Parasitology Training Manual

Wetmount/Concentrate Scanning Technique

The following is a demonstration of one of the scanning techniques for the examination of a direct wet mount or concentrate.

Slide scanning technique

Scan the entire coverslip systematically overlapping fields using the 10X objective(above illustration). Look for ova, larva and the larger cysts. With experience the finding of cysts such as Giardia lamblia and others are possible. If you suspect you have recovered a cysts or trophozoite drop down to a higher magnification (100X) to investigate further. Do not hesitate to place a drop of oil on the coverslip. If the mount is damaged you can always prepare another wet mount.

A small portion of the slide perhaps 1/3 should be scanned using a higher magnification. Try to get into the habit of making final identifications using a higher magnification. Always measure your findings. Measure, measure and measure again. Compare your findings with the various charts available. If at any time you are doubtful please ask a colleague for help.

CMLTO Recommendations for Parasitology Workloads

Experienced, competent MLT's should spend an average of 9 minutes screening a wet mount from concentrate before considering it negative.

For a complete copy of the Workload Guidelines for Parasitology Technologists you can contact the CMLTO