SECONDARY BACTERIAL INFECTION IN MICE 



Table VI. Staphylococci recovered from the noses of mice after various periods 

 of hydrochloric acid treatment. All mice were nasal carriers of staphylococci before 

 acid treatment. Number of mice tested shown in parentheses. *Summer mice. 



staphylococci were isolated from the tissue, the nasal flora likewise 

 consisted of coagulase-positive strains. These data, in conjunction 

 with those above, implicate the respiratory tract (nares) as a pos- 

 sible focus from which secondary invaders arise. 



The data of Table V demonstrate that secondary invasion by 

 staphylococci in normal mice exposed to cold requires approximately 

 a week and appears toreach a maximum in 14 days. Prior treatment 

 of the mice with hydrochloric acid drinking water did not alter sig- 

 nificantly, moreover, either the incidence or timing of staphylo- 

 coccal involvement of deep tissue. 



In view ofthe above, and since it is well known (Taylor and Dyren- 

 forth, 1938) that acute cold adversely affects the upper nasal pas- 

 sages, this area was studied to determine if it might serve as a 

 possible portal for deep tissue invasion. 



Effect of acid water treatment on the per cent of mice with noses 

 positive for staphylococci. Table VI shows that the percentage of 

 mice with culturable staphylococci from the nose remains essentially 

 unaltered regardless of the experimental procedures to which the 

 animals are subjected. For example, hydrochloric acid drinking 

 water given for various periods upthrough 28 days did not lower the 

 per cent of staphylococcal nasal carriers among normal or Giorgio 

 fed mice. This is contraryto what was noted in the gut since it could 

 be freed of staphylococci following acid water treatment and then re- 



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