I'm trying to understand why some of us are infested with parasites and why some (supposedly) easily eradicated bugs are so infuriatingly hard to dispose of.

B. hominis is one suspect and I'd like to hear from anyone that has actually tested positive for it.

Another theory is that liver function and low stomach acid could be what opens the door to parasitic infections. Flukes maybe?

Why is it that some of us are infested with (as an example) pinworms but our partners have no symptoms and appear to be immune.


http://www.ncbi.nlm.nih.gov/pmc/articles/PMC268968/?page=1

.....B. hominis was found in the stools of 62 of 389 patients
(16%). In 43 of the 62 patients, the average number of
organisms was equal to or exceeded 5 per 40x field (range,
5 to 15; average, 8). The remaining 19 patients averaged
fewer than five organisms per 40x field.

.....A total of 15 other intestinal parasites were found in
conjunction with B. hominis in 20 of these 43 patients (Table
1). Entamoeba histolytica was recovered from 36 (9%) of the
389 patients and was associated with B. hominis in 11 cases
(chi-square test, P < 0.001). None of the other intestinal
parasites had statistically significant association with B.
hominis. B. hominis was recovered with only nonpathogens
in one case (Endolimax nana).