A whole water catchment approach to investigating the origin and distribution of Cryptosporidium species

Abstract

Aims: Investigating the distribution and origin of Cryptosporidium species in a water catchment affected by destocking and restocking of livestock as a result of a foot and mouth disease epidemic. Methods and Results: Surface water, livestock and wildlife samples were screened for Cryptosporidium and oocysts characterised by sequencing SSU rRNA and COWP loci, and fragment analysis of ML1, ML2 and GP60 microsatellite loci. Oocyst concentrations in water samples (0–20·29 per 10 l) were related to rainfall events, amount of rainfall and topography. There was no detectable impact from catchment restocking. Cryptosporidium spp. found in water were indicative of livestock (Cryptosporidium andersoni and Cryptosporidium parvum) and wildlife (novel genotypes) sources. However, C. andersoni was not found in any animals sampled. Calf infections were age related; C. parvum was significantly more common in younger animals (<4 weeks old). Older calves shared Cryptosporidium bovis, Cryptosporidium ryanae and C. parvum. Wildlife shed C. parvum, Cryptosporidium ubiquitum, muskrat genotype II and deer genotype. Conclusions: Several factors affect the occurrence of Cryptosporidium within a catchment. In addition to farmed and wild animal hosts, topography and rainfall patterns are particularly important. Significance and Impact of the Study: These factors must be considered when undertaking risk‐based water safety plans.

First molecular characterization of Cryptosporidium and Giardia from bovines (Bos taurus and Bubalus bubalis) in Sri Lanka: unexpected absence of C. parvum from pre-weaned calves

“…GQ345008; [57]) and the UK (accession no. HQ822134; [58]), and also in water buffaloes in Australia (accession no. KF019204; [29]).…”

Enteric Protozoa in the Developed World: a Public Health Perspective

“…However, it has been suggested that these methods have limited usefulness in genotyping Cryptosporidium spp. in animals because of their narrow specificity (342,473). The disadvantage of some PCR tools is that they are designed to detect the dominant Cryptosporidium genotype in the specimen and require a substantial amount of PCR product to be visible on an agarose gel, and when specific genotyping and subtyping tools are used, they fail to detect concurrent infections with mixed Cryptosporidium species/genotypes or fail to detect other divergent species/genotypes (168).…”

Comparison of diagnostic sensitivity and specificity of seven Cryptosporidium assays used in the UK

“…We have also confirmed, using molecular methods, a variety of Cryptosporidium spp. in water samples, originally isolated using immunomagnetic separation and detected by IFM (Chalmers et al, 2010b;Robinson et al, 2011), suggesting that the antibodies in these tests have broad species specificity. Although cross-reactivity of several antibodybased tests has been demonstrated (Barugahare et al, 2011), the species specificity of antibody-based Cryptosporidium assays requires further investigation and this is under way at the Cryptosporidium Reference Unit.…”