PNEUMONIC PLAGUE has an acute course than other forms, over and is accompanied by a very high mortality rate. The incubation period of primary pneumonic plague rarely exceeds more than 1-4 days. It begins, as a rule, suddenly - with shivering, fever, headache, myalgia, weakness, nausea. The symptoms of pneumonia - cough with phlegm, chest pain, shortness of breath - usually appear on the second day of the disease. Blood spitting, growing respiratory disorders, heart failure, respiratory failure, shock are being observed. In primary pneumonic plague phlegm usually is watery or mucinous, foamy, with blood or visibly bloody.
A secondary pneumonic plague occurs as interstitial pneumonia. Phlegm is scanty and more dense and viscous than in primary pulmonary plague. It is believed that in this regard, patients are less contagious.