DES MOINES, Iowa (AP) — Three additional cases of a dog disease that can be passes to humans have been linked to an Iowa breeder. The Iowa Department of Agriculture and Land Stewardship says three additional cases of canine brucellosis have been confirmed in dogs linked to a commercial breeding facility for small dogs in Marion County.

Anyone who obtained dogs from the breeder Double G Kennels, which is also known as IowaPuppies.com, is encouraged to have their dogs tested. Of 200 small dogs sold during a sale at the kennel in May, nine have tested positive for the disease.

Signs of the disease in a dog include infertility, spontaneous abortions and stillbirths. State health officials say symptoms for humans include fever, sweats, headache, joint pain and weakness.

The department says the threat to most pet owners is very low.