Molecular Identification of Cryptosporidium spp. and Giardia spp. in Wild Birds in Southeastern Brazil

Abstract

Introduction: The identification of Cryptosporidium spp., Giardia spp. and Enterocytozoon bieneusi in birds is relevant since these animals can act as disseminators of these parasites to humans through environmental contamination. The aim of this study was to determine the molecular occurrence of Cryptosporidium spp. and Giardia spp. in wild birds in southeastern Brazil and genetically characterize the isolates obtained. Methods: A total of 256 fecal samples were collected from 172 captive and 84 free-living wild birds. The DNA extracted was subjected to nested-PCR and semi-nested PCR analysis for amplification of fragments of the 18S rDNA and gdh genes of Cryptosporidium spp. and Giardia spp., respectively. Results: With respect to Cryptosporidium spp., the overall occurrence was 3.91%. Of samples from captive wild birds, six (3.49%) were positive: two waterfowl and four non-aquatic birds. Among the samples from free-living wild birds, four (4.76%) were positive, all non-aquatic birds. Regarding Giardia spp., the overall occurrence was 3.1%. Of samples from captive wild birds, four (2.32%) were positive, all waterfowl; of the samples from free-living wild birds, four (4.76%) were positive for the parasite, all non-aquatic birds. Conclusions: The presence of C. meleagridis and G. duodenalis assemblage B suggests that epidemiological studies involving wild birds and humans are needed to better understand the impact of avian cryptosporidiosis and giardiasis on avian health and their possible implications for public health.