ST. LOUIS COUNTY, Mo. — The St. Louis County executive issued a warning to the family of a woman who is the first “presumptive positive” case of coronavirus in Missouri: keep yourselves quarantined or we will get a court order to make you.

St. Louis County Executive Sam Page said the family of the woman were in contact with state and county health officials starting on Thursday when the woman — who eventually tested positive — self-reported her symptoms. In the days since, the family has been in contact with those same officials multiple times a day and it was made clear that they were expected to self-quarantine in their home in Ladue.

Despite this request, Page said the father decided to take his other daughter to a father-daughter dance Saturday night. Villa Duchesne confirmed the father and daughter were at the dance, which was held at the Ritz-Carlton Hotel in Clayton but left as soon as they were informed the daughter had tested positive.

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Page said the woman who tested positive “conducted herself responsibly and maturely “by following the health department’s directions. The father, on the other hand, did not, Page said.

“The way this family had reacted to this situation is really the tale of two reactions, and a study of how people should and should not react to the coronavirus,” Page said.

Page said they found out about the break of quarantine Sunday morning.

The news is less than a day after Missouri Gov. Mike Parson announced that the woman in her 20s — who recently traveled to Italy — was the state’s first case of coronavirus.

Her test results are being called "presumptive positive" because the test she was given was not FDA approved, but the results are being treated as a positive result. It was processed at a health lab in Missouri. Last month, the state health department received federal approval to run tests in its own health lab.

Page said the family would need to remain self-quarantined inside their home, and if they do not, the county would get a court order to force them to remain in their home.

“We can go to court and get a court order that will require them to remain in their house by order of a sheriff,” Page said.

The other family members have not shown symptoms, and because there is no reliable test for people without symptoms, they have not been tested, Page said.

Villa Duchesne announced it would not hold classes Monday.

St. Louis County residents with questions about what they should do can visit the county's coronavirus website or call their hotline at 314-615-2660, Page said.