MITCHELL, S.D. (AP) — The South Dakota Department of Health says a 19-year-old Dakota Wesleyan student found dead in a dorm last week died of a rare infection.

The department said Saturday that Beau Keeter of Miller died from meningococcal disease.

In a statement, Dr. Lon Kightlinger, state epidemiologist for the health department, says department disease prevention staffers are contacting people who may have been exposed to offer them antibiotics.

Kightlinger calls the disease "a serious illness" but says vaccinations are necessary only for those who have had close contact, such as sharing a water bottle.

The Argus Leader reports the state has reported nine cases of meningococcal infection in the past five years.

Keeter was a freshman athletic training student and a member of the basketball team. His roommate found his body in Dayton Hall on Wednesday.

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