Pneumonic plague is a severe lung infection caused by the bacterium Yersinia pestis. Symptoms include fever, headache, shortness of breath, chest pain, and coughing. They typically start about three to seven days after exposure. It is one of three forms of plague, the other two being septicemic plague and bubonic plague.The pneumonic form may occur following an initial bubonic or septicemic plague infection. It may also result from breathing in airborne droplets from another person or animal infected with pneumonic plague. 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. Diagnosis is by testing the blood, sputum, or fluid from a lymph node.While vaccines are being developed, in most countries they are not yet commercially available. Prevention is by avoiding contact with infected rodents, people, or cats. It is recommended that those infected be isolated from others. Treatment of pneumonic plague is with antibiotics.Plague is present among rodents in Africa, the Americas, and Asia. Pneumonic plague is more serious and less common than bubonic plague. The total reported number of cases of all types of plague in 2013 was 783. Left untreated, pneumonic plague is nearly always fatal. 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.
Most of the infections in Peru were bubonic plague, with four cases of pneumonic plague.The first recorded plague outbreak in Peru was in 1903. Prior to the above case, the last known outbreak was in 1994, killing 35 people. Madagascar
In November 2013, an outbreak of plague occurred in the African island nation of Madagascar. As of 16 December, at least 89 people were infected, with 39 deaths with at least two cases involving pneumonic plague. However, as many as 90% of cases were later reported to have involved pneumonic plague.From 23 August to 30 September 2017, a total of 73 suspected, probable, and confirmed cases of pneumonic plague, including 17 deaths, were reported in Madagascar. The diagnosis was confirmed by the Institut Pasteur de Madagascar by a polymerase chain reaction test, while field health workers used a Rapid Diagnostic Test. The WHO and Institut Pasteur de Madagascar were both involved in administering antibiotic compounds and attempting to stop the spread of the disease. By mid-October, there were an estimated 684 confirmed cases of plague with 474 pneumonic, 156 bubonic and one septicemic. The remainder were not classified. At least 74 deaths have been ascribed to pneumonic plague.The outbreak officially ended on 26 November 2017 with 2,348 cases and 202 deaths officially reported. United States
In the fall of 1924, an outbreak occurred in Los Angeles that killed 30 people. On 2 November 2007, wildlife biologist Eric York died of pneumonic plague in Grand Canyon National Park.