WESTWOOD (CBS) – A Westwood Public Schools employee who was working with students over the summer has tested positive for COVID-19, after initially being told her test was negative.

The district opened Downey Elementary School and Westwood High School for in-person instruction during the district’s Extended School Year special education program. About 100 students participate in the program.

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According to Superintendent Emily J. Parks, the staff member started to feel ill on July 3, was tested for COVID-19 and stayed home while waiting for test results. The staff member was told that her test results were negative, and since she was feeling better, she returned to work Monday, July 13. While at school, she received a phone call saying that there had been a mistake, and she had, in fact, tested positive for COVID-19. The staff member immediately went home.

“We share the community’s concern that a staff member in our summer program has tested positive for coronavirus. We want to emphasize that her exposure to students was limited to a three-hour block, during which time she was properly outfitted with PPE,” Parks said in a statement.

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Parents and students in close contact with the staff member have been notified, and the Downey School was closed for cleaning.

“It’s fragile under the very best of conditions,” said Max Page, Vice President of the Massachusetts Teachers Association. He believes rushing back to school could be dangerous for kids and teachers. The union is calling for a phased education reopening.

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“This case in Westwood, it sounds like this one case was handled quite well. But you imagine when a million public school students, our 117,000 members return… that’s what really worries us.”