Another two people have tested positive for COVID-19 at St. Martin Catholic Elementary in Smithville.
But Niagara Catholic says they're not linked to the outbreak that was declared on Thursday.
Both of the newly infected individuals are self-isolating and contact tracing is underway.
Public Health says there was no risk of exposure for one of the cases.
The principal has sent a letter to all staff and students to notify them of the situation.
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