As a Chinese city sounds alert on the bubonic plague, this is all you need to know about the deadly disease that has killed tens of millions of people through the course of history. 

What is going on? 

In July 2020, two cases of bubonic plague were confirmed in Bayannur in Mongolia. The patients are two brothers who reportedly ate marmot (a rodent species). 

Since, the 1,466 people who came into contact with the pair have been identified and quarantined. 

Officials have also issued a Level Three alert, the second-lowest in a four-level system. The change also forbids the hunting and eating of animals that could carry the plague, in this case, marmots.  

How common is the plague?  

There were four cases reported in Mongolia in November 2019, and of these, two were of pneumonic plague, a deadlier variant.  

However, outbreaks are considered rare. Between 209 and 2018, China reported 26 cases and 11 deaths.  

What is the Bubonic Plague? 

‘Bubonic’ derived from the Greek word “βουβων” meaning ‘groin’.  

The term ‘buboes’ is also used to refer to the swollen lymph nodes. The bubonic plague is one of the three forms of plagues caused by Bacterium Yersinia pestis.  

Read also: Five of the Biggest Pandemics in History 

How does it spread? 

The plague is often transmitted by infected fleas, but humans can also get infected through direct contact with infected animals like rodents, squirrels and hares.  

Incubation period: 

A person usually becomes ill with bubonic plague 2-6 days after being infected. Someone exposed to Yersinia pestis through the air would become ill within 1-3 days. 


Most common symptoms are of that of the flu such as a sudden onset of fever, chills, aches, weakness, vomiting and nausea. Exposure can also cause swollen and painful lymph nodes where the bacteria entered the body.  

Can people still die from the plague?  

There is currently no effective vaccine against the plague, but it is treatable with antibiotics. The plague is a very serious illness, if left untreated, it can be fatal.  

The three major Bubonic plague outbreaks 

The Justinian Plague (541 CE) 

The Justinian Plague started in central Africa and spread to Egypt and the Mediterranean. It killed an estimated 30 to 50 million people. 

The Black Death (1347) 

Originating in Asia, the Black Death plague spread to Crimea, then Europe and Russia. It killed approximately 200 million people. 

The Third Pandemic (1894) 

Starting in Yunnan, China, the plague reach Hong Kong and India, and then the rest of the world. Reports say its death toll was more than 10 million in India alone.  

Zahra Khozema