Pneumonic plague | |
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A scanning electron micrograph depicting a mass of Yersinia pestis bacteria | |
Specialty | Infectious disease |
Symptoms | Fever, headache, shortness of breath, cough, hemoptysis[1] |
Usual onset | 3 to 7 days[2] |
Causes | Yersinia pestis[3] |
Risk factors | Rodents[3] |
Diagnostic method | Sputum testing[1] |
Treatment | Antibiotics[1] |
Prognosis | Invariably fatal when left untreated[4] |
Frequency | Rare[2] |
Pneumonic plague is a severe lung infection caused by the bacterium Yersinia pestis.[3] Symptoms include fever, headache, shortness of breath, chest pain, and coughing.[1] They typically start about three to seven days after exposure.[2] It is one of three forms of plague, the other two being septicemic plague and bubonic plague.[3]
The pneumonic form may occur following an initial bubonic or septicemic plague infection.[3] It may also result from breathing in airborne droplets from another person or animal infected with pneumonic plague.[1] The difference between the forms of plague is the location of infection; in pneumonic plague the infection is in the lungs, in bubonic plague the lymph nodes, and in septicemic plague within the blood.[3] Diagnosis is by testing the blood, sputum, or fluid from a lymph node.[1]
While vaccines are being developed, in most countries they are not yet commercially available.[1][3] Prevention is by avoiding contact with infected rodents, people, or cats.[1][3] It is recommended that those infected be isolated from others.[2] Treatment of pneumonic plague consists of antibiotics.[1]
Plague is present among rodents in Africa, the Americas, and Asia.[3] Pneumonic plague is more serious and less common than bubonic plague.[1] The total reported number of cases of all types of plague in 2013 was 783.[2] Left untreated, pneumonic plague is always fatal.[3] Some hypothesize that the pneumonic version of the plague was mainly responsible for the Black Death that resulted in approximately 75 - 200 million deaths in the 1300s.[2][5]