THE SECOND PLAGUE PANDEMIC – BLACK DEATH(1347 – 1351) – Occurrence and Curtailment [ part 2]

This is the second episode on the plague pandemic.

Mechanism of transmission –

The mechanism of transmission of the bacteria from the flea to a host was established by Paul-Louis Simond.

Causative organism of Plague – Yersinia pestis (bacteria)

Vector – Rat flea – Xenopsylla cheopis (shown in the picture above)

Natural Reservoir – Rodents

Accidental Host - Man

Plague bacteria circulates in low concentrations among certain rodent populations keeping the disease enzootic. Occasionally, the disease may spread to other species causing an outbreak this is then called epizootic disease. Following an epizootic outbreak, man becomes susceptible to the disease.

Modes of transmission –

1. Flea bites – by a flea which is infected by Yersinia pestis. The bacterium multiplies in the midgut of the flea thereby obstructing it. This causes the flea to be starved leading to aggressive feeding behavior of the flea. As it feeds, the flea regurgitates these bacteria into the host causing the host to be infected. This mechanism leads to bubonic plague or septicemic plague.

2. Contact with contaminated fluid or tissue – Lack of precaution when handling infected animals may lead to bubonic plague or septicemic plague.

3. Droplet infection – The pneumonic type of plague causes the infected person to produce cough droplets which release the plague bacteria into the atmosphere. This requires a person to breathe in the droplets to be infected thereby by necessitating direct and close contact as a means of spread.

The different types of plague and the symptoms experienced –

Bubonic Plague: Patients develop sudden onset of fever, headache, chills, and weakness. One or more lymph nodes may be swollen, painful and tender; these are called buboes. They are usually seen in the armpits or groin or the neck. Black death was mainly bubonic type of plague. Pneumonic Plague: Affected individuals develop fever, headache, weakness, and a rapidly developing pneumonia with shortness of breath, chest pain, cough, and coughing up of bloody sputum. If left untreated, it can rapidly progress to multiple organ failure, adult respiratory distress syndrome and ultimately death.

Septicemic Plague: It is characterized by fever, chills, extreme weakness, abdominal pain, shock. Bleeding into the skin and other organs may be seen. The skin and other tissues may turn black and die, particularly on the fingers, toes, and the nose.

What is the treatment for Plague?

1st picture (on the left)– shows the lancing of a bubo

2nd picture – shows the plague doctor in full gear

A variety of questionable cures were used for the treatment of Plague back in the 14th century ranging from bloodletting, to flagellants, who whipped themselves as they moved from town to town. In 1630, the Plague doctors had specific outfits which were characteristic of them. The Plague doctor had a special outfit – a cloak to protect him from contacting any infectious surface, a mask with glass eye openings and beak shaped nose, stuffed with herbs and spices to protect the doctor from miasma. A wand which helps him to direct patients. A plague doctor was specifically hired by the city officials to take care of patients as well as to maintain the record of deaths.

Presently, modern day antibiotics can effectively combat against the disease.

How did the Plague lead to such devastation in its wake –

The probable explanation could be that the Great Famine which affected Europe prior to the Black death led to a population of malnourished individuals with weakened immune systems making them more susceptible to the deleterious consequences of the disease.

The other possible rationale could be the poor hygienic conditions at that time – lack of sanitation, clean drinking water and basic hygiene play a vital role in the spread of the disease.

The most reasonable one is the lack of scientific advancement. Today, if plague is under control, it is due to the early diagnosis and treatment with antibiotics. The mid-1300s was the pre-antibiotic era, which was flooded with religious superstitions and unsophisticated medical practices which could have dragged the death toll further.

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References-

1. https://en.wikipedia.org/wiki/Black_Death

2. https://www.cdc.gov/plague/index.html?CDC_AA_refVal=https%3A%2F%2Fwww.cdc.gov%2Fplague%2Fhistory%2Findex.html

3. https://en.wikipedia.org/wiki/Plague_doctor

4. https://rarediseases.org/rare-diseases/plague/

5. https://www.britannica.com/event/Black-Death

6. Park’s Textbook of Preventive and Social Medicine by K. Park – Page no. 101

Image Credits-

1. https://www.npr.org/sections/goatsandsoda/2017/08/18/542435991/those-iconic-images-of-the-plague-thats-not-the-plague?utm_source=facebook.com&utm_medium=social&utm_campaign=npr&utm_term=nprnews&utm_content=20170818?utm_source=facebook.com&utm_medium=social&utm_campaign=npr&utm_term=nprnews&utm_content=20170818

2. https://en.wikipedia.org/wiki/Oriental_rat_flea

3. All the other images were taken from Pinterest. All the image credits belong to the rightful owners.