An outbreak of sexually transmitted disease is hitting the Milwaukee area, and an alarming percentage of the patients are teenagers.

According to The Journal Sentinel, at least 125 people -- including some high school students -- have contracted HIV, syphilis or both in one of the largest sexually transmitted infection “clusters” discovered in the city.

Less than 10 percent of the 125 people who tested positive are Milwaukee Public Schools students, but health care experts anticipate the number of cases could go up.

“This is an epidemic people are not talking about enough, and it leads to people taking unnecessary risks,” said Melissa Ugland, a public health consultant told the newspaper.

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The Centers for Disease Control and Prevention defines a "cluster" as “an unusual aggregation, of disease that are grouped together in time and place." Ugland told the newspaper this cluster was identified because patients could all be connected, and were in contact with each other during a 12-month period.

Most of those who were tested in the group were men and 45 percent were HIV positive, according to Ugland and other health care advocates. Information about which school or schools are affected by the cluster has not been released.

Even more concerning, health officials confirmed in a tweet that three local babies were also born with syphilis. "Troubling public health news, there has been an increase in new cases of HIV/Syphilis," the Milwaukee Health Department tweeted. "Sadly this included infants in 2017, " the message read.

The Milwaukee Health Department released a statement that the entire city is experiencing an increase in sexually transmitted infections in young people ages 15 to 24.

The statement read, "Because schools have a significant number of students in the 15-18 age group, we are working with the Milwaukee Health Department, in a collaborative and preventive effort, to share information with young people in middle schools and high schools to keep them healthy and to protect their health."

Ugland told the newspaper that the number of those affected may grow.

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“(The cluster) was still considered ongoing; they were continuing to try to track down some folks,” Ugland explained.

The former health commissioner Bevan Baker reportedly met with Mayor Tom Barrett to brief him about the cluster in December and again in early January. The meeting was a week before Baker resigned over troubles with Milwaukee's lead-poisoning prevention programs.

In an effort to create public awareness, and prevent further spread of disease, the Milwaukee Health Department is launching a campaign on the city's public transit system to inform riders about sexually transmitted diseases.