Cryptosporidium in chickens during 2000 to 2025: A systematic review and meta-analysis of prevalence, species/genotypes distribution and zoonotic significance.

Cryptosporidium is an important avian pathogen. It can also be transmitted to humans through water sources contaminated with avian faeces or through direct avian-human contact. We conducted a meta-analysis to evaluate the global prevalence of Cryptosporidium in chicken. A total of 74 datasets from 21 countries/regions were used for the quantitative analysis. The prevalence of Cryptosporidium infection in chicken varied from 0.0% to 37.7%, with a summary estimate of 15.7% (3402/25,627; 95% confidence interval 14.0-17.4%). Nine Cryptosporidium species/genotypes were detected in chicken globally. Among the zoonotic Cryptosporidium species, Cryptosporidium meleagridis was the dominant species, followed by Cryptosporidium parvum. The isolates included 3 genotypes of C. meleagridis (IIIb, IIIe, IIIg), the proportion of subgenotype family IIIb of C. meleagridis was 45.6% (110/241). The results indicated that Cryptosporidium baileyi is the dominant species in Asia, while C. meleagridis is the dominant species in South America, with higher rates of Cryptosporidium noted in South America. Given that chicken has a substantial role in the global C. meleagridis zoonoses, and the need for further study of the prevalence, transmission, and control of this pathogen. This study assessed the global distribution of Cryptosporidium spp. in chicken, highlighting its zoonotic implications. It serves as a key resource for researchers, veterinarians and public health officials for future studies and control strategies.