Assessment Of Different Stains And Staining Procedures For Microscopic Detection Of Malaria Parasites

Abstract

This study was carried out during the period from July 2002 to September 2003 in order to assess the use of different stains and staining procedures in microscopic diagnosis of malaria. A total of 203 individuals were included in the present study, Field-stained thick blood smear, Giemsa-stained thick and thin blood smears and Saponin lysed Giemsastained smears were prepared from each individual. Three different technicians examined stained blood smears independently. The result showed superiority of Giemsa-stained thick blood smears in detecting malaria parasites over others stained smears. Using Giemsa-stained thick blood smears malaria parasites were detected in 31, 32.5, 33 % whereas it was detected in 28.6, 29.5,30%, by Saponin lyzed venous blood smears and only in 26.1, 27.1%, 27.1% of Field stained smears as examined by three technicians. Further, three stocks solutions of Giemsa stain prepared by different methods were evaluated in staining blood smears, the finding showed a comparable result between the three Giemsa stain stock solutions. Unsatisfactory results were obtained when higher concentrations of Giemsa working solutions (15% & 20%) were used for shorter staining period versus convential concentration (10%). Adequate results were obtained by working solutions of Giemsa stain prepared using distilled water instead of phosphate buffered solutions, whereas poor results were obtained when a tap water was used. The study findings showed that it is possible to obtain Giemsa working solution with satisfactory staining properties, which did not decrease during the first 3 hours of preparation.