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The Plague

by Kris Dollard

Ring around the rosies, a pocket full of posies, ashes, ashes, we all fall down.

Is this a child’s song or echoes from the outbreak of Black Death, one of the deadliest epidemics in world history? Bubonic plague, a bacterial infection so named because it attacks the lymph system causing buboes (painful swelling of the nodes), is one form of this disease. Pneumonic plague is the same virulent bacteria in the lungs; it is highly contagious because it is transmissible through airborne particles.

The causative agent is the bacterium Yersinia pestis, which is found in the fleas of rodents. One bite from an infected flea can be enough to spread this disease. For the general public, steering clear of flea-infested rodents is both advisable and desirable. There have been cases of transmission from a cat or dog to a human, but this is highly unlikely if the animal is healthy, fairly flea-free and has not been out in the wild recently. The incubation period is 2 to 6 days from exposure.

Early symptoms may appear flu-like, such as shivering, vomiting, head aches and pain in the back and limbs. In addition, there will be intolerance to light, giddiness and possibly a white coating on the tongue. Later, there is painful swelling of lymph nodes, and a breaking of blood vessels leading to internal bleeding — as the blood dries under the skin it appears black (hence, Black Death).

Untreated, mortality can be up to 75%. A full regimen of antibiotics — Tetracycline for 10 days will Streptomycin for the first 5 days will almost always destroy the bacteria. The good news is that the patient is then immune for life.

During the three major outbreaks of plague, (which occurred in a period of about 16 years), 50 million people, about 20-30% of the world’s population, lost their lives. Despite the enormous human toll, the outbreak of plague actually led to a number of significant advancements for society. For instance, the widespread use of the printing press has long been linked to the need to disseminate disease-related information rapidly. Since there was a labor shortage on farms, landowners instituted wages for work, rather than a tenancy in the land. A governmental entity was formed to oversee public health during this period. Even an institution as established as the Roman Catholic Church lost members and influence as people turned to alternate methods to explain and eliminate this world-altering deadly disease.

Burrowing rodents and their fleas are by far the most prevalent carriers of plague. Rehabbers handling mice, rats and ground squirrels must pay special attention to flea control and be particularly sensitive to any unexplained deaths in their charges. Unfortunately, predatory mammals or scavengers who may eat this prey are also subject to infection. Those of us who deal primarily with these types of animals must also be vigilant about flea control.

Worldwide, there are about one to two thousand human cases of plague reported annually. Small epidemic outbreaks occur each year on the continents of Africa, Asia and/or South America, according to the World Health Organization. In the United States, human cases of plague average less than 18 per year, but according to the Centers for Disease Control (CDC), California is one of two regions where this can happen. Thankfully there was only one human case (Alameda County) in the San Francisco Bay Area between 1970 and 1997. In 1996 there was a small outbreak among animals in Santa Clara County (rural Gilroy), the first in 20 years. The victims were a bobcat, coyote and three wild pigs. No transmission to humans were ever found.

The CDC notes that four veterinarians and one assistant have confirmed domestic animal cases since 1959 as well as 20 human cases transmitted from pets. Sadly, one of the four vets (from Santa Clara County) died from the disease. Since most of us who do wildlife rehab also have pets, we would do well to be aware of the plague, no matter how incredibly remote the possibility of infection.

So back to our macabre little song; a “rosy” rash is the first symptom of plague; individuals often carried “a pocketful of posies” (herbs and spices) to sweeten the foul air; “ashes” refer to the cleansing bonfires and “all fall down” describes people dying off in droves. Given this information, will any of us ever feel the same about this childhood rhyme?

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