The outbreak at the Greater Niagara General Hospital is spreading.
At least 21 patients and staff across three units are now infected with COVID-19.
Niagara Health says Trillium, Rainbow and Unit D are all impacted.
A staff member in one unit tested positive for the virus on Friday, prompting Niagara Health to declare the first outbreak.
A second outbreak was called on Saturday, after another staff member in a different unit tested positive.
Efforts are underway to control the spread and contain the virus.

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