Transmission

           As stated earlier, Plague is caused by the bacteria, Yersinia Pestis. (“Plague” World of Health) “The bacteria Yersinia Pestis can also infect humans. It is transmitted between animals and humans by the bite of infected fleas, direct contact, inhalation, and rarely ingestion of infective materials.” (“Plague” W.H.O.) The Bubonic form of this disease is non-transferrable between humans. It is caused by the bites of rodents and fleas. The Pneumonic form is transferrable between humans and it spreads through the air. The worst of the three, the Septicemic form is spread directly through blood and other bodily fluids. If not treated, the Bubonic form turns into the Pneumonic form and then turns into the Septicemic form. Ground squirrels and prairie dogs also can contract this disease in parts of Arizona, New Mexico, California, Colorado, and Nevada. A person can become infected while handling these animals. (“Plague” World of Health) In prior times, people unknowingly spread the disease by burning incense, dipping handkerchiefs in aromatic oils, ringing church bells, firing cannons, wearing talismans, bathing in human urine, placing “stinks” (dead animals) in human dwellings, bleeding via leeches and bloodletting, drinking the pus extracted from a bubo, applying dried toads to relieve the pain of buboes, drinking liquid gold and powdered emeralds (only for the wealthy, of course), and joining groups of flagellants. There are multiple different types of contact a person can make to become infected with the disease. There is droplet contact which involves coughing or sneezing on another person. There is also direct physical contact which involves touching a contaminated person, including sexually. Indirect contact is when a person touches a contaminated surface. Airborne transmission occurs when the microorganism can remain in the air for long periods of time. Fecal-oral transmission is usually from contaminated food/water sources. And finally, vector borne transmission is carried by insects and other animals. (History of Epidemics and Plagues)