Deadly Parasite Threatens Pets Across the U.S., Researchers Warn

In a concerning development for pet owners across the United States, researchers have issued a warning about a potentially deadly parasite that has been found spreading beyond its previously known territories. The parasite, identified as Heterobilharzia americana, commonly known as the liver fluke, poses a severe risk to dogs, with cases of infection leading to fatal outcomes in some instances.

Historically confined to Texas and other Gulf Coast states, the liver fluke has now been discovered as far west as California, marking a significant and worrying shift in its geographical spread. Experts at the University of California Riverside found the parasite in areas along the Colorado River where it runs through Southern California, a region previously thought to be free of this dangerous organism.

The liver fluke is a flatworm that causes canine schistosomiasis, a disease that affects the liver and intestines of dogs. If left untreated, the infection can lead to death. "Dogs can die from this infection, so we are hoping to raise public awareness that it’s there," said UCR nematology professor Adler Dillman. The discovery came after several cases of infection were reported in local dogs, prompting researchers to investigate the waters in Riverside County.

Transmission of the parasite occurs through a snail host, with the research team collecting more than 2,000 snails along the banks of the Colorado River and examining DNA to identify the presence of the snails and the flatworm. The findings revealed a wider distribution of the parasite than previously reported, underscoring the urgent need for effective control strategies to prevent further infections.

Symptoms of canine schistosomiasis may include lethargy, loss of appetite, weight loss, diarrhea, vomiting, coughing, increased drinking and urination, and other signs indicating liver and intestinal issues. Young, large breed, hunting, or herding dogs are particularly susceptible to this parasite. Public awareness and prevention are crucial in safeguarding pets from potentially life-threatening parasites, especially in regions where the parasite's presence has been confirmed.

While Heterobilharzia americana does not pose a direct threat to humans, it can cause a swimmer's itch, a skin rash, upon contact. However, the primary concern remains the well-being of pets, with veterinarians recommending close monitoring and prompt treatment for infected dogs to prevent severe complications.

This discovery underscores the importance of public awareness and vigilance in protecting pets from potentially life-threatening parasites. Pet owners are advised to be cautious about the waters in which they allow their pets to swim and to seek veterinary care if their dog exhibits any symptoms indicative of infection.