Niagara Catholic is confirming an outbreak at one school and cases at three more.
The outbreak was declared at St. Andrew Catholic Elementary in Welland after a second individual tested positive for the virus.
Officials say this case is connected to the first, so an outbreak was declared.
The only class impacted is the one already in isolation, so no other classrooms have closed.
A second case was also identified at Our Lady of Victory Catholic Elementary School in Fort Erie.
Since this case isn't connected to the first, an outbreak has not been declared.
Individual cases have also been confirmed at St. Augustine Catholic Elementary School in Welland and Notre Dame College School in Welland.
Notre Dame now has four active cases, but does not meet the criteria for an outbreak.
Niagara Region Public Health has reached out to all affected students and staff and advised them to self-isolate.

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