Parasites have many definitions and different ways of affecting people. In previous articles, I have discussed parasites and their relationships to allergies, cancer and mental illness. So, what are parasites? Medical text books define parasites as plants or animals which live upon or within another at whose expense it obtains some advantage. Generally, it is reserved for animal species of protozoa, helminths and arthropods.

One dictionary definition supports this view of parasite: “(1) In biology, where one organism depends upon something else for existence or support without making a useful or adequate return.” A parasite can also be a virus, bacteria, fungus, plant, or animal. However, another dictionary definition of parasite defines it in a broad context of social interaction: “(2) A person who exploits the hospitality of the rich and earns welcome by flattery.”

Following the first definition above, parasites evolved billions of years ago from the beginning when life forms werepara evolved from the primordial organic soup of amino acids and nucleic acids. Scientists are now sequencing the full battery of genes and DNA in many microbes. They can detect the signs of the pathway that parasites have taken. Rickettsia prowazekii, a bacterium that causes typhus, has DNA which looks remarkably like the DNA in mitochondria, the organelles that provide for energy at the cellular level in humans. Somehow, about 3 billion years ago, the mitochondrial organelle evolved and fused in harmony with the eukaryotes which became plants, fungus and animals. Rickettsia evolved down the parasitic, infectious pathway to invade cells and cause disease.

Parasites have evolved to adapt to a new environment and a new host by selectively “degenerating”, i.e. eliminating, some traits and changing their anatomy over the course of their evolution. Parasites can reduce to a few essential functions for their own survival. Parasites can also castrate the host and control the sexual behavior of their hosts. They can send their hosts along destructive pathways by controlling their host’s instinctive survival behavior. Parasites are masters of chemical and biological warfare. They are masters of mind control and molecular mimicry. They have steered the course of evolution to the point where the majority of species are parasites.

There are about four thousand species of mammals but there are over five thousand species of tapeworms alone, at least which are known so far. Parasites may have pushed their hosts to become more genetically diverse. They may have caused their hosts to evolve in response to new adaptations of parasites. If the host cannot handle the parasite, the host dies and the parasite perishes with the host and ends the evolution. In this sense, the relationship of the parasite and the host are far more complex than you may have imagined. For more information, read the fascinating book, Parasite Rex, by Carl Zimmer and explore inside the bizarre world of parasites.

From the clinical point of view, parasites have been closely associated with every known disease from allergies, asthma, nutritional problems, irritable bowel syndrome, and cancer to mental illness.

Following the second dictionary definition, some animals are “social parasites.” Social parasites essentially do what any parasites do. They find the weakness in their host’s defenses and turn it to their own advantage. The cuckoo lays its eggs in the nests of other birds such as reed warblers. When a young cuckoo hatches, it proceeds to hurl reed warbler’s eggs to the ground. The reed warbler feeds the cuckoo anyway, even as it grows so large that it dwarfs its stepparent. The young cuckoo mimics the calls of many baby warblers and tricks the reed warbler to feed him. Once it is fully grown, the cuckoo flies off to find a mate, leaving the childless reed warbler behind.

In summary, parasites are one of the major driving forces behind evolution and force their hosts to adapt to new environments. Parasites influence their hosts from the DNA level on up to social interactions. Parasites can disrupt their hosts’ perception of reality to control the behavior of their hosts. In addition, the society in which we live is a macro-social organism which has its own parasites. Parasitic Mind Control is a new evolution of social engineering developing from commercial advertisements and political propaganda that try to persuade and coerce the thinking of the populace. Therefore, internal parasites and external parasites have a variety of impacts on different people depending on their experience.