Ottawa Public Health (OPH) has declared a COVID-19 outbreak at the Ottawa Paramedic Service after two paramedics tested positive last week, according to a statement from the city on Thursday.

Anthony Di Monte, the city's general manager for emergency and protective services, first alerted council to the outbreak in a memo on Wednesday, saying OPH had declared the outbreak based on two related cases, but that COVID-19 was "not widespread throughout the workplace."

The city confirmed Thursday that only two paramedics have tested positive. Both received their test results last week, on Oct. 28 and Oct. 30.

"We cannot be certain where the exposure/transmission occurred. Although paramedics may work with patients who have confirmed or suspected cases of COVID-19, paramedics wear personal protective equipment and adhere to rigorous infection prevention and control practices," said Pierre Poirier, chief of the Ottawa Paramedic Service, in a statement.

A workplace outbreak is declared when two or more lab-confirmed cases of COVID-19 are linked within a two-week period and transmission could have occurred at the workplace.

Darryl Wilton, president of the Professional Paramedic Association of Ottawa, said in an email to CBC News on Wednesday that paramedics face "considerable risk" during the pandemic and the association's primary concern is the health of the two members who have tested positive.

"We are staying focused on their recovery and hope they get through this," said Wilton. "We also want to thank the community for continuing to help paramedics get through this by following the recommendations from public health."

According to Wilton, paramedics have attended 82,000 calls since March 17, while also helping with testing at COVID-19 testing sites and long-term care facilities.

Di Monte's memo says the Ottawa Paramedic Service has undergone a "thorough risk assessment" with an OPH inspector who found the service already has "very strong" infection prevention and control practices in place.

"As a result, Ottawa Public Health does not recommend that the service implement any further mitigation strategies at this time," the memo said.

Paramedics will continue to implement COVID-19 screening processes at the start of shifts, perform enhanced cleaning of common areas and high-touch surfaces, maintain physical distancing and wear masks inside paramedic vehicles, said Di Monte.

It's not clear how many employees are affected by the outbreak, nor how many require testing.