Abstract
Biological properties of airborne and human carrier staphylococci were investigated in order to examine their interrelationships. Airborne staphylococci were isolated by the impinger or pin-hole sampler method and carrier-borne were removed from the nose, hair and forearm skin of students by cotton-wool swabs. Coagulase test, deoxyribonuclease (DNase) test, lysozyme test, anaerobic mannitol fermentation test, α-hemolysin test and classification of colony type formation on serum-soft agar were carried out with these samples.
The results obtained are summerized as follows:
1. With the isolated airborne staphylococci colonies, coagulase positive and compact-type colony formation on serum-soft agar were very few, while DNase, lysozyme, mannitol and α-hemolysin were found in a high percentage. Airborne staphylococci showed characteristic patterns in their biological properties.
2. Carrier rates of coagulase positive and compact-type colony formation were higher when isolated from nose as compared with skin and hair. On the contrary, DNase positive rates were higher in hair and skin.
3. Human origin staphylococci in nose, hair and skin showed characteristic patterns in their respective biological properties. There was a wide difference between the biological properties of hair-borne and airborne staphylococci. However, staphylococci in skin and nose that had been isolated showed almost the same positive rates in each biological test when compared with airborne staphylococci except for coagulase and DNase, respectively.
These results suggest that variations in DNase and coagulase activities of staphylococci dispersed from skin and nose into the air are caused by environmental changes, and that airborne staphylococci show characteristic biological properties.
