How to Diagnose Pneumonic Plague

The term plague may be used generically to refer to an epidemic of any disease. In a medical context, however, it refers specifically to infections by Yersinia pestis, a rod-shaped bacterium. This disease is known for its ability to kill vast numbers of people. Pneumonic plague is highly contagious and may be transmitted between humans through aerosol droplets. The following steps will show how to diagnose pneumonic plague.

Instructions

• 1

  Observe pneumonic plague to have an abrupt onset marked by chills and fever with chest pains, coughing, difficulty breathing and bloody sputum. Inflammatory swellings of the lymph nodes called buboes also may be present.

• 2

  Obtain a patient history. Pneumonic plague should be strongly considered if the patient is from an endemic area, has a fever and has a history of exposure to rodents.

• 3

  Run routine blood tests. Pneumonic plague causes an increase in the number of leucocytes and peripheral blood smears typically shows toxic granulations and Dohle bodies. Yersinia pestis frequently can be cultured from the blood smear.

• 4

  Use additional tests to assist in a rapid diagnosis. A direct immunofluorescence of a culture or fluid may help and a passive hemagglutination test of the patient's serum may detect a patient in the acute or convalescent stage of pneumonic plague.

• 5

  Confirm the presence of plague bacilli in a reference laboratory. In the United States, qualified laboratories are available only in endemic states and the United States Centers for Disease Control and Prevention.