Bubonic Plague - Lecture Notes

Overview

• Bubonic plague is a type of plague caused by the bacterium Yersinia pestis.
• Symptoms appear 1 to 7 days after exposure, including fever, headaches, vomiting, and swollen lymph nodes (buboes).
• It primarily spreads through infected fleas from small animals.
• Other forms include septicemic and pneumonic plague.

Symptoms and Complications

• Initial symptoms are flu-like: fever, headaches, vomiting, and swollen lymph nodes.
• Acral necrosis (skin discoloration) and buboes (swollen lymph nodes that may burst) are common.
• Complications can include gangrene and meningitis.
• Without treatment, fatality rates are 30-90%; with treatment, 10%.

Transmission

• Transmitted mainly by fleas from animals like rabbits, hares, and some cats.
• Can also spread through contact with body fluids from infected animals.
• Bacteria enter through skin via flea bites, travel to lymph nodes.

Diagnosis

• Diagnosis involves identifying Y. pestis in blood, sputum, or lymph node fluid.
• Quick screening with rapid dipstick tests available.

Prevention

• Preventive measures include avoiding handling of dead animals and controlling rat populations.
• Vaccines exist but are recommended only for high-risk groups.
• Effective antibiotics include streptomycin, gentamicin, and doxycycline.

Historical Context

• Considered the likely cause of the Black Death in the 14th century.
• Also linked to the Plague of Justinian and the third pandemic.
• The Black Death significantly affected European economic development, increasing wages due to labor shortages.

Epidemiology

• Between 2010 and 2015, 3,248 cases documented with 584 deaths globally.
• Countries with most cases: Democratic Republic of the Congo, Madagascar, Peru.
• Recent outbreaks in Madagascar (2017) and China (2020).

Biological Warfare

• Used as a weapon in historical conflicts, including during the siege of Caffa and the Second Sino-Japanese War.

Modern Research

• DNA analysis traces the bacterium back to the Late Bronze Age.
• Research indicates pandemics were interconnected, with the bacterium persisting in rodent populations between outbreaks.

Cultural and Literary Impact

• The plague has influenced numerous historical and fictional accounts, such as Boccaccio's "The Decameron."
• Used as a backdrop in literature and film to explore societal and existential themes.

Conclusion

• Bubonic plague remains a critical area of study in historical and modern contexts due to its impact on society and potential for future outbreaks.