Nov 6, 2008 (CIDRAP News) Salmonella infections associated with dry pet food from a plant in Pennsylvania have continued to crop up in recent months, prompting closure of the plant and concern that contaminated products may still be in use, the Centers for Disease Control and Prevention (CDC) reported today.
Eight more cases of infection with the outbreak strain of Salmonella enterica serotype Schwarzengrund, a fairly rare type, have been identified this year, raising the total to 79 cases since 2006, the CDC said today in the Nov 7 issue of Morbidity and Mortality Weekly Report.
The continued emergence of cases linked to pet food from a Mars Petcare US facility in Everson, Pa., led the company to issue a nationwide recall in September and to announce on Oct 1 that the plant would be closed permanently, the report says.
In 2006 and 2007 the CDC, the Food and Drug Administration (FDA), and several state health departments found a series of S Schwarzengrund infections involving matching DNA fingerprints. In August 2007, after the FDA found the same strain in two Mars Petcare product samples, the company announced a recall of some products made at the Everson facility. The plant was closed for cleaning and renovation from July until mid-November of 2007.
In May of this year, the CDC reported that 70 cases of infection with the outbreak strain had been identified in 19 states in 2006 and 2007, marking the first known human salmonellosis outbreak linked to dry pet food.
Despite the recall and the plant cleanup, more cases involving the outbreak strain have been found since April of this year, with the latest one identified Sep 18, the CDC said. The eight cases included three in Pennsylvania, two in Georgia, two in New York, and one in Texas. Six of the patients were 2 years old or younger. One patient was hospitalized, but there were no deaths.
Six of the eight patients' households had pets (pet ownership status for the other two was not known), but none of the pets had been sick, the CDC reported. Three households used brands of pet food made at the Everson plant, but it could not be determined whether any of the food had actually come from that plant.
In August of this year, the FDA found the outbreak strain of Salmonella in "multiple brands" of products at the Everson plant. This prompted the company to announce on Sep 12 a recall of all dry dog and cat food products made at the plant from Feb 18 through Jul 29, amounting to more than 23,000 tons, according to the CDC. On Oct 1 the firm said the plant would be closed permanently.
"The original source of contamination and mechanisms for continued contamination in the Everson plant over a 3-year period are unknown," the article states. The FDA is working with the company on a continuing investigation.
The CDC warned that the outbreak may not be over, since dry pet food has a shelf life of 1 year and contaminated products may still be in people's homes. The agency also noted that Salmonella contamination has triggered at least 13 recalls involving pet products made in various facilities since 2006, though no human cases have been associated with products other than those from the Mars Petcare factory.
Dog and cat foods made at the Everson plant were sold under many different brand names, including Pedigree, Country Acres, Members Mark, Ol' Roy, Paws & Claws, Pet Pride, PMI Nutrition, Red Flannel, Retriever, and Wegman's, according to Mars Petcare's Sep 12 recall notice. The notice includes a large chart of the products included in the recall.
Many of the brands are national brands that are made at multiple factories, the company said. For brands other than Pedigree, products made at the Everson facility are identified by the number 17 as the first two digits of the production lot code, found on the back of the bag, just after the "best before" date. For Pedigree products, consumers should look for the letters "PAE" as the sixth, seventh, and eighth characters in the production code, found after the "best before" date, the company said.
Consumers and health departments should be aware that all dry pet food, pet treats, and pet supplements could be contaminated with pathogens such as Salmonella, the CDC said. People should wash their hands with water and soap for at least 20 seconds after handling these products, and especially before handling human food. Children under age 5 should not be allowed to touch or eat dry pet food.
Canned pet food is unlikely to be tainted, as the manufacturing process should eliminate any bacterial contamination, the agency said.
CDC. Update: Recall of dry dog and cat food products associated with human Salmonella Schwarzengrund infectionsUnited States, 2008. MMWR 2008 Nov 7;57(44):1200-2 [Full text]
May 16 CIDRAP News story "CDC warns of Salmonella risk from dry pet food"
Aug 28, 2007, CIDRAP News story "Outbreak strain of Salmonella found in dog food"