Identification of novel Cryptosporidium species in aquarium fish

Little is known about the prevalence and genotypes of Cryptosporidium in fish. The present study investigated the prevalence of Cryptosporidium species in 200 aquarium fish of 39 different species in Western Australia by PCR amplification at the 18S rRNA locus. A total of 21 positives were detected by PCR (10.5% prevalence) from 13 different species of fish. Nineteen of these isolates were successfully sequenced. Of these, 12 were similar or identical to previously described species/genotypes of Cryptosporidium, while the remaining seven isolates appeared to represent three novel species.