Molecular Study of Cryptosporidium spp. in Dogs from Southwest of Iran

Background: Cryptosporidium is a protozoan parasite that effects rodents, dogs, calves, humans, and cats. Infection with this parasite is known as cryptosporidiosis. Cryptosporidium spp. may induce clinical or subclinical signs in infected hosts. In the life cycle of this parasite infected dogs freely living in urban and rural areas of Khuzestan province are the definitive hosts that should be considered as a real problem in public health for humans. Objectives: This study aimed at determining the frequency of cryptosporidiosis in dogs in southwest of Iran. Methods: Overall, 350 fresh fecal samples were collected from domestic dogs living in 43 villages, from June 2012 to September 2013. All samples were investigated by Sheather's concentration method and fecal smears were stained with modified Ziehl-Neelsen followed by light microscope examination, and polymerase chain reaction (PCR). Results: The results revealed that frequency of Cryptosporidium infection was 8% and 12.3%, using direct smear and molecular method, respectively. Conclusions: The present findings indicated that domestic dog feces from southwest of Iran may contain zoonotic parasites such as Cryptosporidium spp. and may be a potential risk for humans and other animals, especially when they contaminate the environment. The role of dogs as source of human infection should be investigated by further studies.