Researchers Recently Confirmed The Presence Of A Potentially Deadly Dog Parasite In A Stretch Of The Colorado River That Flows Through California

Researchers at the University of California-Riverside (UCR) have made the first-ever confirmation of a potentially deadly dog parasite located in a stretch of the Colorado River flowing through California.

The parasite known as Heterobilharzia americana, commonly called liver fluke, is a type of flatworm that, until now, was predominantly identified in Texas and states along the Gulf Coast.

This discovery marks the first occasion it has been detected so far west. Sadly, this worm is responsible for canine schistosomiasis, a disease that affects dogs’ livers and intestines.

“Dogs can die from this infection, so we are hoping to raise public awareness that it’s there. If you’re swimming in the Colorado River with them, your pets are in peril,” said Adler Dillman, a nematology professor at UCR.

Upon hearing about instances of the infection in local dogs, Dillman assembled a research group and headed to Blythe, a town on the border east of Joshua Tree National Park in Riverside County. Each of the affected dogs had been swimming in the nearby river.

The disease is transmitted through a snail that carries the worm. So, the research team collected more than 2,000 snails from the riverbanks. In their recent report, they detail how DNA analysis was used to verify the identities of both the snails and the flatworm.

“We actually found two species of snails that can support H. americana in the river in Blythe, and we found both snails actively shedding this worm. Not only was it a surprise to find H. americana, we also did not know that the snails were present here,” Dillman explained.

Once a flatworm transforms inside a snail, it emerges with a singular mission: to infect a mammal. At this phase, it can only live independently for about 24 hours. Infection takes place when a dog or a raccoon is either in the water or drinking from it. Afterward, the worm enters the veins in the intestinal lining, where it matures into an adult and reproduces.

But the issue isn’t the adult worms living in the veins; it’s the eggs that travel to the lungs, spleen, liver, and heart. The immune system attempts to combat this, leading to the formation of hard clusters of immune cells known as granulomas. Over time, this results in the organs ceasing to function properly.

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