KITCHENER -- St. Mary's General Hospital has declared a COVID-19 outbreak on its fifth floor medicine unit.
The hospital announced the news in a press release issued on Thursday afternoon.
According to the release, the outbreak includes three patients and stems from a third patient who initially tested negative for the virus.
They were reportedly discharged after the negative result, but then readmitted, re-tested and then found to have the virus.
Hospital officials say this is an example of the challenges they face when diagnosing the virus.
"COVID-19 has a long incubation period. Hospitals have seen, in some situations, patients initially test negative and subsequently test positive," Chief of Staff Dr. Peter Potts is quoted in a news release.
"Our clinicians have been re-testing patients where there is a progression of symptoms, or in the absence of another diagnosis, and this is identifying more cases of COVID-19."
St. Mary's President Lee Fairclough stresses that patient and staff safety is the hospital's top priority, noting there are no set criteria for declaring an outbreak but they have decided to do so as a safety measure.
Because of the outbreak, the fifth floor has been closed to routine admissions. Patients can now only be admitted after clinical consultation with Infection Prevention and Control.
The hospital says all patients on that floor have now been tested for the virus, and the results are pending. Staff members who had contact with the patients are being traced, as well.
Patients who have tested positive for COVID-19 have been moved to the sixth floor COVID-19 unit, the hospital says. In the meantime, there will be no more than two patients per room in non-COVID units.
This is the third outbreak declared at St. Mary's Hospital.
On April 18, an outbreak was declared on the sixth-floor COVID-19 unit after staff-to-staff transmission.
That same day, an outbreak was declared in the third-floor 3 East Cardiology Unit. That outbreak involved patient-to-patient transmission and possible patient-to-staff transmission.