Tehran University of Medical Sciences Iranian Journal of Parasitology 1735-7020 6 3 2011 09 15 107 112 EN S Teimoori Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran MJ Gharaguzlu Department of Pathology, Faculty of Veterinary Medicine, University of Tehran, Tehran Iran MS Makki Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran F Shahbazi Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran I Mobedi Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran AA Saboor Yaraghi Department of Nutrition and Biochemistry, School of Public Health, Tehran, Iran Gh Hasanpour Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran MB Rokni Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran AND Center for Research of Endemic Parasites of Iran (CREPI), Tehran University of Medical Sciences, Tehran, Iran Gh Mowlavi Department of Medical Parasitology and Mycology, School of Public Health, Tehran University of Medical Sciences, Iran 2015 10 03 Background: Due to scarcity of human reports, we took advantage of the heaviest infection of M. moniliformis in rats, to describe histopathological and microanatomical valuable useful keys while confronting human occurrences. Methods:  Samples were obtained from captured rats in Tehran, capital of Ira, during two dec­ades.  Tissue sections were performed through hematoxylin and eosin staining to describe histopa­thological changes in rat's intestines. Results:  Totally, nine rats were found infected with M. moniliformis amongst 272 obtained rats. Heavy infection has been distinguished in 2 individuals with parasite burden of 141and 73 adult worms. Cross sections of worms within the lumen show mucosal thickness, infiltration of eosino­philic leukocyte and increase in goblet cells.   Conclusion:  Beyond the uncommonness of human infection with M. moniliformis unintended infections should not be ignored. Abundance of rats and roaches as definite and intermediate hosts must be considered particularly in countries with poor hygiene. https://ijpa.tums.ac.ir/index.php/ijpa/article/view/196 https://ijpa.tums.ac.ir/index.php/ijpa/article/download/196/195