and Relationship Between Intestinal Parasites and the Growth Retardation and Psychomotor Development Delays of Children in Sanliurfa, Turkey.

OBJECTIVE: The objective of this study was to determine the risk factors for and relationship among parasitic infections, growth retardation, and psychomotor developmental delays in children aged 6 years and below. METHODS: This case-control study was performed in Sanliurfa in southeastern Turkey between October and December 2007. Data were collected using a structured questionnaire, anthropometry, Ankara Development Screening Inventory, and laboratory analysis of stool specimens. RESULTS: The most common parasite was Giardia intestinalis (42.53%) followed by Enterobius vermicularis (27.58%), Ascaris lumbricoides (18.39%), Hymenolepis nana (5.75%), Trichuris trichiura (3.45%), Escherichia coli (1.15%), and Blastocystis spp. (1.15%). Fifty-eight percent of all children were infected with intestinal parasites; 55.2% had only one parasite, whereas 44.8% had multiple parasites. The children infected with G. intestinalis and other intestinal parasites had significantly higher levels of growth retardation and psychomotor development delay than non-infected children. Children with parasitic infections had growth delay up to 2.9 times, general development delay up to 1.9 times, language-cognitive development delay up to 2.2 times, and fine motor development delay up to 2.9 times higher than children without any parasitic infections. However, no significant relationship among intestinal parasites, gross motor development, social-self skills, and development delay was identified. The education level of parents, poor economic situation, number of households, not washing hands, playing with soil, family history of parasitic infection were the significant risk factors for intestinal parasites. CONCLUSION: Our study indicates that the presence of either malnutrition or intestinal parasites may put a child in a high-risk group for developmental delays and growth retardation. Therefore, public health interventions can embrace nationwide deworming in children.

[Monitoring of Enterobius vermicularis infection among children from 2006 to 2010 and SWOT analysis].

OBJECTIVE: To understand the infection status and variation tendeNcy of Enterobius vermicularis infection among children at national monitoring spots of soil-transmitted nematodosis from 2006 to 2010, and master the epidemic regularity, so as to provide the evidence for making control strategy and evaluating the control effect. METHODS: A total of 22 national monitoring spots of soil-transmitted nematodosis were established according to the National Surveillance Program of Soil-Transmitted Nematodiasis (Trial), and the children aged 3-12 years were examined through adhesive cellophane anal swabs, thenthe infection rates of children with different ages, genders, nationalities and education levels were analyzed. In addition, the advantage, disadvantage, opportunity and threat of the monitoring work were analyzed by SWOT analysis. Results: A total of 17 068 children were examined in 22 monitoring spots from 2006 to 2010, and 1 363 of them were found being infected with E. vermnicularis, the average infection-rate was 7.99%, and the infection rates of male and female children were 7.39% and 8.70%, respectivel; the average infection rates in each year were 10.01%, 9.68%, 7.41%, 6.96% and 6.57%, respectively. From 2006 to 2009, the infection rates of E. vermicularis in children in Fujian Province was the highest, which were 56.15%, 53.42%, 37.82% and 49.53%, respectively, but in 2010, the infection rate in Guangdong Province (46.06%) was the highest. The fur- ther analysis demonstrated that the female children, 3-6 age group, Li nationality and children at kindergarten stage had relatively high infection rates. The SWOT analysis showed that the advantage of E. vermicularis monitoring in China was its wide coverage and continuity, and the disadvantage was the relatively small investment from the government, the opportunity was that the national monitoring Spot could drive the monitoring work at the provincial, county and other levels, and the threat was that the work was paid less and less attention to in recent years. CONCLUSION: Though the infection rate of E. vermicularis in children at national monitoring spots of soil-transmitted nematodosis has been decreased year by year, high-endemic areas still exist, and thus the work on enterobiasis control and prevention still needs to be strengthened.

[Survey of intestinal parasitic infections and related knowledge and behavior of residents in Jiaodong area of Shandong Province].

