VANCOUVER -- Four more flights into Vancouver have been added to the B.C. Centre for Disease Control's list of COVID-19 exposures.

Passengers who were on an Air Canada flight from London that landed in Vancouver on July 28 should watch for symptoms of the virus, the BCCDC warned in a tweet posted Tuesday evening.

Then, on Wednesday evening, the centre tweeted that three more flights had been added to the list.

The London flight's number is AC855, but it was also operated in partnership with Lufthansa under flight number LH6812. Rows 12 to 14 and 18 are most at risk of exposure.

Two of the other three flights were from Seattle to Vancouver and operated by Delta. On July 20, Delta flight 4523 had a confirmed case of COVID-19 on board, and on July 29, Delta flight 3898 was in the same situation. Affected rows were not reported on those two flights.

The final addition to the list was Aeromexico flight 696 from Mexico City to Vancouver on July 29. This marks the fifth time in the last month that a person on Aeromexico flight 696 has been found to have COVID-19. The daily flight from Mexico City to Vancouver International Airport also had the coronavirus on board on July 8, July 15, July 17 and July 22.

Passengers in rows 19 to 27 were at the greatest risk of exposure on the latest flight.

Because each of the four flights added to the list in the last two days were international, everyone who travelled on them is required to self-isolate for 14 days and monitor for symptoms of the virus. 

B.C. health officials no longer directly contact people who were seated near a confirmed case of COVID-19 on a domestic flight. Instead, the BCCDC provides updates on flights with confirmed cases as it becomes aware of them.

A full list of recent exposures can be found on the BCCDC website