Zoonotic Cryptosporidium and Giardia infections in pigeons (Columba spp.) at a wildlife hospital in France: Occurrence and molecular identification.

The feral rock pigeon (Columba livia domestica) and wood pigeon (Columba palumbus) are ubiquitous species found in cities worldwide. Its interaction with humans, domestic animals and wild birds makes them potential carriers of transmissible pathogens, including zoonotic parasites. The aim of this study was to identify protozoan parasites belonging to the genera Cryptosporidium spp. and Giardia spp. in these two pigeon species hosted at the Wildlife Animal Hospital of the Veterinary School of Alfort, in France. Fecal samples from 367 pigeons (Columba livia and Columba palumbus) including a wide majority of juveniles, were collected and analysed using both direct immunofluorescence and molecular identification techniques, including PCR targeting the small subunit ribosomal RNA and the 60 kDa glycoprotein gene of SSU rDNA. Eighty-six and 12 fecal samples tested positive for Cryptosporidium spp. and Giardia spp. by immunofluorescence, respectively. Young pigeons appeared to be infected by Cryptosporidium spp. more frequently than adults. In addition, wood pigeons seemed to be infected by Giardia spp. more often, while rock pigeons had a higher occurrence of Cryptosporidium spp. Phylogenetic analysis revealed the presence of zoonotic species including C. meleagridis, C. parvum, and G. duodenalis assemblage B. As these species are known to infect humans, pigeons could represent a potential source of zoonotic transmission.