DIRECT WET SMEAR: Procedure (cont.)

5. If something suspicious is seen, the 40 x objective can be used for more detailed study. At least one-third to one-half of the coverslip should be examined under high dry power (total magnification of x 400) even if nothing suspicious has been seen.

6. Another approach is to prepare and examine the saline mount and then add iodine at the side of the coverslip. The iodine will diffuse into the stool-saline mixture, providing some stain for a second examination. Remember, the iodine will kill any organisms present; thus, no motility will be seen after the iodine is added to the preparation.