Plague

Capillary fragility is one of the manifestations of a plague infection, evident here on the leg of an infected patient.
Small hemorrhages on the skin of a plague victim
After the incubation period of 2-6 days, symptoms of the plague appear including severe malaise, headache, shaking chills, fever, and pain and swelling, or adenopathy, in the affected regional lymph nodes, also known as buboes.
Swollen, ulcerated cervical lymph node
This patient acquired a plague infection through abrasions on his upper right leg. Bubonic plague is transmitted through the bite of an infected flea, or as in this case, exposure to inoculated material through a break in the skin. Symptoms include swollen, tender lymph glands known as buboes.
Plague infection on the upper right leg
This patient presented with symptoms of plague that included gangrene of the right foot causing necrosis of the toes. In this case, the presence of systemically disseminated plague bacteria Y. pestis, i.e. septicemia, predisposed this patient to abnormal coagulation within the blood vessels of his toes.
Necrosis of the toes
This photograph depicts the shaved anterior thoracoabdominal region of a rock squirrel, Spermophilus variegatus, formerly known as Citellus variegatus, which is afflicted with the plague. This squirrel is displaying a petechial rash, which is similar in appearance to those found on humans also afflicted with Yersinia pestis. A petechial rash refers to small, pinpoint, flat lesions of the skin and mucous membranes that are associated with hemorrhages beneath the skin surface.
Anterior thoracoabdominal region of a rock squirre
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