Pig ear dog treats are the suspected source of a multidrug-resistant, multistate Salmonella outbreak among humans, according to the federal Centers for Disease Control and Prevention (CDC).

The CDC reports that whole-genome sequencing analysis of Salmonella isolates from 30 of the 45 outbreak victims predicted antibiotic resistance or decreased susceptibility to ampicillin, ciprofloxacin, gentamicin, nalidixic acid, streptomycin, sulfisoxazole, tetracycline, and trimethoprim-sulfamethoxazole.

Testing of one clinical isolate using standard antibiotic susceptibility testing methods by CDC’s National Antimicrobial Resistance Monitoring System (NARMS) provided comparable results.

“CDC found these antibiotic-resistant infections may be challenging to treat with commonly recommended antibiotics and may require a different antibiotic choice,” according to the notice.

The U.S. Food and Drug Administration (FDA) Wednesday first reported that food detectives had linked pig ear dog treats to salmonellosis suffered by 45 people in 13 states from infections with Salmonella enterica serotype I 4,[5],12:i:-

Twelve people have been hospitalized. No deaths had been associated with the outbreak as of the posting of the FDA and CDC notices Wednesday..

The CDC filled in more details a shortly after the FDA announcement, including that epidemiologic evidence shows pig ear dog treats are the likely source of the outbreak. In interviews, 34 of 38 ill people interviewed so far, or 89 percent, reported contact with a dog before getting sick. And 17 out of 24 who provided information, or 71 percent, reported having contact with pig ear dog treats or with dogs who were fed pig ear dog treats.

According to the CDC report, the investigation has not yet identified a common supplier of the pig ear treats.

The Michigan Department of Agriculture and Rural Development (MDARD) collected pig ear samples from bulk bins at retail locations that tested positive for several strains of Salmonella, although not the specific strain connected to this outbreak.

Retail locations wher sampling occurred have removed pig ears from their shelves, according to CDC. And the investigation is following up to see if anyone is sick from the Salmonella strains that were identified through the positive tests.

Public health and regulatory officials in several states are working with the CDC and FDA on the multistate outbreak of multidrug-resistant Salmonella enterica serotype I 4,[5],12:I:-. They are using the PulseNet system to identify illnesses that may be part of this outbreak.

PulseNet is the national subtyping network of public health laboratories coordinated by CDC. DNA fingerprinting is performed on Salmonella bacteria isolated from ill people by using standardized laboratory and data analysis techniques called pulsed-field gel electrophoresis (PFGE) and whole genome sequencing (WGS).

CDC PulseNet manages a national database of these DNA fingerprints to identify possible outbreaks. WGS gives a more detailed DNA fingerprint than PFGE. WGS showed that bacteria isolated from ill people were closely related genetically. This means that people in this outbreak are more likely to share a common source of infection.

As of July 2 there had been 45 people infected with the outbreak strain of Salmonella I 4,[5],12:i:-  from 13 states. A list of the states and the number of cases in each can be found on the CDC’s Map of Reported Cases page.

Illnesses started on dates ranging from Nov. 18, 2018, to June 13 this year. Ill people range in age from less than 1 year old to 81 years old, with a median age of 23. Fifty percent were female. Of 39 ill people with the information available, 12 or 31 percent, reported being hospitalized.

Illnesses might not yet be reported due to the time it takes between when a person becomes ill and when the illness is reported. This takes two to four weeks or more, according to the CDC.

The FDA is also working with impacted firms to remove pig ears from the marketplace and identify other places wher they were distributed.

Consumers can choose whether to remove pig ear treats from their homes or take steps to prevent Salmonella infection, FDA said.

Salmonella can affect both human and animal health. People with symptoms of Salmonella infection should consult their healthcare providers. Consult a veterinarian if your pet has signs of Salmonella infection.

Anyone who opts to continue feeding long-lasting treats like pig ears should take precautions, according to public health officials. Keep pig ears away from small children. Watch your pet and pick up after it when done. Keep areas in contact with the treat clean and be sure to wash your hands. Do not allow the animal to lick you, or any member of your family or surfaces in your home.

People infected with Salmonella can develop diarrhea, fever, and abdominal cramps.

Pets do not always display symptoms when infected with Salmonella, but signs can include vomiting, diarrhea that may be bloody, fever, loss of appetite and/or decreased activity level, according to FDA. Infected pets can shed the bacteria in their feces and saliva without showing signs of being sick.

The CDC offers this additional advice for dog owners:

Tips on 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 wher 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.