Disease control experts say this is not the case—in fact, they have begun to see a re-emergence of the disease. The first such outbreak took place in 1994 in India, which killed 56 people and hospitalized more than 600. Since then, the plague has been positively identified in the Democratic Republic of Congo (65 deaths in 2005), Madagascar (69 deaths in 2014 and 57 more in 2017), and even parts of the United States (four deaths and 16 infections in 2015). As late as June 2017, two New Mexico natives were positively diagnosed with the plague, adding to the 600-plus infections expected globally by the year’s end.

Bubonic Plague Symptoms

When a human is infected with the bacteria called Y. pestis, it travels through the lymphatic system and ends up in the lymph nodes where it causes painful, boil-like enlargements called buboes. This typically happens within one to seven days of exposure and can be accompanied by a number of symptoms including:

Chills High fever Extreme exhaustion Pain Breathing constriction Muscle cramps Vomiting of blood Gangrene of the toes, fingers, lips, and nose Opening of swollen buboes (lymph nodes in armpit or groin) Seizures

Without treatment, the bubonic plague will result in death in 60 percent to 90 percent of cases, usually within 10 days. With treatment, about 90% of patients survive.

Other Forms

The route of the disease can vary in persons infected by Y. pestis. For instance, rather than traveling from an insect bite to the lymph nodes, the bacteria can enter the body through other routes and cause an entirely different set of symptoms.

Pneumonic plague occurs when the bacteria is spread to the lungs, usually when an infected person coughs or sneezes on another. While uncommon, it is considered a more serious form of plague, causing the rapid development of pneumonia, chest pains, and bloody or watery sputum, If left untreated, pneumonic plague can cause respiratory failure and death, usually within 36 hours. Septicemic plague occurs when the bacteria find its way directly into the bloodstream, often through a crack or sore in the skin. It is the rarest form of the disease and arguably the most aggressive. Symptoms are similar to that of the bubonic plague but can include characteristic bleeding beneath the skin. Death is almost inevitable if treatment is not delivered within 24 hours.

Causes

Bubonic plague is a potentially fatal infection caused by the bacteria Yersinia pestis.

Since the bacteria is harmless to fleas, it has the perfect vehicle by which to be carried directly from animals to humans. In addition to smaller rodents like chipmunks and prairie dogs, Yersinia pestis has been found in larger mammals including rabbits, opossum, wild coyotes, and even domestic dogs and cat that have come into contact with rodents.

Diagnosis

Bubonic plague is diagnosed by running lab cultures on sputum, blood, spinal fluid, or infected lymph nodes. In parts of the world where the plague is more commonly seen, a rapid dipstick test can usually identify bacterial antigens within 15 minutes.

Treatment

Due to the clinical severity of the disease, doctors will usually start treatment presumptively while awaiting lab results. Ideally, treatment should be started within 24 hours, usually in the form of intravenous antibiotics such as streptomycin, doxycycline, or tetracycline. If treated in a timely manner, survival rates can range from 85 percent to as high as 99 percent.

Prevention

The key to the prevention of bubonic plague is the avoidance of rodents or any wild animal that can carry fleas. It also requires you to safeguard your property from things that attract animals, like open waste containers or unfenced gardens. There are precautions to take for the prevention of bubonic plague, especially if you live in an area where flea infestations are common.

If traveling to parts of the world where outbreaks have occurred (Madagascar, Peru, Democratic Republic of Congo), check travel advisories before departure and bring plenty of insect repellent containing 80 percent DEET. There is currently no vaccine to prevent bubonic plague.

While rare, it is important to take precautions to prevent this or any other flea-borne disease, whether it be typhus, tapeworm, or Lyme disease. 

A Word From Verywell

The bubonic plague is commonly associated with the Black Death of the 14th century, but there are many recent cases of the disease on record. It is important to remember, especially if you live in areas with high flea infestations, to take the proper precautions to prevent the disease. Though fatal, the bubonic plague is now very treatable, especially if it is caught early on.

Diagnosis.