I don't believe in conspiracies, though I do believe that that profit drives behavior.
The studies you will find on pubmed are not just from our country. They are from many countries. Countries where parasites are readily acknowledged. Also, there are some that are not studies, but book entries in books as old as 100 years (1906 entries) on the "then" cures for parasites. So that is over 100 years worth of varying degrees of scientific information across a variety of parasites across a varitey of possible remedies / treatments, across many countries. That is why there is a lot of information.
The reason why western medicine doesn't recognize parasites? I think it is simply becuase doctors are very bad at finding them. They have NO idea of the statistics of how prevelant they are. I think in their heads Parasitosis is actually more prevelant than humans infected with parasites. Someone told them that Americans don't get parasites because of the water. :) But clearly many parasites are food born and zoonotic. Which we are at risk for here, especially with organic farming, the globalization of the food supply, and the extremely high prevelance of pets who live as companion animals in the home.
We are also at risk because we keep being told we are not at risk and Americans aren't taking the same precautions other people who understand the threat of parasites do, in other parts of the country. We don't wash our hands as well. We don't understand the importance of wearing shoes. We cook our food quickly. We don't blanch our vegetables and eat them raw. We don't soak our salad vegetables in vinegar solutions. We are not taught preventive practices.
In short, I think it is ignorance on the doctors part and ignorance on our part.