Canada researchers say parasite could spread after being found on sick lake man

PHILADELPHIA — The man presumed to have contributed to the mysterious outbreak of cryptosporidium in Ontario is under 24-hour watch in a hospital unit there as the province continues to scan its waterways and…

Canada researchers say parasite could spread after being found on sick lake man

PHILADELPHIA — The man presumed to have contributed to the mysterious outbreak of cryptosporidium in Ontario is under 24-hour watch in a hospital unit there as the province continues to scan its waterways and disease experts predict the strain could spread widely.

Steve Desruisseaux, who had recently recovered from dialysis for renal failure, showed no sign of dying before being found earlier this month with cryptosporidium and water-borne infections in Ontario, where experts say he contracted a type of parasite that multiplies in open water.

The cryptosporidium type cryptosporidium that he had apparently caught is very similar to that involved in a large and very deadly 2014 outbreak in New York City. The parasite ingested during a visit to a river causes serious intestinal illness and can lead to renal failure and death, including on a kidney transplant list.

“We still don’t know how Steve contracted this illness,” said Dr. Gary Kirk, a Public Health Ontario professor who is the pediatric infectious disease specialist supervising Desruisseaux’s care. Kirk spoke Monday after a disease outbreak conference in Philadelphia, where he and others are discussing ways to minimize the effects of cryptosporidium on Ontario’s health care system.

It has been more than six months since the onset of cryptosporidium and the province is still unsure how the man got it.

Doctors in Ontario first treated him for a respiratory infection. Days later, they saw that he had an elevated risk of waterborne diseases, including cryptosporidium.

They asked him to go to New York City, which is treating its water with a bacterium to keep the parasite out of the city’s rivers. Doctors there did a rapid bacterial assay on his kidney test and found he had the strain that was found in the NYC outbreak in 2014.

Both germ strains typically exist at high levels in untreated water, but say there is no scientific evidence to suggest whether humans and animals can accidentally transfer the toxins through bacteria or simply be exposed to them.

For years, the parasite, which can be passed by human feces and can survive many months in water, has been growing more aggressively as it increases the amount of intestinal waste it excretes, according to Nathan Allen, the author of an annual health report issued by Public Health Ontario.

Allen is also a Delaware County, Pa., native who has worked for more than a decade to prevent outbreaks of Cryptosporidium, dysentery and other infectious diseases in the U.S. and Canada.

Cryptosporidium, often referred to as “yogurt bacteria,” is one of the types of fecal pathogen that get into waterways as flooding creates or re-creates stagnant pools of water and grass. That includes hydraulic grates on sewage drainpipes, catwalls and other things on paved surfaces, which house the surface sediment from sewage.

While it usually spreads through clams and mussels, one of the largest recent outbreaks was from single, infected birds swimming in two urban ponds. And about a dozen people have gotten Cryptosporidium from fish they ate contaminated with urine from infected birds, a 2009 report found.

Cryptosporidium is found in numerous reservoirs, lakes and rivers throughout the U.S. and Canada.

Treatment usually involves not killing the parasite but killing the pathogen that causes diarrhea in human beings and in pets.

Ottawa, Ontario, has added 1.8 million cubic meters (68 million cubic feet) of water to its waterways. Hundreds of local farmers have been instructed to wash their tractors and other large machines before leaving the farm because of potential contamination.

Public Health Ontario and the U.S. Centers for Disease Control and Prevention are working to educate people on the symptoms of the various cryptosporidium infections and the steps they can take to prevent them.

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