What is walking pneumonia, and why are medical experts talking about it?

Local health officials say walking pneumonia cases are rising.

According to a Public Health Ontario (PHO) report, published at the end of November, the province has seen the highest number of walking pneumonia cases since it began tracking the data in 2019. Of the 4,069 cases examined so far by PCR testing, 733 tested positive, or 18 per cent.

Compared to 2023, the health agency reported 23 positive cases out of 2,542 throughout the year, representing less than one per cent. In 2019, there were 137 positive cases out of 2,368, or 5.8 per cent.

Middlesex London Health Unit Medical Officer of Health Dr. Alex Summers said that there’s a reason that this year’s surge is cause for alarm, “The reason why doctors and nurses are paying attention to walking pneumonia this year is that if it is a milder illness that's caused by the mycoplasma bacteria, it requires a different type of antibiotic.”

The PHO noted the percentage of specimens really started to rise in May and spiked in August, when it reached nearly 30 per cent of cases.

The health agency also revealed most cases were seen in children, particularly those between the ages of five and 17 which accounted for 45 per cent of all cases. Kids under the age of four accounted for 25.5 per cent of case.

“So what we're experiencing is people who get sick with a respiratory illness, it might progress to a pneumonia,” explained Summers. “And our first line antibiotics may not help those symptoms to go away. And so it's really critical that clinicians, doctors and nurse practitioners are aware that this is happening so that they can modify their treatment appropriately when they need to.”

- with files from CTV News Toronto’s Alex Arsenych