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1) Wipe the end of finger with alcohol, 2) Wipe fingertip with coton, 3) Pierce fingertip with sterile disposable lancet, 4) Allow blood to flow, do not squeeze finger. 5) Spread drop of blood with the corner of another slide to drag an area about 1 cm in diameter. This is the thick smear. Newsprint is just visible through the smear. 6) Touch a new drop of blood (smaller than the first) with the edge of another slide. 7) Bring the edge of the slide with the new drop of blood to the surface of the first slide. Place it at the far end, and wait until the blood spreads along the edge. 8) Holding the slide at an angle of 45°, pull it forward rapidly.
Air dry, allowing 10 minutes for the thin smear and 30 minutes for the thick smear. Mark slide with patient identification and date and time of collection. This is usually done using a sharp pencil on the thin smear after it has dried.

Fix the thin with methanol or ethanol. Do not fix the thick smear. Prevent exposure of the thick smear to methanol or ethanol fumes.

Giemsa stain is prepared with water buffered to pH 7.2 and Giemsa concentrate. Giemsa powder requires too much work to dissolve properly. Do not shake the Giemsa concentrate as this will cause suspension of particulate matter in the stain resulting in artifacts on final slides. Do not use Wright’s or another stain if it leaves precipitates confusable with parasites. Filter stain only if necessary. Prepare Giemsa by mixing: 1 part Giemsa concentrate with 9 parts of buffered water (pH 7.2). If Giemsa powder is dissolved in alcohol, it is Wright’s stain.
Place slides flat in a staining rack and cover with 1-2 ml of Giemsa solution. Let stand for 10-20 minutes. Gently rinse until no more stain comes for into the buffer. Dry! With 200 negative high power fields, a thick is considered negative. Perhaps 100 fields will do.   

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