Molecular characterization of Cryptosporidium parvum isolates from human cryptosporidiosis cases in Scotland

Cryptosporidium parvum (C. parvum) is one of the most prevalent protozoan pathogens responsible for inducing human and animal disease worldwide. In this study, the glycoprotein-60 (gp60) subtyping tool was employed to assess the molecular diversity of C. parvum from human feces throughout Scotland during potential outbreaks. Over a 24-month period, microscopy analysis revealed 1139 positive feces containing Cryptosporidium species with 256 identified by molecular methods specifically as C. parvum. Cryptosporidium parvum was shown to be more prevalent in rural areas of Scotland and subtyping of 87 isolates demonstrated the predominant family as IIa, which occurred in 94% (n = 82) of isolates. The IIaA15G1R1 subtype was most common, being isolated from 47% (n = 41) of Scottish human cases. Non-IIa strains constituted a total of 5 isolates and included subtypes from the IIc, IId and IIg families. This information contributes significantly to existing knowledge and understanding of C. parvum subtypes in Scotland which is vital in assisting with the management of future local and national outbreaks.