Epidemiology of Human Cryptosporidiosis in Brazil: A Systematic Review Highlighting Cryptosporidium parvum

Abstract

Cryptosporidiosis is a zoonotic disease of medical and veterinary importance caused by Cryptosporidium spp. This study conducted a systematic review to assess the occurrence and distribution of Cryptosporidium spp. in humans in Brazil, with emphasis on C. parvum. Following the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) protocol and using five databases, 3689 articles were screened, and 48 met the inclusion criteria. Most studies were concentrated in the Southeast Region, particularly São Paulo, while major gaps were identified in the North and Midwest Regions. The mean prevalence was 8.9% using direct methods and 52.2% using indirect methods, with the highest positivity reported in the Northeast Region. Microscopy was the most frequently employed diagnostic tool, although it showed limited ability to differentiate species. When combined with molecular approaches, C. parvum and C. hominis were identified as the predominant species. Infection was most common among children and immunocompromised individuals, especially those with HIV and kidney diseases. Overall, the findings highlight substantial research gaps regarding cryptosporidiosis in Brazil and its disproportionate impact on vulnerable populations. Expanding regional studies, integrating molecular methods for species characterization, and implementing targeted public health strategies are essential to improve epidemiological knowledge and guide prevention and control measures.