Trichinella

Owen, 1835

The genus Trichinella (trichinae) in the worm class of nematodes, contains as the most important human pathological species Trichinella spiralis and Trichinella britovi, both causative agents of trichinosis (trichinellosis), which, however, is now rare in Central Europe due to trichinella testing. In Eastern Europe and Greece (Dimzas D et al. 2019), smaller outbreaks have been recorded repeatedly in the past (Vutova K et al. 2020; Pavic S et al. 2020), with both species being equally detected. Apparently, deliberate "alternative" pig husbandry played a role in these outbreaks. In tropical areas, trichinella is not of great importance.

In principle, all mammals are susceptible, but natural infections are most likely in carnivores and omnivores such as the fox and the pig. In Central Europe, the red fox is considered the most important reservoir of the pathogen.

Humapathologically important species are:

• Trichinella spiralis
• Trichinella britovi

The clinical course depends on the number of incorporated Trichinella larvae. Already 50 larvae can cause clear clinical symptoms. With a larger number of larvae, there are considerable systemic reactions such as: like fever, intestinal colic, diarrhoea, muscle pain. Edema of the face (eyelid edema), macular exanthema, subungual splinter hemorrhages (see below Trichinosis).

In Germany and Switzerland, trichinosis (trichinellosis) in humans is notifiable.

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