It is and will remain the eternal parasite, a parasite that is spreading like a harmful bacillus more and more," Hitler's Mein Kampf says about the Jews anticipating their annihilation.

This crime against humanity is closely linked to the long history of the parasite.

An ancient term, which is shaped equally by scientific and social resentments and still has to be used to stigmatize people.

That could now change because biological parasites are increasingly recognized as ecologically indispensable and worthy of protection.

Assuming that the bioparasite succeeds in saving our honor, will the universal enemy image of the “social parasite” also die out?

Or do political and social struggles need the all-purpose metaphor of the freeloader?

The origin of the term parasite lies in ancient Greece, where the parásitos ate at temple festivals at the table of the priests: a blackhead.

"It didn't have negative connotations, but it was charged in a religious context," says Andreas Musolff, who researches, among other things, the change in the parasite image at the University of East Anglia.

In ancient Rome, however, the now Latinized parasitus mutated from a sort of job title to a fawning comedy character.

This is considered the first parasite term - character flaws included.

"He did little dirty things for his masters," explains Musolff.

"Annoying and grotesque, but nobody would have thought that these humorous characters should be eradicated.

A kick in the butt or a rebuff was enough.”

The parasite as a sycophant comedy character

Only with the rise of today's life sciences from the 18th century onwards did the discussion of the parasite become a question of existence.

For now the order of things willed by God seemed threatened.

According to the prevailing view, life was hierarchical and strived for progress, i.e. more complexity.

Parasites, with their often extremely simplified physique, were considered a step backwards in development and a danger to the structure of nature.

The consequence was clear: the "degenerate" parasites, who lived off the fruits of other people's work, had to be fought with all means.

The reduction is just an adaptation: Intestinal worms, for example, don't need legs, armor or a real head because they don't have to walk, defend themselves or think deep thoughts.

Nevertheless, there can be no question of lazing around, freeloading is stressful.

In fact, the vast majority of parasites fall by the wayside because they are eaten themselves, cannot find a suitable host or are dismantled by the body's defenses.

Like all living things, parasites struggle to survive and reproduce.

But they alone are measured with all too human moral concepts, often branded as devious and insidious.