O'FALLON, Mo. (AP) — A Missouri election judge who came to work despite testing positive for the coronavirus died in her sleep after a 15-hour shift at the polls, the director of her county’s election office said Friday.

The woman worked Election Day as an election judge supervisor at Memorial Hall in Blanchette Park in the St. Louis suburb of St. Charles. Officials don’t yet know if COVID-19 was the cause of death. County officials didn't release her name, citing privacy laws.

She tested positive on Oct. 30 but ignored advice to isolate and worked alongside nine other election judges. More than 1,800 people voted at the precinct. Judges were required to wear masks and were mostly behind a plastic glass barrier.

St. Charles County Election Authority Director Kurt Bahr said in a phone interview that the woman had previously worked several other elections, as had her sister at a different polling site. It was the sister who called Bahr’s office Wednesday to let him know of the woman’s death.

But Bahr said the sister didn’t know of the COVID-19 diagnosis.

“She was just as shocked," Bahr said. "The family was unaware she had tested positive. As far as I understand, the only person that knew was the spouse of the judge.”

Bahr said that as an election judge, the woman would have shown up around 5 a.m. to help prepare the polling place; worked the entire time the polls were open from 6 a.m. to 7 p.m.; then spent about an hour wrapping up.

She died in her sleep either late Tuesday or early Wednesday, Bahr said.

Another judge who worked at the Blanchette Park site called Bahr’s office to “try to figure out who it was” that had the illness, he said. “That judge more or less said nobody appeared sick. Nobody had symptoms.”

County health officials are urging the precinct's other judges to be tested for the virus, St. Charles County spokeswoman Mary Enger said. Contact tracing efforts have begun.

Bahr said the county is not recommending testing for those who voted at the precinct because their potential exposure was limited. He said most voters were inside for only 10-15 minutes and most of that time, they were alone filling out their ballots.

Bahr said the county had plenty of judges on standby Tuesday, so he wasn’t sure why the woman felt compelled to work. The job pays $175 for the day, but he suspected civic responsibility, not money, was her motivation.

Still, he wished she had made a different choice.

“Obviously it’s disheartening to find out that one, she passed, and two, that she knew she was sick and chose to work anyway,” Bahr said.

Some of those who cast ballots expressed similarly mixed feelings of anger and empathy. Catherine Eberle, 31, took her 4-year-old daughter and 5-month-old son with her to the polling place.

“I’ve just been trying to put myself in that person’s shoes in trying to understand what would make a person do that,” Eberle said.

Another voter, 57-year-old Annie Zimpfer, said there was a brief delay as she checked in, perhaps because she has sometimes gone by her first and middle names. A female supervisor was briefly called to the desk but remained separated by plastic glass.

“I’m hoping that nobody else will catch it from her actions,” Zimpfer said. “My anger has subsided a little bit, but I guess I just wish that people would realize, hey, we’re all in this together. Can we maybe help take care of each other?”

Eberle, a home health nurse, questioned why the poll workers weren't checked for a fever — a symptom of the virus. Missouri does not require workers to be tested or that they have their temperatures checked, said Nicholas Omland, spokesman for the Missouri secretary of state’s office.

But local authorities can implement precautions, something St. Charles County will consider for the next election in April, depending on the status of the virus, Bahr said. Right now, Missouri is seeing new record numbers of cases and hospitalizations almost daily.

“If the numbers are similar to what they are today, we’ll need an even more robust policy,” Bahr said. “I’m certainly willing to increase our precautions if COVID is not a distant memory by April.”