Bird flu, measles top 2025 concerns for Canada's chief public health officer

As we enter 2025, Dr. Theresa Tam has her eye on H5N1 bird flu, an emerging virus that had its first human case in Canada this year.

As we enter 2025, Dr. Theresa Tam has her eye on H5N1 bird flu, an emerging virus that had its first human case in Canada this year.

At the same time, Canada's chief public health officer is closely monitoring measles — a virus that was eliminated in this country more than two decades ago, but is making an accelerated resurgence.

H5N1, a strain of highly pathogenic avian influenza viruses carried by wild birds, has been on the rise globally. It has decimated poultry farms in Canada and infected dairy cattle herds in several states south of the border.

But its spread to humans is especially worrisome.

"What I am particularly concerned about is that this virus has demonstrated the capability of a whole range of clinical outcomes, from asymptomatic infection ... all the way to rare cases of severe illness," said Tam in a year-end interview on Dec. 18.

"So it's something that we really need to be very vigilant about.”

Canada's only confirmed H5N1 patient — a teen in B.C. — was severely ill and hospitalized in November. Health officials there have still not been able to determine how the teen got infected.