The first reported death tied to vaping in the United States was confirmed on Friday by officials from the Illinois Department of Public Health. The patient, whose name, age, sex and hometown have not yet been released, but the death appears to be the first among an outbreak of lung illnesses now under investigation, by state and federal health officials, in connection to vaping. 193 people have been struck with similar symptoms between June 28th to now, according to the U.S. Center for Disease Control and Prevention.

In Illinois, the people who are being hospitalized are between the ages of 17 and 38. The affected individuals have had symptoms of coughing, shortness of breath, and fatigue, according to the CDC. Some also experienced vomiting and diarrhea. Symptoms worsened over a period of days or weeks before they were hospitalized.

While some of the cases appear to be similar, officials said they are unsure of whether or not the illnesses are associated with the e-cigarette devices themselves, or with specific ingredients that are inhaled through them. Health officials have said patients have described vaping a variety of substances, including nicotine, marijuana-based products and do-it-yourself “home brews.”

Officials also said on Friday that they don’t know why the surge of illnesses is becoming an outbreak now, because various forms of the battery-powered e-cigarette devices have existed for years. Brian King, deputy director for research translation for the CDC’s Office on Smoking and Health, said cases could have been occurring previously, “but we weren’t necessarily capturing them.”

Mitch Zeller, head of the Center for Tobacco Products at the Food and Drug Administration, said the agency is working to identify the products used, where they were purchased, how they were used and whether other compounds were added.

In a statement, the Centers for Disease Control said it is working with state and local health departments and the FDA to learn more about the death and the “ongoing outbreak” of a pulmonary disease related to use of e-cigarettes.