The Minnesota Department of Health is investigating a tuberculosis outbreak among eight people associated with Minnesota State University, Mankato.

State health officials are asking clinics to look out for tuberculosis symptoms in college-aged individuals who have spent time at the university since August 2016.

"Typically, health care providers seeing respiratory issues in an average, otherwise healthy 20-something Minnesotan wouldn't normally be thinking TB," Doug Schultz, a Health Department spokesman said late Thursday. Risk factors for the infection usually include travel abroad to a country where TB is common, but in this case, all but one contracted TB in the United States.

Investigators believe the bacteria originated with an international student and spread to at least seven others who had close contact with them, Schultz said. The majority of those affected are MSU students or former students.

The risk of it spreading to the general public is low, Schultz said.

To contain the outbreak, health officials contacted about 700 people who may have interacted with the patients, such as roommates and significant others. Of those, they identified another 30 individuals who have a latent form of TB, meaning they tested positive for the bacteria but didn't exhibit symptoms.

TB is caused by a bacterial infection and is curable if treated. It usually affects the lungs, though the bones, spine or other organs can also be infected.

Minnesota clinics typically see around 140 TB cases each year, but an outbreak this size is considered unusual.

Though many think TB was eradicated years ago, about 10,000 Americans are diagnosed annually with it, according to the Centers for Disease Control and Prevention. Formerly known as consumption, the disease was greatly mitigated by the 1950s due to advances in antibiotics.

In 2017, more than 70 percent of those diagnosed were born outside the United States, including in Africa and Asia, where the disease is common. The percentage of foreign-born TB patients in Minnesota is over 80 percent, experts said.

That year, an outbreak of drug-resistant TB in Ramsey County infected 17 people, killing three of them.

It isn't likely to be spread during brief contact. Those with extended periods of exposure are most susceptible.

Anyone who develops associated symptoms — persistent coughing, weight loss, chest pain and fatigue — should seek immediate medical attention and contact Blue Earth County health officials.

Liz Sawyer • 612-673-4648