Efficacy of forage chicory, tannins and praziquantel against metacestode stage of Hymenolepsis diminuta (Cestoda) in the Tenebrio molitor (Coleoptera) an invertebrate – parasite model

Setaria tundra is a filarial nematode that is transmitted between several species of angulates through mosquitoes. Infections with S. tundra were previously described in European countries, including Fennoscandinavia. Setaria tundra inhabits the abdominal cavity of reindeer and is generally considered harmless but severe morbidity and mortality for both reindeer and moose were recently reported in Finland.

In this report, worms of S. tundra were recovered from three deer, one hunted in October 2010 in the eastern part of peninsular Jutland, a second deer was hunted in May 2011 in the south-west of the island, Zealand, and the third deer was hunted in May 2012 in the southern part of Zealand. The worms were identified as S. tundra based on morphology and/or molecular typing of the mitochondrial 12S rRNA and cox1 genes.

Roe deer are generally considered asymptomatic carriers of S. tundra, and the recovery of the worms indicates the presence of this parasite that is of high concern to breeders of roe deer and other ungulates. This parasite may have been present but overlooked. Previous outbreaks of setariasis in Scandinavia have been associated with marked climatic changes, such as unusually warm summers.

Given the right circumstances, the parasite has demonstrated capacity to a dramatic spread. The presence of highly populated deer farms may also enhanced the spread of this parasite. These facts highlights the importance understanding the ecological factors that might promote the expansion of this nematode may as well help to predict disease outbreaks of other filarial nematodes that utilize the same vectors.