Earlier this month two other cases of bubonic plague were registered in Khovd province. More than 140 people were tested, but no other cases were found.
A herdsman also contracted the plague in China’s northern Inner Mongolia region, prompting local authorities to ban the hunting and eating of animals that could carry the plague until the end of the year.
At least one person dies of the plague every year in Mongolia despite government campaigns to discourage people from eating marmot or approaching the animal.
But many in rural areas grow up learning to hunt and eat the large ground quirrel, and some believe eating its innards is good for health.
An ethnic Kazakh couple died of the plague last year after eating raw marmot kidney.
The recent cases prompted Russia’s eastern Siberian region of Burytia to test rodents for the bubonic plague and urge residents not to hunt or eat marmot.
It also comes as Mongolia’s borders remain closed due to the coronavirus pandemic.