A study revealed that cyclosporiasis patients had a decreased level of CD3+ and CD4+, while CD8+ was normal [107]. 3.4.3. Recent Advances in Research Although the prevalence Src Bosutinib of cyclosporiasis among diarrheal patients can be considerable as documented in several provinces of China, few epidemiological surveys have been implemented and many techniques applied to cryptosporiasis have not been introduced to cyclosporiasis research. Consequently, one challenge in epidemiological surveys is the lack of sensitive techniques to differentiate C. cayetanensis from other intestinal protozoa. Indeed, misdiagnosis is common [108]. Humans currently are the only known host of C. cayetanensis. The lack of an animal model prevents studying this parasite [109]. To overcome this limitation, Ge and colleagues established a rat model for C.

cayetanensis. They first suppressed the immune system of rats using hydrocortisone or cyclophosphamide and then infected them with C. cayetanensis. The number of oocysts in stool gradually increased and reached a peak 5�C7 days after infection [110]. The susceptibility to C. cayetanensis infection is thought to be related to the status of the immune system. A series of relevant studies was performed in order to reveal the relationship between the likelihood of an infection and different immune status parameters [107,111,112]. It was found that among the infected, the titer of membrane interleukin-2 receptor, CD3+ and CD4+ was significantly decreased relative to non-infected individuals, while that of soluble interleukin-2 receptor as well as specific IgG and IgM were significantly elevated.

3.5. Blastocystosis 3.5.1. Parasite and Pathogenicity Blastocystis hominis is one of the most frequently diagnosed protozoan parasites in human faecal samples. It is found in both symptomatic and healthy individuals and therefore, its pathogenic potential is still debated [113]. Additionally, many aspects of this organism including its taxonomy, life cycle and mode of transmission continue to be controversial despite this parasite being first discovered in human faeces as early as 1912 [114]. The morphologic diversity of the organism and the low sensitivity of the generally used wet-mount detection technique add further difficulties to its study [113]. Most people carrying B.

hominis infections are asymptomatic while some show gastrointestinal symptoms including diarrhea, abdominal discomfort, abdominal pain or abdominal cramping and vomiting. Acute infections may cause watery diarrhea. In addition, fatigue, loss of appetite, bloating, and other non-specific gastrointestinal Cilengitide symptoms have been associated with B. hominis infections. 3.5.2. Epidemiology B. hominis is endemic across the World, with a focus in tropical and subtropical regions. The first national survey showed that the overall prevalence B. hominis in China was 1.3% [4].