Long-term molecular surveillance of Cryptosporidium and Giardia in wildlife in protected drinking water catchments

Abstract

Background: This study presents findings from a 15-year longitudinal surveillance program (2009–2024) monitoring Cryptosporidium and Giardia in protected drinking water catchments in Melbourne and environs in the State of Victoria, Australia. As one of the few major cities worldwide sourcing largely unfiltered water from forested catchments, Melbourne presents a unique opportunity to assess the occurrence and prevalence of protozoan parasites in a minimally disturbed ecosystem. Methods: A total of 14,960 animal faecal samples were analysed using polymerase chain reaction (PCR)-based sequencing, including 8695 samples collected over the past 9 years. Results: Cryptosporidium was detected in 3..