A Woodland Hills family was shocked to learn that a brain-infecting parasite called raccoon roundworm was found in their dog in January.
Christian Lopez said he had taken his dog, Ducky, into the vet for a routine examination when doctors found Baylisascaris eggs in her. Lopez said it was the first time he had heard of it, but quickly learned how serious it is.
Doctors found out Ducky had raccoon roundworm during a routine examination. CBS LA
The Department of Public Health said it’s the first formal report of raccoon roundworm in a dog in Los Angeles County history. Dr. Julio Lopez, whose practice treated Ducky, said in all of his years, he’s “Never seen a case like this.” Dr. Lopez said if parasites go untreated, pets can develop severe illnesses.
“A pet may go blind from parasites or may present with having seizures as well,” Dr. Lopez said.
Transmission most often occurs when people or pets ingest food or water contaminated with raccoon feces. Doctors say if animal waste is left to dry out for about 2 to 4 weeks, the parasite’s eggs can cause an infection. Dr. Lopez clarified that owners can’t get it directly from their pets.
“You can still cuddle with your pet, you can snuggle with your pet and not be afraid of catching this parasite directly,” Dr. Lopez said.
Public Health officials said the risk to the general population is extremely low. Fewer than 10 human cases have been reported in California since 1993, but officials felt it was important to send out an alert after Ducky’s infection.
In 2024, two children in the South Bay were infected with raccoon roundworm. Dr. Dawn Terashita, the associate director of Acute Communicable Disease Control at the LA County Department of Public Health, said the cases happened around the same time but were unrelated. Terashita said it’s believed that the children put raccoon feces in their mouths and got infected. One child had gone to the beach, and the other child had been exposed to a raccoon latrine, which is an area where a raccoon routinely expels its waste.
“Any child or human who has a tendency to put things into their mouth is what we consider high risk,” Terashita said. “Toddlers put everything in their mouth and some humans, especially adults and even older kids, have a disease called ‘pica,’ where they put non-food items into their mouth.”
If untreated, raccoon roundworm can cause severe health complications, including brain damage and death. CBS LA
Terashita said, thankfully, both children recovered with treatment, but added that infections in humans can be very severe and can cause complications like liver failure, coma, or even death.
One thing Terashita said about roundworms is that it is often mistaken for ringworms.
“They call it ringworm; it’s not a worm and it’s a fungus, like athlete’s foot, like jock’s itch,” Terashita said. “Roundworm, which is what we’re talking about, is an actual worm. It’s an actual parasite; it’s called a roundworm because it’s a worm and the body of the worm is like a tube, it’s round.”
Doctors say raccoon roundworm isn’t transmitted from person to person, which is why doctors say picking up after your pet is important to prevent transmission.
The Lopez family said they had taken Ducky to the vet after adopting her from a family friend, thinking a bit of preventive care would pay off.
“I know it’s going to be expensive, but it’ll be a lot more expensive later if you catch something too late,” Lopez said.
How to prevent a raccoon roundworm infection
Since doctors say raccoon roundworm isn’t transmitted between individuals, it’s best to take preventive steps to minimize other forms of infection.
Ways to prevent raccoon roundworm infection:
- Picking up after pets in your yard
- Clearing the yard of other animal feces
- Safely removing raccoon latrines
- Keeping outdoor trash bins out of reach of animals
- Not leaving food out in your yard for pets
- Trimming trees to keep raccoons from climbing onto roofs
- Making sure children wash their hands after playing in the dirt
- Wearing gloves while gardening
- Keeping sandboxes and other water sources covered when not in use
The U.S. Centers for Disease Control and Prevention (CDC) says raccoon roundworm eggs can take 2 to 4 weeks to become infectious, so making sure to clear any feces or other possible contaminants is important.
The CDC also says that most household cleaning items will not be able to kill roundworm eggs, but using heat or boiling water will.