MONTREAL -- One of the province's worst COVID-19 oubreaks has swept quickly through a long-term care home in Île-Perrot, infecting more than 80 people in just two weeks.

The speed of the outbreak first left the local health board (CISSS) stumped, and the union representing the workers raising alarms over ventilation problems.

In response, the CISSS brought in an external firm Monday to review the ventilation system for the Laurent-Bergevin long-term care home (CHSLD), it said -- and that didn't solve the mystery, though it did suggest some areas for improvement.

"The causes of the spread of the virus within the CHSLD are not yet known despite the extensive investigation underway," said Jade St-Jean, the spokesperson for the Monteregie West CISSS, which oversees the home.

However, the deputy director general of the CISSS requested the ventilation review, and the results are already back a day later, she said.

ONE OF QUEBEC'S BIGGEST OUTBREAKS

The Laurent-Bergevin care home outbreak is one of Quebec's biggest right now, with nearly 50 of the residents -- three quarters of the total number -- infected, and three people dead.

Three dozen staff members are also infected. All those cases appeared in the last two weeks.

The families of residents said they're scared.

"We're powerless," said the husband of one woman living there, who developed a fever a few days ago. He hasn't seen her in 10 days.

"There's just absolutely nothing you can do," he said.

One of the mysteries is why things suddenly went wrong now -- the home fared well during the first wave.

"Right now what we're trying to do is figure it out, make sure we stop the spreading as fast as we can," said St-Jean.

A DEEP DIVE INTO VENTILATION

The union said it's been pointing to aerosol transmission.

"The employer has been questioned many times and a request for intervention has been made to [Quebec's worker safety board]," said Simon Beaulieu, president of the union group CUPE local 3247.

The union asked in particular for "an exhaustive verification of the CHSLD ventilation system," he said.

St-Jean said that the firm hired to review the system said it "meets standards." However, "given the gravity of the situation," it also recommended several measures to increase air flow as much as possible:

  • Improving the building's mechanical ventilation systems
  • Leave some windows half open to provide additional air supply
  • Run the bathroom fans at all times
  • Add portable devices, like HEPA filters, to filter fine particles

"Our teams are busy applying the recommendations of the external firm in order to maximize air circulation in the CHSLD," said St-Jean.

The union also noted it was pleased the home has also succeeded in setting up a negative-pressure "red zone" for positive cases, meaning the air pressure is managed to ensure less air flows out of the red zone -- and it wants the same thing done for a new red zone.

"Negative pressure is a system to limit the spread of contaminants in adjacent areas," Beaulieu, the union leader, wrote.

“Due to the increase in the number of cases, a second red zone has been opened. However, the latter does not have negative pressure ventilation," he said.

Four doctors are now on site trying to care for the sick patients, and vaccination starts this week for staff in the region, which may help.