[SAF--an alternative fixation solution for parasitological stool specimens].

A comparative parasitological study in 3 collectives using 2 different fixatives for stool samples (SAF and MIF) was carried out. The SAF fixative consistently showed a significantly higher sensitivity for parasitic protozoa than the MIF fixative (Entamoeba histolytica 90.0% vs. 64.4%, Giardia lamblia 97.7% vs. 64.4%), which was due to an increased detection of cysts of both species. No difference in sensitivity for helminths was found. The cheap, simple formula and, due to the absence of mercury, the low toxicity are further advantages of the SAF fixative. Moreover, contrary to the MIF fixative, the SAF fixative permits the use of a wide range of staining techniques starting from fixed specimens. These results led to the replacement of the MIF fixative by the SAF fixative at the Diagnostic Center of the Swiss Tropical Institute.