A city in North China has been put on alert after one case of the Bubonic plague was confirmed.

According to The Global Times, local authorities in Byannur — a city from the autonomous region of Inner Mongolia — have implemented strict epidemic control and prevention measures.

The patient — a local farmer — has been isolated in a local hospital and is in stable condition.

His case was followed by another suspected infection of a 15-year-old patient who developed a fever after coming into contact with a marmot hunted by a dog.

#Mongolia discovered another suspected patient infected with the bubonic plague. The 15-year-old patient had a fever after being in contact with a marmot hunted by a dog, according to Mongolian health authorities on Monday. pic.twitter.com/JJ2sEH9uoB

— Global Times (@globaltimesnews) July 6, 2020

Alert Level Three

The Global Times reported that under the Level Three alert that has taken effect in Byannur, local residents are required to strictly follow prevention and control measures including not hunting illegally and eating or carrying animals and their products out of the area.

Residents are also expected to report ill or dead animals, people showing signs of a fever, and sudden deaths.

Authorities expect the alert to stay in place for the rest of the year.

Once the world's most feared disease

According to the BBC, the Bubonic Plague — which is caused by bacterial infections — was once the world's most feared disease.

It was responsible for some of history's deadliest epidemics such as the Black Death, which killed about 50 million people across Africa, Asia and Europe in the 14th Century.

However, nowadays it can be easily treated by antibiotics.

Left untreated, the Bubonic Plague kills between 30 to 60 per cent of those infected, reported the BBC.

Symptoms of the plague include high fever, chills, nausea, weakness and swollen lymph nodes in the neck, armpit or groin.

Two people in the country of Mongolia died from the disease last year.

They had contracted after eating the raw meat of a marmot - the same type of rodent the second suspected case in Inner Mongolia came into contact with.

Top image from Sergio Tittarini via Flickr