Université de Fribourg

Converging seasonal prevalence dynamics in experimental epidemics

Lass, Sandra ; Hottinger, Jürgen W. ; Fabbro, Thomas ; Ebert, Dieter

In: BMC Ecology, 2011, vol. 11, p. 14

Background Regular seasonal changes in prevalence of infectious diseases are often observed in nature, but the mechanisms are rarely understood. Empirical tests aiming at a better understanding of seasonal prevalence patterns are not feasible for most diseases and thus are widely lacking. Here, we set out to study experimentally the seasonal prevalence in an aquatic host-parasite system. The...

Université de Fribourg

Parasites promote host gene flow in a metapopulation

Altermatt, Florian ; Hottinger, Jürgen W. ; Ebert, Dieter

In: Evolutionary Ecology, 2007, vol. 21, no. 4, p. 561-575

Local adaptation is a powerful mechanism to maintain genetic diversity in subdivided populations. It counteracts the homogenizing effect of gene flow because immigrants have an inferior fitness in the new habitat. This picture may be reversed in host populations where parasites influence the success of immigrating hosts. Here we report two experiments testing whether parasite abundance and...

Université de Fribourg

Mixed inoculations of a microsporidian parasite with horizontal and vertical infections

Vizoso, Dita B. ; Ebert, Dieter

In: Oecologia, 2005, vol. 143(1), p. 157

Mixed infections, where more than one parasite genotype is present in a single host, have been suggested to be an important factor in host–parasite interactions. As the host represents a limited resource, co-infecting parasite genotypes are expected to be under resource competition. Competition will not only modify the survival of the co-infecting genotypes, but is also likely to affect...

Université de Fribourg

Within-host dynamics of a microsporidium with horizontal and vertical transmission: Octosporea bayeri in Daphnia magna

Vizoso, Dita B. ; Ebert, Dieter

In: Parasitology, 2004, vol. 128, p. 31-38

The fresh-water crustacean Daphnia magna may acquire an infection with the microsporidium Octosporea bayeri either by ingesting spores from the water (horizontally), or directly from its mother (vertically). Due to differences in the time and mechanisms of transmission, horizontal and vertical infections may lead to differences in the growth of the parasite within the host. This may influence...