Health officials in York Region have confirmed a case of COVID-19 in a woman living in a seniors home in Markham, the fourth such facility in Ontario known to confirm novel coronavirus infection.

The executive director of Markhaven Home for Seniors on Parkway Avenue east of Main Street North in Markham told residents and their families of the infection of a woman in her 70s on Friday night.

“In addition to our existing outbreak management plans, we are working closely with York Region Public Health, Public Health Ontario, and the Ministry of Health to ensure we are following correct protocols and that all necessary steps are taken to manage this case,” Mike Bakewell said in the email.

York Region Chief Medical Officer Dr. Karim Kurji said the facility had been experiencing “a respiratory outbreak.”

“Public Health Inspectors visited and ensured all proper protocols in place were being strictly adhered to,” he said. The tests were submitted as part of that protocol. Our investigation on the source of the infection is ongoing, as are implementation of additional measures.

He said the woman remains isolated in her unit inside the home, and has been inside the unit since the moment “symptoms started.”

He said she “is doing well” in isolation.

A number of other residents showing symptoms of respiratory illness have also been tested for COVID-19.

Bakewell said visits to the facility would be restricted to immediately family members visiting those who are acutely ill or in palliative care.

“You will be allowed to come to the home to visit them and you will be supplied with appropriate personal protective equipment (PPE) prior to entering an affected room,” he said.

The outbreak in Markham joins another ongoing outbreak at an Oshawa long-term care facility, a resident of Seven Oaks nursing home in Scarborough who tested positive and another outbreak involving three seniors at Pinecrest Nursing Home in Bobcaygeon, Ont.

The novel coronavirus is believed to be more lethal to those over the age of 70 or people with underlying respiratory or other health conditions.

The vast majority of those infected make a full recovery, most without ever needing hospitalization.

As of Saturday morning, there were 10 known cases of COVID-19 in Markham.