LONDON, ONT. -- Medical Officer of Health Dr. Chris Mackie says the Middlesex-London Health Unit’s initial investigation found several lapses in obeying pandemic protocols.

"Most staff were certainly respecting the rules, but we did have situations where staff were not, in terms of mask wearing and physical distancing," explained Dr. Mackie during a media briefing on Thursday.

A more detailed investigation is being undertaken by the London Health Sciences Centre.

"Was it preventable? That is difficult to answer when we have ongoing contact tracing to determine what the cause is," says Dr. Adam Dukelow, Chief Medical Officer at LHSC.

Dr. Dukelow tells CTV News he has received no evidence of a festive gathering or potluck meal, however, he admits two other possible sources of transmission have subsequently been addressed.

Prior to the outbreak, more staff were moving between hospital floors than is now being permitted.

Also, concerns were expressed by staff about inadequate space for physical distancing during meal breaks.

"We may end up saying at the end of this investigation, that there were multiple small contributing factors and a virus that’s spread is exponentially," adds Dr. Dukelow.

According to the health unit, there have been total of 124 cases of COVID-19 acquired at University Hospital during the outbreak.

And on Thursday, two more deaths were attributed to the outbreak, bringing the total number to 11.

Dr. Mackie warns that the outbreak was not contained to the hospital building, with at least 24 secondary cases discovered in the community so far.

The outbreak inside the hospital is now 3 times the size of the region’s next largest outbreak during the pandemic— and the death rate stands at almost 10 per cent.

While the outbreak is expected to result in tougher pandemic restrictions for everyone in London and Middlesex County, Dr. Mackie cautions the public from laying blame on hospital staff.

"I don’t think it’s fair for one part of our society to cast blame on the other. This is happening in many places," he said.

"The public are welcome to point the finger where they’d like. We are in the midst of a worldwide pandemic," adds Dr. Dukelow. "Do I wish we weren’t in the outbreak situation at UH? Absolutely. Do we regret the situation we’re in? Yes."