OBJECTIVE: To understand the status of intestinal parasitic infections and the related knowledge and behavior in residents of Jiaodong area of Shandong Province, so as to provide the evidence for making an appropriate preventive and control strategy. METHODS: A total of 18 villages from 6 counties in Jiaodong area were selected as investigation sites according to the stratified sampling method. The feces samples of the permanent residents aged above 3 years were collected and examined by Kato-Katz technique to find the intestinal parasite eggs, and the children under 12 years old were examined by the method of cellophane anal swab to detect the Enterobius vennrmicularis eggs. In addition, 50 households in each survey sites were randomly selected to investigate the basic family situation and the condition of awareness on prevention knowledge and formation of correct behavior of residents by using a structured questionnaire. RESULTS: Totally 6 163 residents involved in the feces examinations, and the total infection rate of intestinal parasites was 6.91%. The infection rates of Trichuris trichiura, Ascaris lumbricoides and hookworm were 6.56%, 0.62% and 0.21%, respectively. The infection rate of E. vermicularis in children under 12 years old was 0.51%. The eggs of Clonorchis sinensis and Taenia solium were not found in this survey. The awareness rate of knowledge about preventing parasitic diseases was 49.54%. The formation rates of washing hands before eating, washing hands after using the toilet, never eating raw fruit and vegetable without washing clean, never working in the field with bare feet, and never drinking unboiled water were 97.78%, 91.95%, 88.81%, 92.42% and 86.48% respectively. CONCLUSIONS: The infection rate of intestinal parasites is low in Jiaodong area, but there is a significant difference among different counties. The awareness rate of knowledge about preventing parasitic diseases is low, but the formation rate of healthy behavior is high. In the future, the health education and the strategy of taking medicine among the key population should be enhanced, and the project of reconstructing safe water supply and lavatory should be advanced.

Parasitic infections of the appendix as a cause of appendectomy in adult patients.

OBJECTIVE: Assessment of frequency and clinical findings of parasitic infections for etiology of acute appendicitis. METHODS: Data of 1452 patients who were carried out appendectomy between January 1999 and December 2012 were analyzed retrospectively. Appendectomy was performed in 1159 of the patients with a pre diagnosis of acute appendicitis. Demographics, physical findings, radiologic and laboratory studies, operative findings, pathological results, presence and type of parasitosis were investigated. RESULTS: Among the 1159 patients done appendectomy with a pre diagnosis of acute appendicitis, 719 (62%) were males and 440 (38%) were females. Parasitic infection was demonstrated in 17 (1.4%) of them. Mean average age of these patients was 36.6 ± 20.1 years. Enterobius vermicularis was present in 15 (88.2%) and Entamoeba histolytica in 2 (11.8%) of the patients. Of the pathology specimens of appendix consisting Enterobius vermicularis, 12 (80%) were normal appendix tissues, 1 (6.6%) was acute uncomplicated appendicitis and 2 (13.3%) were perforated appendicitis. One (50%) of the two specimens consisting Entamoeba histolytica was normal appendix and the other (50%) was acute appendicitis. CONCLUSION: Differential diagnosis of parasitic infections in etiology of acute appendicitis should be made properly. It must be remembered that this attention can save patients from a negative laparotomy and morbidity and mortality of it.

Effect of fenbendazole on an autoimmune mouse model.

Fenbendazole is an anthelmintic drug widely used to treat and prevent pinworm infection in laboratory rodents. Data regarding possible side effects of fenbendazole on the immune system are conflicting, potentially due to the design of treatment protocols. The purpose of the current study was to determine the effects of 2 fenbendazole therapeutic regimens (continuous for 5 wk and alternating weeks [that is, 1 wk on, 1 wk off] for 9 wk) on the development of autoimmune disease in (NZB × NZW)F1 mice. No significant differences in survival curves or weight were observed between the treatment groups and cohort mice receiving nonmedicated feed. At the termination of the experiment, there were no differences in tissue pathology. Hematocrit decreased and BUN increased over time in all groups, but no significant differences were present between groups. After the cessation of treatment, mice fed the medicated diet continuously for 5 wk showed an increase in antiDNA antibody. Although this difference was significant, it did not affect survival curves or disease-related tissue or blood changes. These data indicate that common protocols of fenbendazole treatment do not alter the progression of autoimmune disease in (NZB × NZW)F1 mice.