TORONTO -- Eighteen flights arriving in Canada from international destinations since the start of August have had people on board with COVID-19.

According to the federal government, the flights landed in Canada between Aug. 1 and Aug. 4. They all had passengers who tested positive for COVID-19 after arriving in Canada. 

Eight of the flights arrived in Toronto, while seven landed in Montreal, one in Vancouver and one in Calgary. 

The government is still advising Canadians against non-essential international travel but for those who do, it is mandatory to self-isolate for 14 days, regardless of whether or not they are experiencing symptoms of COVID-19. 

Passengers are not notified directly by federal public health authorities to get tested, though the government acknowledges those onboard affected flights "may have been exposed to COVID-19."

Speaking to CTVNews.ca last month, Air Canada spokesperson Peter Fitzpatrick said that anyone concerned they may have been exposed to the disease should contact their doctor. 

"However, it is important to understand the incidence of individuals contracting a communicable disease inflight is very low. As evidence, consider what are called 'cluster outbreaks,' where a group of people contract a disease at the same time and location. These are rarely if ever tied to modes of travel, whereas you often see reports of outbreaks arising from funerals, bars or other gatherings," Fitzpatrick said. 

An Air Canada fact sheet says, "the reasons for the apparently low rate of in-flight transmission are not fully determined but are thought to include a combination of the lack of face-to-face contact, and the physical barriers provided by seat backs, along with the characteristics of cabin air flow."

Pre-flight screening, temperature monitoring and mandatory face coverings are "also seen to be effective."

Both WestJet and Air Canada, two of the biggest airlines in North America, began selling their middle seats again on July 1 after months where the option was removed to aid in physical distancing.

The international flights since Aug. 1 with COVID-19 cases include:

  • Air Transat flight TS831 from Punta Cana to Toronto on Aug. 1
  • United Airlines flight UA375 from San Francisco to Vancouver on Aug. 1 
  • Air Transat flight TS893 from Cancun to Montreal on Aug. 1
  • Air France flight AF034 from Paris to Montreal on Aug. 1 
  • Air Canada flight AC1297 from Punta Cana to Montreal on Aug. 1
  • Air Canada flight AC1241 from Cancun to Montreal on Aug. 1
  • Pakistan International Airlines flight PK797 from Lahore to Toronto on Aug. 2
  • Etihad Airways flight EY141 from Abu Dhabi to Toronto on Aug. 2
  • Air Canada flight AC992 from Mexico City to Toronto on Aug. 2
  • United Airlines flight UA3488 from Newark to Toronto on Aug. 3
  • Qatar Airlines flight QR763 from Doha to Montreal on Aug. 3
  • Air Canada flight AC7682 from Chicago to Toronto on Aug. 4
  • Air Canada flight AC849 from London to Toronto on Aug. 4
  • Air Canada flight AC879 from Switzerland to Toronto on Aug. 4
  • Tap Air Portugal flight TP253 from Lisbon to Montreal on Aug 4.
  • Delta Airlines flight DL7203 from Atlanta to Calgary on Aug 4.
  • Air Canada flight AC870 from Montreal to Paris on Aug 4. 
  • AeroMexico flight AM680 from Mexico City to Montreal on Aug 4. 

The information posted to the government's website is provided by provincial and territorial health authorities, international health authorities and public website.

The data on the government's website is updated once a day.

With files from CTVNews.ca writer Meredith MacLeod.