An outbreak of drug-resistant salmonella that's sickened dozens of people has been linked to having contact with pig ear dog treats, according to the Centers for Disease Control. 

The CDC warned Wednesday there have been 45 people infected with this particular outbreak strain of salmonella that has been reported across 13 states. 

Epidemiologic evidence indicates that contact with pig ear dog treats is the likely source of the outbreak, the CDC said. However, the investigation has yet to identify a common supplier of pig ear treats that can be linked to the outbreak.  

The majority of people who became ill reported having contact with a dog before getting sick. 

As of July 2, there have been cases reported in California, Illinois, Indiana, Iowa, Kansas, Massachusetts, Michigan, Missouri, New York, North Dakota, Pennsylvania, South Carolina and Wisconsin. 

RELATED: Map of cases from Salmonella outbreak linked to pig ear treats

While there's no recall linked to this outbreak at this time, the CDC has posted advice to dog owners that include tips for staying healthy while feeding your dog: 

- Always wash your hands thoroughly with soap and water right after handling pet food or treats, including pig ears.

- When possible, store pet food and treats away from where human food is stored or prepared and away from the reach of young children.

- Don’t use your pet’s feeding bowl to scoop food. Use a clean, dedicated scoop, spoon, or cup.

- Always follow any storage instructions on pet food bags or containers.

As part of the investigation into the outbreak, Michigan officials tested pig ears from stores where those who got sick said they bought the treats. While testing didn't find the outbreak strain, other strains of salmonella were, according to the CDC.