New documents show at least 450 probable cases of measles were identified in Alberta as of Oct. 23.Ahmed Zakot/Reuters
The Alberta government rejected expert advice to expand public reporting of measles to include probable cases, despite the measure being supported by local and provincial public health officials, documents obtained by The Globe and Mail show.
Since the outbreak began in Alberta last spring, only confirmed cases of measles have been publicly reported. New data provided through a Freedom of Information request show at least 450 probable cases of measles have also been identified in the province, bringing the total to nearly 2,500.
These numbers provide a more accurate portrayal of a crisis that has gripped Alberta, one of the two provinces at the centre of a countrywide outbreak that lost Canada its long-held measles elimination status last month. The new data show Alberta, not Ontario as previously understood, has the highest case count of any province, despite having a much smaller population. Ontario publicly reports probable cases.
A probable case is more than just a guess. It is classified as such after a health care provider or public health practitioner assesses an individual who is showing symptoms and has been exposed to another case or visited an area of known measles activity.
The documents include a briefing note prepared in June – at the height of the province’s outbreak – for Minister of Primary and Preventative Health Adriana LaGrange. She was advised by health experts that including probable cases in public reporting would give Albertans a “complete and more accurate understanding” of the outbreak.
“Alberta’s government is committed to protecting Albertans by taking action to reduce the risk of infectious diseases. This includes keeping the public informed with up-to-date measles case counts in the province,” said the briefing note, which is partly redacted.
“Expanding public reporting to include both confirmed and probable measles cases is a key step in maintaining transparency and keeping Albertans informed.”
The Globe previously reported that Premier Danielle Smith’s government delayed efforts by public health officials, such as implementing visitor restrictions in hospitals, to bring the measles situation under control. The lifting of masking measures in certain hospitals has also come under scrutiny.
The new documents, again, raise questions about Alberta’s measles response.
Maddison McKee, press secretary to Ms. LaGrange, defended the government’s strategy. She said Alberta follows long-standing national disease surveillance practices.
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“We have not historically reported probable cases, in part because they are unconfirmed and may later be ruled out. This approach aligns with other disease and illness reporting in the province,” Ms. McKee said Friday.
The documents show 450 probable cases were identified in Alberta as of Oct. 23. Two pregnant individuals, as well as one person who was previously hospitalized owing to a measles infection, were among the probable cases, as of mid-July.
In October, the government confirmed a premature baby who contracted measles in utero died. It is the only death associated with the provincial outbreak. Few details have been provided about the case, including when or where the death occurred.
The June briefing note said reporting probable cases would also provide a better understanding of severe outcomes, such as death and hospitalizations, in the province.
Alberta’s public dashboard on measles contains information on hospitalizations but only for confirmed cases. Nearly 160 Albertans have been admitted to hospital between Jan. 1 and Nov. 29, 15 of whom have required intensive care. It is unclear how many probable cases ended up in hospital.
Additionally, Ms. LaGrange was told in June that updating Alberta’s public data would bring the province in line with national practices, helping with consistent data comparisons across provinces. It noted that public health officials supported this change, yet the advice was ignored.
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Canada’s outbreak began in October, 2024, in New Brunswick. Measles is one of the world’s most contagious diseases, which allowed it to spread easily across the country, largely infecting areas with low vaccination rates. Mennonite communities in Alberta and Ontario have been particularly hard-hit.
The crisis has significantly eased since then but new cases continue to pop up in Alberta, in addition to other provinces, such as Manitoba and Saskatchewan. Ontario, however, declared an end to its outbreak on Oct. 6 after no new cases were reported for 46 consecutive days – double the incubation period for measles.
Ms. McKee, in her statement, said case numbers in Alberta have greatly decreased since the outbreak’s peak over the summer, noting that one case is currently active and hospitalizations have remained low.