Record number of potentially deadly strep A infections in Canada

Canada’s public health agency has logged a record number of potentially deadly strep A infections, particularly in children under the age of 15. At least six children have died in Ontario.

“Early laboratory data indicates that [invasive group A streptococcus] disease activity in 2023 was higher compared to pre-pandemic years, particularly in children under 15 years of age,” a Public Health Agency of Canada (PHAC) spokesperson said in an emailed statement shared with CTVNews.ca.

As of Jan. 9, PHAC’s National Microbiology Laboratory has logged more than 4,600 cases from 2023, which is the highest annual total ever recorded in Canada and a more than 40 per cent increase over a previous peak in 2019. According to PHAC, invasive group A streptococcus is endemic in the country, with 2,000 to 3,000 cases reported annually in recent years.

“The previous peak occurred in 2019, with 3,236 isolates submitted,” the PHAC spokesperson explained. “The largest increases continue to be detected in children under 15 years of age.”

Infections from group A streptococcus bacteria are typically mild and cause strep throat, which can usually be treated with antibiotics. More severe and invasive infections are much less common, but potentially deadly.

Invasive group A streptococcus occurs when bacteria causes a deeper infection, such as in the blood. Invasive group A streptococcus can cause lung infections like pneumonia, debilitating flesh-eating disease, or even toxic shock syndrome, which is when bacteria produces toxins that cause organs in the body to stop functioning. Approximately one in 10 people die from invasive infections, according to a U.S. study. Serious outcomes can include amputation and major organ damage.

A Jan. 11 report from Public Health Ontario says that 48 people have died from strep A infections in the province since October, including 23 people aged 65 or older and six children under the age of nine.

“This is higher than the proportion of [invasive group A streptococcus] cases within the same age group that had a fatal outcome reported in the same reporting period for the previous season… and exactly half of the total number of pediatric deaths reported in the entire 2022-23 season,” the Ontario report said.

Provinces like B.C. and Manitoba have also reported a recent increase in cases.

Dr. David Fisman is a physician and epidemiologist, as well as a professor at the University of Toronto’s school of public health. Fisman says that viral infections like COVID, influenza and RSV can make people more vulnerable to subsequent bacterial infections like strep, which could be driving new cases.

“They seem to do this by killing some of the immune defences in the upper airway, ‘setting the table’ for invasive infection,” Fisman explained. “Canadians should be aware and appropriately concerned about this, as invasive group A streptococcal infections (as opposed to ‘strep throat’) is a serious and life threatening infection.”

Health officials say you should seek medical attention if you believe you have a group A streptococcus infection. Initial symptoms may include fever, sore throat and mild skin infections like rashes, sores and blisters. Streptococcus bacteria can be transmitted through direct contact with infected skin wounds, or from fluids in the nose and throat that can be spread when an infected person coughs or sneezes.

“Antibiotics are used to treat both invasive and non-invasive [group A streptococcus] diseases,” PHAC explains. “Early treatment may make symptoms less severe or prevent more serious complications.”

PHAC says invasive group A streptococcus has been “a priority for monitoring and control” by provincial, territorial and federal authorities for more than two decades, and that all cases “must be reported” to public health authorities.