Influenza and Haemorrhagic fever specialist, Dr Gregory Taylor, says cases likely occurring together
The Toronto Public Health has confirmed for the first time in the city’s history that three cases of the deadly Omicron variant influenza have been reported in a single cluster.
Canada’s national carrier, Air Canada, has cancelled and rescheduled nearly 1,500 flights from Toronto to three US cities: Los Angeles, New York and Boston to help ensure a steady flow of passengers at Canadian airports as the company worked with local authorities to repatriate passengers and crew returning from the three destinations.
Steve Adams, vice-president of corporate communications and investor relations for Air Canada, said in a statement: “We would like to extend our sincere appreciation to our customers for their understanding, and our team members for their commitment to safety.”
By Friday afternoon Canada’s chief public health officer had reported that the virus, also known as bird flu, had been confirmed in four patients in the northern Ontario city of London.
Scientists do not yet know how the outbreak in the city of 635,000 people began or what caused it.
A fourth patient is believed to have contracted the virus at a different location but is confirmed to have a similar strain. All four cases of the virus have been connected to the same hospital.
Dr Gregory Taylor, Canada’s public health officer, said all of the cases were spread across the whole city, suggesting the widespread transmission of the virus has occurred simultaneously.
All three were adults.
“It was such a small cluster and they’re all connected,” Taylor said. “There’s not been any introductions of the virus into the population and none of them had any symptomatic disease, nor did they have any history of travel to the three US or Mexico infected locations, so it’s possible that this has been a family member, a close relative, that has brought it into the city with them.”
The virus can be passed between members of the same family, but it can also be carried by infected birds and can be transmitted from person to person by kissing, close contact or simply breathing in the same air. The four Toronto patients had no recent travel history or close contact with birds.
Taylor said patients in the latest cluster were infectious between 6 and 15 days before showing symptoms of the virus.
The individuals are currently in isolation at St Joseph’s Healthcare in London and are not yet showing symptoms.
Jordan Robson, a professor of virology at the University of Manitoba, said it was important to say there was no indication of widespread transmission of the virus.
“The clusters are closely connected and that’s always something that’s not really well understood,” he said. “Viruses continue to be in the environment in ways that we don’t fully understand.”
But he said it was troubling to hear about outbreaks in close proximity to city centres and hospitals.
“It is rare,” he said. “We’ve had two or three of these cases recently in the US, but it’s been really the last decade or so. This is the first time it’s happened in Canada.
“They’re usually clustered around poultry or backyard poultry, but this seems to be in people as well, not necessarily close to poultry or chickens.”