Genetic classification ofCryptosporidiumisolates from humans and calves in Slovenia

Abstract

SUMMARY: To assess the importance of cattle as a source of human cryptosporidial infections in Slovenia,Cryptosporidiumisolates from calves and humans with cryptosporidiosis were characterized genetically by direct DNA sequencing, targeting a variable region of the 60 kDa glycoprotein (gp60) gene. In total, 15 genetic variants, designated ‘subtypes’, were identified, of which 7 were novel. In humans,C. hominisIa (subtype IaA17R3) and Ib (IbA10G2) andCryptosporidium parvumIIa (IIaA9G1R1, IIaA11G2R1, IIaA13R1, IIaA14G1R1, IIaA15G1R1, IIaA15G2R1, IIaA16G1R1, IIaA17G1R1 and IIaA19G1R1), IIc (IIcA5G3), and IIl (IIlA16R2) were recorded; this is the first record of the latter subtype in humans. In cattle,C. parvumIIa (IIaA13R1, IIaA15G2R1, IIaA16R1 and IIaA16G1R1) and IIl (IIlA16R2 and IIlA18R2) were recorded. Of the 15 subtypes identified, subtypes ofC. parvumIIa were the most frequently encountered (>90%) in both humans and calves. The present findings suggest that zoonotic transmission plays an important role in sporadic human cryptosporidiosis in Slovenia.