eDNA detection of aquatic diseases based on DNA fragments in environmental samples

Various aquatic animal diseases endanger Swiss fish and crayfish stocks. The most relevant among these are fish mold, proliferative kidney disease in fish (PKD) and crayfish plague in crayfish. All these diseases have a strong influence on the occurrence of the respective animals. All over Switzerland there is a lack of comprehensive knowledge of the distribution of these diseases, which hampers the ability to take measurements.

By using the eDNA method it is possible to detect diseases by means of DNA snippets occurring in water samples. This method of detecting pathogens or organisms has been in increasing demand for several years. In a project run in cooperation with Eawag, the method was established and validated over a period of three years, and subsequent monitoring of the diseases was carried out throughout Switzerland.