A 10-year-old child from Colorado has died from causes related to the plague, a centuries' old disease once responsible for the death of more than half the world's population, according to local health officials.

The Colorado Department of Public Health and Environment confirmed the child’s death in LaPlata County, where it is investigating reports of the plague in animals and fleas from six counties.

According to the agency, a laboratory test confirmed the presence of the plague, which is also known as the bubonic plague or Black Death, and has taken the appropriate precautions. An investigation is ongoing.

“In Colorado, we expect to have fleas test positive for plague during the summer months,” Jennifer House, Deputy State Epidemiologist and Public Health Veterinarian for the Colorado Department of Public Health and Environment, warned in a statement.

“Awareness and precautions can help prevent the disease in people. While it’s rare for people to contract plague, we want to make sure everyone knows the symptoms. The disease is treatable if caught early,” she added.

Bubonic plague is caused by bacteria that can be transmitted to humans through infected fleas when bitten or having direct contact with infected animals such as rock squirrels, woodrats, prairie dogs, or other species of ground squirrels and chipmunks.

The bubonic plague is treatable in both people and pets if identified in time. Symptoms include the sudden onset of high fever, which can be accompanied by swollen lymph nodes.

Tens of millions of Europeans were killed by the plague in one of the worst pandemics in history in the 14th century, according to The Washington Post. The outbreak killed up to 60% of the population in an outbreak that reoccurred for 500 years, the news outlet said.

The health department advised against touching sick or dead animals and suggested staying out of areas where wild rodents live. The agency also said not to feed or handle wild rodents or squirrels.

House advised people to “Let a medical provider know if you think you have symptoms of plague or if you think you’ve been exposed.”

A New York man contracted an extremely rare and fatal brain disorder after eating squirrel brains. In the image: A squirrel forages for food in Baths Royal Victoria Park in Bath, England, Oct. 9, 2018. Matt Cardy/Getty Images