Cryptosporidium infection in humans and animals from Iraq: A review

Abstract

The apicomplexan parasite Cryptosporidium causes serious diarrheal disease in humans and animals worldwide. The present review summarizes epidemiological and molecular studies as well as the clinical disease burden of natural Cryptosporidium infections in humans and animals from Iraq. Retrieved reports regarding cryptosporidiosis in Iraq indicated that the disease is highly prevalent in humans and animals, but the results extracted from these reports are confusing and mostly employed traditional methodologies for the detection of Cryptosporidium infective stage, the oocysts, in clinical samples. Many screened surveys represent point prevalence studies, which described diarrhea in infants and children due to cryptosporidiosis; however, other pathogens causing diarrhea were not excluded. High prevalence of Cryptosporidium oocysts was recovered from many studies from different environmental matrices in different parts of Iraq including drinking tap water, which facilitates its transmission to humans and animals. Reports on molecular characterization of different Cryptosporidium species which exist in Iraq are few but both Cryptosporidium hominis and Cryptosporidium parvum were detected in humans and the latter was more prevalent in isolates from cattle, sheep, goats and birds. A national study on adequate numbers of samples from different hosts and environmental matrices, and employing advanced diagnostic methodologies is required to precisely detect the epidemiological situation of cryptosporidiosis in Iraq. Furthermore, molecular genotyping studies are required to be conducted in Iraq to characterize the species and subtypes of Cryptosporidium infecting humans and animals especially during outbreaks. Therefore, Cryptosporidium parasite should be included in the routine diagnosis and surveillance system of infectious diseases in Iraq and should be regarded as an important public health problem of concern.

Keywords: Animals; Cryptosporidium; Cryptosporidium parvum; Diarrhea; Human; Iraq.