Biological contamination of urban soils in Leicester, UK, with Cryptosporidium spp.: a pilot study

Environmental contamination with zoonotic microorganisms can have significant health and environmental implications due to their potential for producing large numbers of transmissive stages and their ability to survive in the environment for prolonged periods of time. This is especially relevant in urban environments because of the dramatic human population boom and urbanization. Cryptosporidium spp. is a zoonotic pathogen which can affect animals and humans. Although a major public health concern there is limited information about the occurrence and circulation of Cryptosporidium spp. in urban environments. 27 soil and animal faecal samples from birds, water birds, cats and dogs were collected in public parks and recreation areas in Leicester centre city between January and February 2016. Samples were collected on days with no rain to avoid problems of sample integrity. After appropriate preparation of each sample, detection of Cryptosporidium spp. was performed with the conventional parasitological technique of Kinyoun's acid-fast staining and the immunoassay ImmunoCard STAT!®. None of the 27 samples collected was positive for these emerging pathogens, although we found structures that may be related to Cryptosporidium in one of the faecal smears from a dog. Despite the preliminary data described indicating a limited presence of Cryptosporidium spp. in the public parks and recreational areas monitored, further more detailed knowledge of their circulation in these ecosystems will be crucial to assess the public risk to develop novel strategies to protect humans and increase the awareness of parasite contamination of our environment.