Pneumonic plague: Infection of the lungs by Yersina pestis, the bacterial agent that causes the plague, a disease of animals (rodents and their fleas) and humans.
The first signs of the pneumonic plague are fever, headache, weakness, and cough productive of bloody or watery sputum. The pneumonia progresses over 2 to 4 days and may cause septic shock and, without early treatment, death.
Person-to-person transmission of pneumonic plague occurs through respiratory droplets, which can only infect those who have face-to-face contact with the person who is ill.
Early treatment of pneumonic plague is essential. Several antibiotics are effective, including streptomycin, tetracycline, and chloramphenicol.
There is no vaccine against plague but prophylactic antibiotic treatment for 7 days will protect persons who have had face-to-face contact with infected patients.