Canadians sickened by tainted beef from XL Foods should be tested annually over the next few years for lingering health problems that can be caused by E. coli, says a researcher who studied the long-term effects of infection in residents of Walkerton, Ont.
In 2000, the municipal water supply in Walkerton was contaminated with E. coli 0157:H7, the same toxin-producing strain that has led to the massive recall of beef from Alberta's XL plant and has so far sickened 11 Canadians in four provinces.
In the water-borne outbreak more than a decade ago, 2,300 residents developed an E. coli infection and seven of them died, including one child. Twenty-eight of those stricken developed hemolytic uremic syndrome, or HUS, which occurs when a toxin from the bacteria damages blood vessels, leading to kidney failure, gastrointestinal complications and neurological effects.
A series of followup studies of affected residents found an increased risk of high blood pressure as well as related kidney damage and cardiovascular disease.
Dr. William Clark, a kidney specialist at Western University who led those studies, said he expects individuals who became ill from the contaminated beef in recent weeks would also be at risk of such long-term health problems.
"And probably they need to be followed up on an annual basis for the first two or three years to determine if they have developed any of these abnormalities, which can actually be treated," Clark said Tuesday from London, Ont.
"But the important thing is they need to be followed up and assessed. They need to have some simple screening tests in terms of their kidney function."