Quite right, You made some excellent points about parasites. Mentioned in another post, I stated that the term 'parasite' is a very broad term. However, it is befitting of the description because parasites come in many forms. As part of this, all diseases 'may' be differing symptoms of fungus/mold/fermentation infections. It's another parasitic form.

We know that fungus is ubiquitous among us... (regretting the rhyme). Nevertheless, every cell in our body is born with fungus in them. It's another world of checks and balances in our bodies at every instant of time. I wonder sometimes whether cosmic fungus entering into the world was the Creator's punishment as a result of the original sin. Fungus is integral to aging, every process, resisting every step of the way, When it starts winning, this when we see disease.

When the body's immune system is compromised, it's like you stated, 'parasites' are able to infiltrate and under the right circumstances, able to multiply. Whatever form the parasite might be, it leaves a toxic brew of secretions damaging and killing cells. When a large number of cells die at once, it is called 'necrosis'. The dying cells is when the fungus in the cell is freed to multiply and causes fermentation within the cell. If you think about it in regards to Nature, this is part of the process of decay. Every living creature in Nature is subject to this.

Returning to the fermentation process in the dying/dead cell. it continues until the outer membrane of the cell finally ruptures. The aftermath of this is "budding" and this can be seen with a microscope.

Now, this is one aspect of the process. Another process is for normal cells to package up all the toxins that enter the human body from the outside environment. The remarkable process is that our cells continuously package up these toxins in proteins called 'exosomes' and then eject them out of the cell. Our excretory system rids the body of theses exosomes. When there are an excess of exosomes leaving the body, it shows up as systems of disease. Part of the excretory system is sneezing, coughing, sweating, exhaling, etc. When we are overloaded with exosomes, our excretory system accelerates and amplifies. What virologists call viruses may really be exosomes. The virus theory is only a working theory that has been accepted by the scientific community at large. Earlier I mentioned the term, "budding". This is the point that Virologists say, "Look, it's the virus." Except, it's not a virus at all. This 'budding' consists of fermented and toxic substances that act to signal 'clean up' cells for cleaning up cells. These clean up cells are exosomes that travel throughout the body.