After new reports of polio cases abroad, and virus samples in the wastewater of several other developed countries, Canada intends to start testing wastewater from a number of cities “as soon as possible,” CBC News has learned.
The Public Health Agency of Canada (PHAC) already works to monitor polio activity around the world, a spokesperson said in an email response to CBC News questions.
Currently, PHAC’s National Microbiology Laboratory in Winnipeg does have the diagnostic tools available to test samples for poliovirus. Any suspected positive Canadian samples of poliovirus will be sent to that lab for further laboratory analysis and confirmation, with results shared with the respective local health authorities “so appropriate public health measures can be taken if necessary.”
According to the statement, PHAC has been communicating with national and international partners who are experts in this field to finalize a wastewater testing strategy. It will be testing wastewater samples that were collected earlier this year from “key high-risk municipalities” to determine if polio was present prior to the reported international cases.
PHAC will also be sending samples to the U.S. Centers for Disease Control and Prevention for additional confirmation.
“However, it is important to acknowledge that accurately testing wastewater for poliovirus is a developing science,” the statement continued. “For example, wastewater detections can be affected by extreme precipitation events, such as flooding in a community.”
Reports of polio in U.S., U.K., Israel
On Wednesday, British health authorities announced they will offer a polio booster dose to children aged one to nine in London, after finding evidence the virus has been spreading in multiple regions of the capital.
The agency said it was working closely with health authorities in the U.S. and Israel, as well as the World Health Organization, to investigate the links between polio viruses detected in those two countries.
In July, Israel announced a recent outbreak of polio infections appeared to be under control, after multiple people became infected, including a Jerusalem girl who was paralyzed and now requires rehabilitation, according to the Jerusalem Post.
More recently, in the state of New York, one unvaccinated young adult suffered paralysis after a polio infection in Rockland County — an area known for low vaccination rates — which marked the first case reported in the U.S. in nearly a decade.
Outbreaks also remain common in Afghanistan, Pakistan, and parts of Africa — areas of the world where vaccination efforts have not yet eradicated the virus.
Polio can often be asymptomatic, but in some cases, the viral infection can lead to paralysis or death.