Blastocystis hominis  Blastocystis hominis is a parasite that is
found throughout the world. Little is known about how it is
transmitted to humans. Some people who are infected have
symptoms and some do not. Treatment is available but is not
always  Watery or loose stools, diarrhea, abdominal pain, anal
itching, weight loss, and excess gas have all been reported in
persons with Blastocystis infection. Many people have no
symptoms at all.   The taxonomic classification of Blastocystis
hominis is mired in controversy.  It has been previously
considered as yeasts, fungi, or ameboid, flagellated, or
sporozoan protozoa.  Recently, however, based on molecular
studies, especially dealing with the sequence information on the
complete SSUrRNA gene, B. hominis has been placed within an
informal group, the stramenoiles (Silberman et al. 1996).
 Stramenopiles are defined, based on molecular phylogenies, as a
heterogeneous evolutionary assemblage of unicellular and
multicellular protists including brown algae, diatoms, ch