PhD defence C.E. (Niels) van Elk

This thesis deals with the pathology of stranded marine mammals.  Knowledge about diseases is important to conserve these species. Life at sea is as much under pressure as is life on land. Stranded marine mammals are the only source of data available to study diseases particularly in cetaceans. The research was a joint effort by SOS Dolfijn, the department of Viroscience of the Erasmus Universtitary Medical Centre  and the Dolfinarium in Harderwijk. SOS Dolfijn is a foundation that rehabilitates stranded small cetaceans, mostly harbor porpoises, and releases them if rehabilitation is successful. Animals that died during rehabilitation were send for necropsy to the Erasmus Medical Centre. 

The thesis contains two parts. First, an overview was made of causes of disease and death in stranded harbor porpoises along the Dutch coast. The results of this overview were compared to the results of previous similar investigations in other parts of the North Sea. Second, disease caused by  a number of individual pathogens, viruses and bacteria,  were investigated. A higher prevalence of fatal fungal infections in harbor porpoises along the Dutch coast, compared to  fungal infections observed in other regions of the North Sea, was the most concerning finding. This is a reason for concern as fungal infection in mammals usually only become serious if the immune-competence of the host is seriously diminished. New viruses were discovered. A new pestivirus and two new herpesviruses in harbor porpoises. One of these herpesviruses caused a fatale encephalitis.

Due to corona, the PhD defences do not take place publicly in the usual way in the Senate Hall or in the Professor Andries Querido Room. The candidates will defend their dissertation either in a small group or online.