Humans Are Bad At Risk Assessment

On May 19, one teacher, who was not vaccinated against the coronavirus, began feeling fatigued and had some nasal congestion. She dismissed it as allergies and powered through. While she was usually masked, she made an exception for story time so she could read to the class.

By the time she learned she was positive for the coronavirus two days later, half her class of 24 had been infected — nearly all of them in the two rows closest to her desk — and the outbreak had spread to other classes, siblings and parents, including some who were fully vaccinated.