Officials with Canada Post say an outbreak of COVID-19 has hit their massive facility.
They say 121 workers have tested positive since the start of the new year.
About 4,500 people work at the Dixie Road location.
A spokesman says public health officials have indicated most of the cases came from the broader community.
Nurse Practitioner Impacting Niagara Falls ER
Niagara Health says wait times shrinking
Grimsby, Port Colborne Honour Remembrance Day
Services also held in Niagara Falls, St. Catharines
St. Catharines Man Charged with Drug Dealing
Police say they've been investigating an individual over the last few months
Wainfleet Man Wins Lottery... 1st Time
He says his wife didn't believe him, she then rolled over and fell back asleep
MP Plans to Hear More Vaccine Injury Stories
Dean Allison, of Niagara West, says many people didn't get to speak in September
Cash Registers Stolen in Thorold B&Es
Motel Fire Considered Suspicious
Fire fighters were called last week to a motel in Niagara Falls
Frank Campion Named Niagara Regional Chair