The swabbing up method (SW technique) was investigated, in an attempt to use the results of this technique in detecting the exact degree of microbiological cleanness of bioclean rooms (BCR) used for treatment of patients with acute leukemia. This method was compared with the agar sausage method (AS technique).
The bacterial contamination status as detected by these methods was categorized into 5 classes, depending on bacterial counts (Cn) per 100 cm2: Bioclean index class (BC) 50 was given to Cn<50, BC 100 to 50≤Cn< 100, BC 500 to 100≤Cn<500, BC 1000 to 500≤Cn< 1000, and BC 5000 to 1000≤Cn<5000.
Bioclean maps were made for bioclean rooms, using these categories of bioclean status. In the map obtained by the results of the SW technique, contamination of BC 500 was most frequently seen at 34.5%, followed by BC 50 at 28.8%. The highest degree ofcontamination, BC 5000, was seen at 7.7%.
In the map obtained by the AS technique, BC 500 was also most frequently observed, and its incidence was 42.3%. This technique worked only in classes of less than BC 500, and did not work at all in the environment heavily contaminated. The effect of the AS technique was about 50% of that of the SW technique.
These results show that the SW technique works in wider ranges of bacterial contamination tha n the AS technique, and thus, produces more reliable results in detecting bacterial contamination. Bioclean maps as described in the present study ensure correct identification of the source of contamination, and thus, plays an important role in infectious control.
The effect of the SW technique in relation to that of the AS technique can be expressed by the regression equation of Y= 0.375X+ 0.990 (n=82, r=0.472), where X is bacterial counts as detected by the SW technique, and Y, those detected by the AS technique. The results of both techniques were significantly correlated (P<0.01).
