The bubonic plague is a horrible murderer that has affected mankind for millennia. It is the most well-known and universally recognized variant of the deadly infectious disease known as the plague and has manifested itself as recently as 2005. During the Middle Ages, the plague wiped out a third of Europe’s population and ravaged the ranks of Asia and the Middle East as well. It was called the Black Death.

Today, the World Health Organization (WHO) says the plague is still endemic in many places around the world, especially in Africa, the former Soviet Union, North and South America and Asia. WHO records show that 182 people died from the plague in 2003 (from a total of 2,118 reported cases) in mostly isolated cases that occurred in nine countries, with the lone exception being an outbreak in an Algerian village – the first such outbreak of the plague in 50 years – that affected 11 individuals and killed one. Two countries – Madagascar and the Democratic Republic of the Congo – accounted for 2,025 of the 2,118 cases and 177 of the 182 deaths in 2003. On an annul basis, the WHO estimates that these two countries routinely report an average of 600 to 800 cases each year. Countries such as Tanzania, Peru, the United States, China, Mongolia and Vietnam also reported cases of the plague in 2003.

According to published reports, the most recent outbreak of the plague happened in Zobia, north of the Democratic Republic of the Congo in December 2004, affecting workers in a diamond mine. The outbreak ended by mid-March 2005, with 130 people infected and 57 dead.

Medical research indicates that the plague can be attributed as a disease spread by rodents, such as marmots, black rats, prairie dogs, chipmunks, squirrels and other large rodents. Contrary to popular belief, it is not the rodents themselves that spread the disease, rather it is the so-called rat flea (Xenopsylla cheopis) that feeds upon infected rodents that spreads the disease. The bacteria multiply inside the rat flea, which soon becomes very hungry and begins to search frantically for a host. Once it finds a host, the rat flea bites at it vigorously but is unable to satisfy its hunger because bacteria has blocked the flea’s stomach, preventing the transmission of food or blood. Nonetheless, the flea keeps on feeding and soon vomits blood tainted with plague bacteria into the host’s bite wound. The plague then infects a new host (while the flea dies from starvation) and the infection has been passed along. This is how most humans get infected with bubonic plague.

It takes three to seven days after infection for the first symptoms of the bubonic plague to appear. Initial symptoms include chills, fever, diarrhea, headaches and the swelling of the infected lymph nodes. If untreated, 30–75%.of those afflicted with the plague will die.

There is a potent form of the plague known as septicemic plague which kills people on the same day that symptoms first appear. The symptoms of this deadly disease include bleeding of the skin and other organs, black patches on the skin as well as bite-like bumps that are commonly red and sometimes white in the center. Septicemic plague is fatal and, if untreated, kills 85-96% of those afflicted.

Pneumonic plague is another kind of plague that infects the lungs. This is perhaps the lone type of plague where person-to-person transmission of the disease is possible through respiratory droplets. Pneumonic plague usually takes two to four days to incubate but its symptoms can be detected in as little as a few hours after contamination. Initial symptoms include headaches, weakness and coughing with hemoptysis. Pneumonic plague, if untreated will kills 95% of those afflicted within one to six days.

The most recent known case of the bubonic plaque was reported by CNN News on April 19, 2006 in Los Angeles, California. It was the first reported case in that city since 1984.