PRINCETON — A Mercer County school was given several thorough scrubbings since last week, amid a spike in students home sick with the flu.

Nearly 20 percent of the more than 700 students at J. Witherspoon Middle School still were absent as of Monday, according to Princeton School Superintendent Steve Cochrane.

He said in an email that the number was down slightly since late last week and appeared to be "moving in a positive direction."

The school's custodial staff has been using hospital-grade disinfectant to wipe down common surfaces such as handrails, door knobs, bathroom fixtures and keyboards, in a protocol that began late last Thursday.

Families within the district have been urged to keep children home with flu-like symptoms, such as sore throat, fatigue and muscle aches. It also has been strongly advised that students remain out of school until they are fever-free for at least 24 hours.

For the ongoing 2018-2019 flu season, there has been 21 severe cases of pediatric flu. There has been one pediatric flu death, reported the last week of December.

The most recent weekly flu activity report for NJ, which ended on February 2, showed high flu activity across the entire state.

Over the same span, New Jersey was among 24 states reporting high flu-like activity to the CDC.

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