title: Effect of climate change on runoff of Campylobacter and Cryptosporidium from land to surface water.
abstract: Faeces originating from wildlife, domestic animals or manure-fertilized fields, is considered an important source of zoonotic pathogens to which people may be exposed by, for instance, bathing or drinking-water consumption. An increase in runoff, and associated wash-off of animal faeces from fields, is assumed to contribute to the increase of disease outbreaks during periods of high precipitation. Climate change is expected to increase winter precipitation and extreme precipitation events during summer, but has simultaneously also other effects such as temperature rise and changes in evapotranspiration. The question is to what extent the combination of these effects influence the input of zoonotic pathogens to the surface waters. To quantitatively analyse the impacts of climate change on pathogen runoff, pathogen concentrations reaching surface waters through runoff were calculated by combining an input model for catchment pathogen loads with the Wageningen Lowland Runoff Simulator (WALRUS). Runoff of Cryptosporidium and Campylobacter was evaluated under different climate change scenarios and by applying different scenarios for sources of faecal pollution in the catchments, namely dairy cows and geese and manure fertilization. Model evaluation of these scenarios shows that climate change has little overall impact on runoff of Campylobacter and Cryptosporidium from land to the surface waters. Even though individual processes like runoff fluxes, pathogen release and dilution are affected, either positively or negatively, the net effect on the pathogen concentration in surface waters and consequently also on infection risks through recreation seems limited.
authors.affiliation: National Institute for Public Health and the Environment, Postbus 1, 3720 BA Bilthoven, the Netherlands.
authors.forename: Ankie
authors.initials: A
authors.lastname: Sterk
authors.affiliation: National Institute for Public Health and the Environment, Postbus 1, 3720 BA Bilthoven, the Netherlands; Utrecht University, Faculty of Geosciences, Department of Earth Sciences, Domplein 29, 3512 JE Utrecht, the Netherlands. Electronic address: Jack.Schijven@rivm.nl.
authors.forename: Jack
authors.initials: J
authors.lastname: Schijven
authors.affiliation: National Institute for Public Health and the Environment, Postbus 1, 3720 BA Bilthoven, the Netherlands; Utrecht University, Faculty of Veterinary Medicine, Institute for Risk Assessment Sciences, Domplein 29, 3512 JE, the Netherlands.
authors.forename: Ana Maria
authors.initials: AM
authors.lastname: de Roda Husman
authors.affiliation: National Institute for Public Health and the Environment, Postbus 1, 3720 BA Bilthoven, the Netherlands.
authors.forename: Ton
authors.initials: T
authors.lastname: de Nijs
mesh_terms: D000818:Animals; D002167:Campylobacter; D002417:Cattle; D057231:Climate Change; D003458:Cryptosporidium; D005260:Female; D014867:Water
chemical_list: D014867:Water
keywords: Climate change; Lowland catchments; Pathogen transport; Quantitative microbial risk analysis; Runoff