A bubo (Greek βουβών, boubôn, "groin") (plural form: buboes) is the swelling of the lymph nodes. It is found in infections such as bubonic plague, gonorrhea, chlamydia, tuberculosis, chancroid or syphilis. It is similar in appearance to a huge blister, and usually appears under the armpit, in the groin or on the neck.
According to historical records, buboes were characteristic of the pandemic responsible for the Black Death and perhaps other ancient pandemics. At the time of such pandemics, it was commonly believed by doctors that buboes should be burst; hen feathers were reportedly used for such a purpose. However, in modern medicine this treatment is regarded as useless and possibly harmful, as the puncture site could leave a patient at higher risk of infection.
Buboes rarely require any form of local care, but instead recede with systemic antibiotic therapy. In fact, for plague patients, incision and drainage poses a risk to others in contact with the patient due to aerosolization of the bubo contents. Needle aspiration can be performed for diagnostic purposes and may also provide symptomatic relief.