Molecular identification of a rare subtype of Cryptosporidium hominis in infants in China.

Two Cryptosporidium isolates from separate infants suffering from diarrhea were obtained from a hospital in Zhengzhou, China and were genotyped by PCR amplification and sequence analysis of the small-subunit ribosomal RNA (rRNA) (SSU rRNA), 70-kDa heat shock protein (HSP70), and actin genes. Further subtyping was performed by PCR amplification and sequence analysis of the 60-kDa glycoprotein (gp60) gene. Both the isolates were identified as Cryptosporidium hominis subtype IdA21, a rare subtype previously found only in a human immunodeficiency virus-infected child in South Africa and another child in Jordan.