WASHINGTON – Food safety and public health officials are advising consumers to avoid all pig ear pet treats and retailers to stop selling pig ear pet treats as the agencies investigate a link between the treats and human Salmonella infections.

As of Aug. 27, the Atlanta-based Centers for Disease Control (CDC) and Prevention have linked pig ear pet treats with 143 cases of human salmonellosis in 35 states. Investigators counted six different Salmonella enterica serotypes — Cerro, Derby, Infantis, London, Newport and Rissen. Many of the cases are multidrug-resistant, according to CDC, and 33 people have been hospitalized.

The US Food and Drug Administration (FDA) said Dog Goods USA LLC, Tobyhanna, Pennsylvania; Edison, New Jersey-based Lennox Intl Inc.; and Pet Supplies Plus launched product recalls after the companies’ products were associated with cases in the outbreak. Some of the recalled treats tested positive for Salmonella, and further testing is ongoing to identify the strain or strains.

The FDA traced some of the affected treats to manufacturers in Argentina, Brazil and Colombia. On Aug. 22, the FDA updated an import alert to include three firms that presented pig ears for import that then tested positive for Salmonella: Custom Pet S.A.S (Colombia), Suarko SRL (Argentina), and Anabe Industria e Comercio de Proteinas (Brazil).

“To date, human Salmonella infections have been linked to pig ears imported from Argentina, Brazil and Colombia,” FDA said. “However, these pig ears do not account for all the illnesses in this outbreak.

“Pig ears in bulk bins (not packaged or wrapped) may be comingled from multiple sources which does not allow the products to be distinguished,” the agency added. “In addition, effective product irradiation may not have occurred for bulk products and for packaged or individually wrapped products.”

Companies placed on the import alert cannot import pig ears into the US.