CLINICAL OBSERVATIONS. 185 



to the right of the stenuim. The heart sounds are rapid and 

 usually become feeble or embryocardiac in character toward the 

 end. In the early stages the secondary pulmonic sound may be 

 accentuated, but it soon becomes much less distinct. 



DIAGNOSIS. 



The diagnosis is usually clear from the bacteriological examina- 

 tion of the sputum in which the bacillus is found in enormous 

 numbers and in almost pure culture. A rise in temperature and 

 an increased pulse rate are usually the earliest symptoms observ- 

 able, but before the sputum appears the diagnosis may be doubt- 

 ful. An examination of the blood, either microscopically or by 

 culture, may reveal the diagnosis, since during the past epidemic 

 all the cases became septicemic. The blood should always be 

 examined early, by cultural methods, as in the primary septicemic 

 cases involvement of the lungs may not occur. The bacteriolog- 

 ical diagnosis is the only certain one for excluding pneumonic 

 infection due to microorganisms other than Bacillus pestis, but 

 from the general condition of the patient, in connection with the 

 absence of marked physical signs in the lungs, the diagnosis 

 of pneumonic-plague infection is often particularly suggested. 

 Labial herpes has not been observed in primary pneumonic 

 plague. The presence of numerous coarse, piping or sibilant 

 bronchial rales in the lungs is an argument against pneumonic- 

 plague infection. The sputum in pneumonic plague is not puru- 

 lent as it frequently is in catarrhal bronchitis or in bronchial 

 pneumonia, and it is not so tenacious and has not the rusty ap- 

 pearance of the sputum so often seen in croupous pneumonia. 

 The cough is usually not so painful as in croupous pneumonia. 



The duration of the disease is usually less than two days, though 

 many cases did not live longer than sixteen hours after the onset 

 of symptoms. Cases sometimes survived for three, and, more 

 rarely, for four days. In no case reported was the duration over 

 one week. 



PROGNOSIS AND TREATMENT. 



The prognosis is unfavorable. No cases in which the bacte- 

 riological diagnosis was complete were known to have recovered 

 during the Manchurian epidemic. 



No method of treatment appeared in any way to have been 

 successful. Treatment with serum seemed, in a few instances, 

 to have prolonged the duration of the illness. 



