Outbreak strain of Salmonella found in dog food

Aug 28, 2007 (CIDRAP News) – Salmonella Schwarzengrund, a relatively rare serotype that has been reported in 64 recent human illness cases, was found recently in two samples of dog food made by a Tennessee company, according to the US Food and Drug Administration (FDA).

The finding prompted a recall of two products by Mars Petcare US, Inc., of Franklin, Tenn., the FDA said in an Aug 25 announcement. The company recalled 5-pound bags of Krasdale Gravy dry dog food sold in Connecticut, Massachusetts, New Jersey, New York, and Pennsylvania, and 50-pound bags of Red Flannel Large Breed Adult Formula dry food sold in Pennsylvania.

The FDA said people can be infected with Salmonella by handling contaminated pet food, especially if they don't wash their hands afterward. The agency said 64 human cases related to S Schwarzengrund have been reported to the Centers for Disease Control and Prevention (CDC), but none have been directly linked to the recalled products. The FDA and CDC are working with state and local officials to investigate the cases.

In an Aug 10 news release, the Pennsylvania Department of Health said it had found 21 S Schwarzengrund cases since January, many of them in infants or small children. "Most of the cases have occurred in households with pets or where people are in close contact with pets, but there is no evidence that any human consumed pet food," the statement said.

Ten dog food samples representing seven Mars Petcare products were tested by the FDA. The agency said it tested 10 subsamples from each sample, for a total of 150 tests, and found two that were contaminated—one Krasdale Gravy dry food and one Red Flannel Large Breed Adult Formula. The source of contamination was unknown, according to an FDA question-and-answer bulletin.

The recalled Krasdale Gravy bags have a UPC code of 7513062596 and "best by" dates of Jul 16 and 17, 2008; the Red Flannel bags have a UPC code of 42869000062 and a "best by" date of Jul 12, 2008. But the latter products were sold in only two stores in Pennsylvania, and only one bag was unaccounted for, the company said in an Aug 21 news release posted on the FDA Web site.

Schwarzengrund was the 29th most common Salmonella serotype among human cases reported to the CDC in 2005, according to information on the CDC Web site. It accounted for 138 cases, or 0.4% of the 36,184 cases that were serotyped.

Salmonella often causes fever, diarrhea (potentially bloody), nausea, vomiting, and abdominal pain in humans and can be serious or fatal in children, the elderly, and those with weakened immunity. In rare cases the pathogen can enter the bloodstream and cause severe disorders, such as infected aneurysms, endocarditis, and arthritis, the FDA said.

Pets infected with Salmonella may be lethargic and have diarrhea or bloody diarrhea, fever, and vomiting, but some will have only reduced appetite, fever, and abdominal pain, the agency said. Animals also can carry the pathogen without showing signs of illness.

The Pennsylvania news release listed several precautions for handling pet food. Among other things, it said pet owners should wash their hands before and after handling pet food, feed pets somewhere other than the kitchen, wash pet food dishes after each use (preferably not in the kitchen sink), and dispose of old or spoiled pet food safely.

Consumers with questions about the recalled products can call Mars Petcare at 866-298-8332, the FDA said.

See also:

Aug 25 FDA news release
http://www.fda.gov/NewsEvents/Newsroom/PressAnnouncements/2007/ucm108972.htm

Chart of 30 most common Salmonella serotypes from human cases reported to CDC in 2005
http://www.cdc.gov/ncidod/dbmd/phlisdata/salmtab/2005/SalmonellaTable1_2005.pdf

This week's top reads