Common occurrence of Cryptosporidium hominis in asymptomatic and symptomatic calves in France

摘要

Author summary Symptomatic infection by the Apicomplexan Cryptosporidium spp. is presently considered the most frequent parasitic cause of acute diarrhea in both humans (especially severe in immunocompromised individuals and infants in both developed and developing countries) and cattle (calves), while asymptomatic infections are less often documented. Cryptosporidium (C.) hominis once considered to be restricted to humans accounts for the majority of pediatric cases in several countries. C. parvum can also infect cattle as well as C. bovis, C. andersoni, and C. ryanae. Recently, cattle C. hominis cryptosporidiosis has been reported, suggesting that the presence of C. hominis in calves was previously underestimated. The aim of this work was to characterize Cryptosporidium spp. infection in both asymptomatic and symptomatic dairy and beef calves from Metropolitan France. From February to November 2015, C. parvum or C. hominis infected calves were detected in farms from 5 geographic regions of France. Surprisingly, C. hominis was present in about one fifth of Cryptosporidium spp. infected calves, and exhibited genotypes which were previously reported in human and nonhuman primate. Further investigations are aimed at documenting direct or indirect C. hominis transmissions between and among livestock and humans.