Skip to Content

UCR scientist warns pet owners of dog-killing parasite in the Colorado River

Heterobilharzia americana is a virus that affects dogs

YUMA, Ariz. (KYMA, KECY) - Scientists confirm a dog-killing flatworm has been found in the Colorado River.

The Colorado River runs right by Yuma County and parts of California, and scientists want to warn pet owners of the risks.

"We’re hoping that by getting this information out. All of the vets and dog owners are aware that this parasite is a potential cause for those symptoms," said Dr. Adler Dillman, UC Riverside Professor and Chair of the UCR Nematology Department

Over the last five years, vets in Los Angeles, Orange, and Riverside counties have found 11 cases of the virus called Heterobilharzia americana.

Dr. Dillman said the parasite is common in Gulf states like Florida and Texas.

“We did some sampling in the Colorado River in California and indeed both the snails that can host this parasite and the parasite itself is present in the Colorado River," said Dr. Dillman. "And what it means for pet owners is if they get into the river with their pets- their pets are at risk”

I visited a local dog park and talked with some Yuman dog owners who said they were unaware of the parasite.

Dogs and other mammals can become infected when they drink river water.

When asked if it could infect humans too, Dr. Dillman assured that scientists, "are pretty confident that it cannot infect people, but it can cause pretty significant disease in dogs. In fact- it can lead to death in dogs”

A few symptoms include fever, vomiting, and weight loss.

Thankfully, it is easy to diagnose and treat. Pet owners can visit their local vet for medicine to clear the infection, so their dog can still live a long healthy life.

Article Topic Follows: Local News

Jump to comments ↓

Author Profile Photo

Danyelle Burke North

Danyelle Burke North joined the KYMA team in March 2024 as a reporter.

If you have any story ideas, you can contact her at


KYMA KECY is committed to providing a forum for civil and constructive conversation.

Please keep your comments respectful and relevant. You can review our Community Guidelines by clicking here

If you would like to share a story idea, please submit it here.

Skip to content