We examined stool specimens of 148 returning travelers front an outpatient
department for tropical diseases for the appearence of microsporidia using
light microscopy and PCR. Intestinal microsporidiosis was diagnosed for fiv
e patients by light microscopy and for nine patients by PCR. Some cases wer
e diagnosed only by PCR, indicating that the true prevalence has to be dete
rmined by highly sensitive techniques, such as PCR.