The bubonic plague, also known as the Black Death was previously the world’s most feared disease, but today is easily treated with modern antibiotics.

On Sunday, China issued a citywide Level 3 warning for plague prevention and closed tourist spots in the northern Inner Mongolia region after reports of bubonic plague cases.

The Chinese news agency Xinhua and Russian state media agency TASS reported last week that two brothers who had eaten marmot meat in Khovd province contracted the disease.

On the weekend, Chinese authorities confirmed that a shepherd who is in stable condition at a local hospital, tested positive.

The World Health Organization (WHO) says, it is carefully monitoring the situation, and WHO Mongolia representative, Sergei Diorditsu, reportedly said the province sees seasonal outbreaks of the plague.

The bubonic plague, also known as the Black Death, Pestilence and the Great Mortality, was previously the world’s most feared disease, but today is easily treated with modern antibiotics.  If the infection is left untreated, the fatality rate is between 30-60 per cent.

Yearly between 1,000 – 2,000 cases are reported, according to the WHO, but the numbers do not consider unreported cases.

Bubonic Plague Symptoms

According to the Centres for Disease Control and Prevention (CDC), patients develop sudden onset of fever, headache, chills, and weakness and one or more swollen, tender and painful lymph nodes (called buboes). 

The Bubonic Plague

The bubonic plague attacks the lymphatic system with a bacteria called Yersinia pestis (Y. pestis). The plague is transferred to humans by bites or scratches from infected fleas or animal. Or by eating the meat of animals infected with the bacteria.

The plague is responsible for one of the most fatal epidemics recorded in human history, which in the 14th Century resulted in the deaths of over 50 million people across North Africa, Asia and Europe.

During the Great Plague of 1665, it killed about a fifth of London’s population during, according to the BBC.

“Unlike in the 14th century, we now have an understanding of how this disease is transmitted,” Dr. Shanthi Kappagoda, an infectious disease physician at Stanford Health Care, told Healthline. “We know how to prevent it — avoid handling sick or dead animals in areas where there is transmission,… We are also able to treat patients who are infected with effective antibiotics, and can give antibiotics to people who may have been exposed to the bacteria [and] prevent them [from] getting sick,” she said.