Answer:
Yersina pestis
Step-by-step explanation:
Plague is a serious bacterial infection transmitted by the bacterium Yersinia pestis, present on all continents of the world except Oceania. Humans get the disease when they are bitten by an infected flea or come into contact with infected material, such as mucus.
Bubonic plague affects the lymph glands, causing swelling and inflammation in these areas, and causes very high fever in infected individuals. Coincidentally these are the symptoms, shown by the individual exposed in the question, so the doctor should test if the patient has the plague-causing agent, which is the bacterium Yersina pestis.