It is a process of elimination for we do not know what all we have.
The tools today, the refusal to get a diganosis by the cheapest means sonogram, string test etc. and all the problems getting a positive stool test requires a series of drugs to eliminate the worms and more drugs.
We know we have thread/pins and then we take meds and find we have others, we take myrrh and quassia and find others...it just goes on and on until we get rid of the massess to feel better and we must continue with maintenance.
Everyone is different. We may think we have only one parasite and then we take another drug or herb and find others and we keep fighting and researching to kill them before they destoy us.
It is strange and on an individual basis.