First responders were called to the Lehigh Valley Children’s Center on Park Avenue in Neffs around 10:30 a.m., troopers said.
In total, five adults and eight infants and toddlers were taken to Lehigh Valley Hospital Cedar Crest.
Police say it's still unclear what caused the victims to feel sick. The day care will remain closed for the rest of the week while air quality specialists work the building, they added.
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