A Historical Overview of Research on , a Protozoan Parasite Infecting Water Buffalo.

is a globally important zoonotic disease caused by tick-borne intraerythrocytic protozoan of the genus (phylum apicomplexa). In China, there are five species that infect cattle buffalo and cause great economic loss, which include , , , , and . Among them, is the most recently identified new species epidemic in China. This review summarized the work done in the past 33 years to give an overview of what learned about this parasite. This parasitic protozoan was found in 1984 in Central and South China and then named as in 1997 based on its differences in transmitting host, morphology, pathogenicity and characteristics of cultivation when compared with and . It was found that is the transmitting vector and water buffalo is the only reported host. Phylogenetic analysis based on the 18S rRNA gene also confirmed that is a new species. After species verification, four diagnostic methods including semi-nest PCR, loop-mediated isothermal amplification assay, reverse line blot hybridization assay, and real-time PCR were established for lab and field use purposes. Genomic sequencing was conducted and the complete genomes of mitochondria and apicoplast were annotated. Future work will be focused on developing effective vaccines, identifying drug targets and screening useful drugs for controlling in water buffalo.