“A fast-moving outbreak of a highly-contagious virus has sickened hundreds in Colorado, prompting officials to take the unprecedented step of closing an entire school district of about 22,000 students.

“There’s an all-out effort to eradicate a microscopic enemy, as crews sanitized hallways and scrubbed down classrooms at Mesa County schools.

“Hundreds of students and teachers have fallen ill with symptoms of the highly-contagious norovirus, including Cendie Wood’s grandchildren.

“”Every time I send the kids back to school they come home sick,” Wood said.

“The outbreak apparently started last week with siblings who attend schools in the district. The contagion and a second strain then quickly spread from school to school, forcing officials to take the unusual step and close all 46 schools.”

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