The fox tapeworm is a parasite that not only affects the fox. It often affects hunting domestic cats, and less commonly dogs and humans. The development cycle of the fox tapeworm mainly takes place in a cycle among wild animals. The fox as the final host carries
the sexually mature worm and excretes tapeworm eggs. Mice and other small rodents ingest the eggs with their plant food, thus becoming infected intermediate hosts. The tapeworm larva develops in their organs.
The small rodents are now eaten by the fox as its main prey. Here the circle closes: the tapeworm fin enters the final host, in whose intestine it develops into the sexually mature tapeworm. Since dogs and cats also eat infected mice, they also become definitive hosts in whose small intestine the fox tapeworm lives. But you don’t notice this as a pet owner until intestinal inflammation, diarrhea, emaciation or dull fur appear.
Humans as a false intermediate host
Dangerous are the excretions of dogs and cats, because by licking the microscopic eggs get into the fur – when stroking then to the hand of the human and from there finally into the mouth – if you do not wash your hands.
In the development cycle of the fox tapeworm, humans are a false intermediate host because they cannot pass on the infection to a final host. However, larval development takes place in his organs – as in true intermediate hosts. Primarily the liver and lungs are infected.
The larvae grow very slowly and destroy the organ like a tumor; the incubation period is five to 15 years. For humans, the fox tapeworm infection is therefore very dangerous, a cure is hardly possible. How many people are actually infected can only be estimated because of the long incubation period: the Bavarian State Office for Occupational Safety, Occupational Medicine and Safety Engineering states that 0.02 to 1.2 cases per 100,000 inhabitants are expected for Central Europe.
Danger from eating berries and mushrooms
Up to 200,000 tapeworms can live in one fox. Infested animals excrete tapeworm members with their feces, which contain several hundred tapeworm eggs. Tapeworm eggs can also stick to fruits growing close to the ground, such as berries and mushrooms, making them a dangerous source of infection for humans. Fruits growing low to the ground should never be eaten unwashed: it is best to heat them above 60 degrees – deep freezing alone will not kill the eggs.
Dog tapeworm
The dog tapeworm is a close relative of the fox tapeworm. Again, humans are intermediate hosts. The disease, called cystic echinococcosis, is triggered by the larvae of this two- to six-millimeter tapeworm. It is diagnosed relatively frequently in humans: According to information from Bayer Health Care, there are between 50 and 100 cases per year in Baden-Württemberg, for example. The reason: many dogs come to Germany from Mediterranean countries. There, up to 50 percent of dogs suffer from dog tapeworm.
As in the case of the fox tapeworm, the fin of the dog tapeworm settles primarily in the liver, lungs, and less frequently in the spleen, kidneys, brain and other organs. Although the infection is usually accompanied by no symptoms, symptoms can appear in the course. Abdominal pain is almost always a first symptom.
Sometimes, extensive infestation also results in yellowing of the patient’s eyes and skin. Bursting of the fins in the lungs means pain, coughing and difficulty breathing. If pathogens are found in the brain and spinal cord, neurological symptoms such as visual disturbances or paralysis may occur. In addition, there is a risk of allergic shock when fins burst.
