Bubonic and septicemic plague are generally spread by flea bites or handling an infected animal.[1] The pneumonic form is generally spread between people through the air via infectious droplets.[1] Diagnosis is typically by finding the bacterium in fluid from a lymph node, blood or sputum.[2]
Those at high risk may be vaccinated.[2] Those exposed to a case of pneumonic plague may be treated with preventive medication.[2] If infected, treatment is with antibiotics and supportive care.[2] Typically antibiotics include a combination of gentamicin and a fluoroquinolone.[3] The risk of death with treatment is about 10% while without it is about 70%.[4]
Globally, about 600 cases are reported a year.[2] In 2017, the countries with the most cases include the Democratic Republic of the Congo, Madagascar and Peru.[2] In the United States, infections occasionally occur in rural areas, where the bacteria are believed to circulate among rodents.[5] It has historically occurred in large outbreaks, with the best known being the Black Death in the 14th century, which resulted in more than 50 million deaths.[2]