Abstract Body

Blastocystis is one of the most common intestinal parasites in humans in developing and developed countries in the world. However, the role of Blastocystis as a pathogen is still controversial, mainly because it is found in both patients suffering from intestinal symptomatology, such as diarrhea, flatulence, bloating, or abdominal discomfort, as well as in healthy people. Molecular characterization to identify subtypes present in samples is critical to unravel Blastocystis epidemiology and to characterize subtype level differences in host specificity, transmission, public health significance, and pathogenicity. Mixed subtype infections are often overlooked in molecular studies of Blastocystis, and a better characterization of these infections is needed to fully understand the epidemiology of Blastocystis. A high degree of genetic diversity has been found among Blastocystis isolates based on nucleotide differences in the small subunit (SSU) of the ribosomal RNA (rRNA) gene. Accurate assessment of Blastocystis subtype (ST) diversity is crucial to understanding epidemiology and sources of Blastocystis transmission to humans. The next-generation sequencing (NGS) improves the detection of mixed subtype infections and low abundance STs. NGS technology contributes to our understanding of the epidemiology of Blastocystis infection in humans and its zoonotic potential. In addition, it can be used to shape future studies which aim to better characterize the transmission pathways. Moreover further case-control studies implementing high-resolution molecular tools are necessary to understand the role of Blastocystis in health and disease. NGS data will be provided great benefit to the One Health approach for this protist.