The main theme in my work is to study how ecological factors can modulate the outcome of host-parasite interactions and the transmission, persistence and virulence of parasites. In my PhD-work I studied the transmission of a cestodan fish parasite which has a copepod as the first intermediate host and two coregonid fishes as second intermediate hosts. One of my questions was if the strong fluctuations in the abundance of the host which was less susceptible but a superior competitor could affect the transmission of the parasite to the host which was more susceptible but a poorer competitor.

Later on I have been using a model system consisting of Daphnia-waterfleas and their microparasites. I have been studying how nutritional stress, predation or host community structure affect the persistence and transmission of parasites in host populations or between individuals. The results of this work have shown that both nutritional stress and size-selective predation have a potential to constrain the occurrence and persistence of parasites in the host populations. Interestingly, as was shown for predation, they could also be a factor promoting a co-existence of a virulent parasite with its host. I have also shown that the presence of a conspesific, even a resistant one, can decrease the transmission of parasites between Daphnia individuals (dilution effect). My current project is studying the interactions between resource quality (in terms of C:N:P-ratios) and parasites in Daphnia waterfleas both in laboratory and in the field.  

In addition I am currently collaborating in research projects that study the evolution of virulence in a bacterial pathogen of fish and the effect of introduced signal crayfish on parasites of fish.