ANTIBIOTICS, VIRUSES, AND PHAGES 



165 



antibiotics J this was found to be true of penicillin and clavacin against 

 fowl pox inoculated into the chorioallantoic membrane of the chick 

 embryo (784). Penicillin was also found (707) to be without effect on 

 the virus of vaccinia, encephalitis, and equine encephalonigelitisj how- 

 ever, it had an effect, when used in large doses, on the course of infec- 

 tion of chick embryos with psittacosis and meningopneumonitis. The 

 possible effect of other antibiotics, such as aspergillin, upon certain 

 viruses has also been indicated (375). 



In a study of phage inactivation, it was found that streptothricin, 

 streptomycin, and clavacin exerted an effect, whereas penicillin and 

 actinomycin did not. There was no correlation between the suscepti- 

 bility of the host cells and that of the phage to an antibiotic agent. In the 

 case of E. colt host and phage, a concentration of the antibiotic great 

 enough to inactivate all the viable cells showed progressive decrease 

 in 24 hours of phage added to such mixtures. With lower concentra- 

 tions of the antibiotic, the phage multiplied only when the cells were 

 increasing. Phage in suspensions of streptomycin-treated cells was not 



TABLE 31. EFFECT OF PENICILLIN AND STREPTOMYCIN ON S. AUREUS 

 PHAGE AND ITS HOST. RESULTS X 10° 



From Jones (476). 



* Number of cells at start, 



