Amid COVID-19 outbreak that has brought the world's major economies to their knees, fear of another pandemic has created a panic in China after a suspected case of bubonic plague was reported on Sunday. 

Reports said authorities in the Chinese region of Inner Mongolia are on high alert after a suspected case of the plague was reported. The disease caused the `Black Death` pandemic over the centuries and is considered one of the deadliest pandemics in modern history. 

The case was discovered in the city of Bayannur, located northwest of Beijing, according to state-run Xinhua news agency.

Local authorities had issued a citywide Level 3 warning for plague prevention, the second-lowest in a four-level system. The warning will stay in place until the end of the year, according to Xinhua.

Plague, caused by bacteria and transmitted through flea bites and infected animals, is one of the deadliest bacterial infections in human history.

Plague is a zoonotic disease affecting rodents and transmitted by fleas from rodents to other animals and to humans. Direct person-to-person transmission does not occur except in the case of pneumonic plague, when respiratory droplets may transfer the infection from the patient to others in close contact, according to the World Health Organisation.

Plague occurs in three main clinical forms: 1- Bubonic plague, 2- Septicaemic plague and 3- Pneumonic plague

Bubonic plague is the form that usually results from the bite of infected fleas. Lymphadenitis develops in the drainage lymph nodes, with the regional lymph nodes most commonly affected. Swelling, pain and suppuration of the lymph nodes produces the characteristic plague buboes.

Bubonic plague, which is one of plague`s three forms, causes painful, swollen lymph nodes, as well as fever, chills and coughing. 

Plague is an infectious disease that affects rodents, certain other animals, and humans. It is caused by the Yersinia pestis bacteria. These bacteria are found in many areas of the world.

According to the US Center for Disease Control and Prevention, people most commonly acquire plague when they are bitten by a flea that is infected with the plague bacteria. People can also become infected from direct contact with infected tissues or fluids while handling an animal that is sick with or that has died from plague. People can become infected from inhaling respiratory droplets after close contact with cats and humans with pneumonic plague.

Human to human transmission of plague is possible but mostly in the case of pneumonic plague. When a person has plague pneumonia they may cough droplets containing the plague bacteria into air. If these bacteria-containing droplets are breathed in by another person they can cause pneumonic plague. Human-to-human transmission is rare and typically requires direct and close contact with the person with pneumonic plague.

Avoid any contact with live or dead rodents.

According to WHO, A vaccine effective against bubonic plague is available exclusively for individuals with a high occupational exposure to plague. However, it is not commercially available in most countries.

The most recent pandemic, also called “Third Pandemic,” erupted in 1855 in the Chinese province of Yunnan and traversed the globe over the next decades and by early 20th century had spread to all six inhabited continents. The disease spread to other regions from China with rats travelling on ships. By the time the pandemic ended in the 1950s, it had claimed at least 15 million lives with some estimates putting the number at 200 million. 

Just last week, two cases of bubonic plague were confirmed in Mongolia -- brothers who had both eaten marmot meat, according to Xinhua. Last year in May, a couple in Mongolia died from bubonic plague after eating the raw kidney of a marmot, thought to be a folk remedy for good health. Two more people got pneumonic plague -- another form of the disease, which infects the lungs -- months later across the border in Inner Mongolia.