Pet owners in three Southern California counties have been advised of a dangerous parasite being reported by local veterinarians and impacting at least nine dogs.
According to a press release from Riverside County Department of Animal Services, schistosomiasis is triggered by exposure to freshwater parasites, and recently has led to seven cases in Orange County and two in Riverside County. Previously, Los Angeles County experienced two diagnosed cases in 2018.
“Infected dogs may not show signs of illness early in the course of the disease, yet this is when treatment tends to be most successful,” Sara Strongin, chief veterinarian at Riverside County Department of Animal Services, said in the release.
Canine schistosomiasis is caused by a freshwater parasite called Heterobilharzia americana not considered native to Southern California, according to the release, which puts its habitat as the American South and Gulf Coast states.
Strongin clears up the mystery of origin by suggesting that the dogs got the parasite while swimming in the Colorado River on a camping trip with their families in an area along the California/Arizona border. The presence of this parasite in Southern California, however, has not been ruled out, the release also said.
Dog owners are being alerted since schistosomiasis can not only produce sickness, but take the pet's life in severe cases. On the other hand, humans do not have life-threatening exposures, the county said.
“Although humans may develop a self-limiting rash after contact with contaminated water sources, it is important to recognize that the disease is not transmitted directly to humans or between dogs,” Strongin said. “So, there is no need for grave concern, particularly if your family and pets do not swim or play in freshwater sources.”
The statistics on this parasite in Southern California highlight the need for early discovery and treatment. As reported by the county, a total of 11 cases have appeared from October 2018 to January 2023; one of the dogs died from exposure, but the rest of the pets got better after treatment.
A dog with schistosomiasis may suffer diarrhea, weight loss, lethargy and possibly fever with a slow, gradual onset of symptoms, sometimes not appearing at all until the disease has progressed into later stages, the county said. The best way to ward off schistosomiasis in dogs is to eliminate the chance of getting an infection by eliminating contact with natural freshwater sites like streams, rivers and lakes.
Visit the county website to learn more about schistosomiasis or reach out to shelterinfo@rivco.org.