By Louisa Moller

BOSTON (CBS) – Several Massachusetts districts have been plagued with staff shortages due to the highly contagious Omicron variant.

More than 1,000 teachers and staff members were out Tuesday across Boston. Superintendent of Schools Dr. Brenda Cassellius said there were 461 classroom teachers and 52 bus drivers among the 1,000 sick calls. Not all of the absences are COVID-19 related.

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Cassellius said 42 schools in the city were dealing with 20% of their staff members being out with 60 central office staff members working to fill in the gaps.

In Lawrence, both high school and pre-kindergarten instruction were cancelled Tuesday. Officials said the district had 274 staff members out, 177 sick calls related to COVID.

Brockton also abruptly closed its high school for the day with 44 staff members ill just within the high school.

“I think there are several districts where there are schools that are sort of teetering very closely to how can we do this?” said Tom Scott, the Executive Director of the Massachusetts Association of Superintendents.

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Scott said that many districts are busy plugging staff holes with staff who do not normally teach in the classroom.

“This may come in the form of a teaching assistant, may come in the form of a director of a curriculum area. May come in the form of assistant principal or a principal,” Scott said.

Some experts continue to emphasize that in-person learning, even the kind disrupted by the Omicron variant, is far better than remote learning for children.

Joseph Allen, a public health expert and professor at the Harvard T.H. Chan School of Public Health, says strong evidence from earlier in the pandemic supports the need to keep kids in classrooms.

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“We see drops in math scores, we see drops in reading scores. We see kids missing from the system entirely,” Allen said.

Louisa Moller