Authorities in China have issued a warning after a suspected bubonic plague case was reported in the Inner Mongolia Autonomous Region.

Residents in the Bayannur district have been ordered not to hunt and eat wild animals after a herdsman was confirmed to have caught the disease on Sunday.

Another patient, a 15-year-old boy, was also suspected to be infected on Monday after developing a fever following contact with a marmot hunted by a dog, according to Global Times.

Health officials of the city of Bayan Nur have placed a third-level alert until the end of the year and asked the public to report any sick or dead marmots.

“At present, there is a risk of a human plague epidemic spreading in this city. The public should improve its self-protection awareness and ability, and report abnormal health conditions promptly,” said a local health authority, as quoted by the China Daily newspaper.

Bubonic plague is a bacterial infection commonly spread through fleas from small animals. It was the cause of the Black Death pandemic that killed an estimated 50 million people across Asia, Europe and Africa in the 14th century.

The disease can now be treated with a number of antibiotics, such as gentamicin and doxycycline.

Symptoms of the plague include high fever, headaches, nausea and swollen lymph nodes.

While plague outbreaks have become increasingly rare in China, occasional cases are still reported. According to Reuters, China reported 26 cases and 11 deaths from 2009 to 2018.

This article originally appeared on Over60.