In the middle ages preceding the scientific understanding of microbes and the discovery of antibiotics, the Bubonic Plague or the Black Death ravaged Europe infecting the masses. The plague was transmitted to humans from by fleas who had fed on rodents carrying the bacteria that causes the Bubonic Plague. Due to close quarters, high populations of rats, and lack of basic hygienic practice, the Bubonic Plague spread like wildfire and claimed the lives of nearly half the population of Europe. Though we now have antibiotics and protocols for managing the spread of infectious diseases, there are still a few areas of the world facing the Bubonic Plague today.
There are three types of plague, septicemic, pneumonic, and the most common variety, Bubonic Plague. The cause of Bubonic plague is the bacteria Yersinia pestis pictured from an electron microscope in the Featured Image. Y.pestis is a bacillus shaped, gram negative bacteria that is very well suited to multiply within the lymphatic system of the human body. This is due to “virulence factors” or characteristics such as it’s ability to irreversibly bind to cells allows it to invade cells easily and reproduce. This bacteria is transmitted to humans through the flea bite or by touching the tissues of a dead animal infected with the bacteria.
According to the World Health Organization the diagnosis of Plague requires lab testing of the pus of an infected lymph node and is treated with common antibiotics. If any symptoms of plague are present medical care should be sought out immediately, though treatable Plague is extremely serious and must be diagnosed early to properly treat. The Center for Disease Control ( CDC) lists the major symptoms as fever, headache, chills, and swollen lymph nodes “The bacteria multiply in the lymph node closest to where the bacteria entered the human body.”. Pictured below is the lymph node becoming full of Y. pestis growth.
While most are aware of the Black Death that swept across Europe there are still cases today of Plague, especially in certain developing countries. There are still multiple cases of Bubonic Plague in the United States itself every year as shown in the graph below.
Plague is currently more common and has had more recent outbreaks in the African continent, specifically Madagascar most recently. Antibiotics such as Doxycycline, Streptomycin, or Ciprofloxacin can be effectively used to treat Plague but alas, prevention is the best medicine. Be aware of any recent outbreaks especially while traveling to an area that has recently had Plague activity and avoiding touching infected persons or dead animals will keep the risk of contracting Bubonic Plague very low.
References
“Plague” ;umn.edu; http://www.cidrap.umn.edu/infectious-disease-topics/plague
“Plague”; who.int; https://www.who.int/csr/disease/plague/en/
“Plague”; cdc.gov; https://www.cdc.gov/plague/index.html
“Plague” ; mayoclinic.org; https://www.mayoclinic.org/diseases-conditions/plague/symptoms-causes/syc-20351291
Third Cat in Wyoming Diagnosed with Plague: Here’s Why You Shouldn’t Panic
This article mentions the discovery of Yersinia pestis , which is the cause of bubonic plague, in a domestic outdoor cat. The author emphasizes that this bacteria is naturally found in many animals and exists all over the world and therefore, should not cause widespread alarm. It is also mentioned that though there are still cases of bubonic plague in humans in the United States each year, the infection is cured by antibiotics when treated in a timely manner.
Why We Haven’t Eradicated the Plague
This article contains information from new research that may disprove the original theory that white blood cells carry bubonic plague bacteria to the lymph nodes causing infection. The research shows that helpful white blood cells called phagocytes readily consume and destroy Yersinia pestis meaning that it is not carrying it back to the lymph nodes. Through experiments with mice the researchers found that most of the bacteria transferred from flea bites ends up stuck in the skin and that only a few of the bacteria actually reach the lymph nodes. The time it takes for these few bacteria to reach is far too fast for phagocytes to be carrying it, and it is hoped that using this knowledge there may be a way to ensure that the bacteria never reach the lymph nodes.
After the Black Death, Europe’s Economy Surged
This article discusses the European economy before and after the bubonic plague killed masses of the population. It states that before the Black Death Europe was overpopulated and large parts of the population were starving due to agricultural limitations. Then after the mass of the plague outbreaks so many had died that there were so few people working and producing that the economy fell into recession. Finally 100 years later the economy boomed as technology and information grew immensely due to the fact that the economy wasn’t so focused on producing enough food to feed it’s high population.