Abstract
            Introduction: Cryptosporidiosis is a worldwide zoonotic disease that is caused by Cryptosporidium species and leads to acute or  chronic diarrhea and vomiting in patients. Due to the suitable conditions of East Azerbaijan province for parasite transmission,  the present study was performed to evaluate the prevalence of Cryptosporidium infection in patients with gastroenteritis referred  to hospitals and reference laboratories of East Azerbaijan province during 2018-2019.  
  Methods: A descriptive cross-sectional study was performed on patients with diarrhea who referred to hospitals and reference  laboratories of East Azerbaijan province during 2018-2019. In this study, 180 fecal samples were collected from patients  with gastroenteritis by cluster-random sampling. Stool samples were stored in 10% formalin and transferred to a parasitology  laboratory and examined for parasite contamination by modified acid-fast staining (Modified Ziehl-Neelsen) method. Data were  analyzed by chi-square test using SPSS.  
  Results: Out of 180 samples, the highest number of diarrhea samples belonged to the age group over 40 years (35.5%) and the  lowest belonged to the age group of 10-20 years (7.7%). Additionally, 56% of subjects were male and 44% were female. Of  these patients, 57.7% lived in urban areas and 42.3% in rural areas. Cryptosporidium was observed in 1.6% (3 cases) of patients  with gastroenteritis. There was a statistically significant relationship between Cryptosporidium infection and the age of patients  with diarrhea (P<0.05).  
  Conclusion: In the present study, a lower prevalence of cryptosporidiosis has been determined in comparison with previous  studies in East Azerbaijan province. However, Cryptosporidium and other parasitic infections in the feces of patients with  diarrhea referred to hospitals or reference laboratories need to be carefully diagnosed by appropriate parasitological methods.