Surge in Salmonella Enteritidis prompts egg recall

Aug 16, 2010 (CIDRAP News) – An outbreak of Salmonella infections has triggered a national recall of 13 shell egg brands and an extensive traceback investigation focused on an Iowa company that reportedly produced the eggs, the US Food and Drug Administration (FDA) said today.

In a recall notice posted by the FDA today, but dated Aug 13, Wright County Egg in Galt, Iowa, said it is recalling specific Julian dates of shell eggs because they may be contaminated with Salmonella. The eggs were distributed to food wholesalers, distribution centers, and foodservice companies in eight states: California, Illinois, Missouri, Colorado, Nebraska, Minnesota, Wisconsin, and Iowa.

Late this afternoon the US Centers for Disease Control and Prevention (CDC) announced that it, the FDA, and the US Department of Agriculture are investigating a fourfold national increase in the number of Salmonella Enteritidis (SE) isolates with the same pulsed-field gel electrophoresis (PFGE) pattern. In June and July about 200 isolates with that PFGE pattern, the most common in the PulseNet database, were submitted, compared with about 50 monthly uploads usually seen over the past 5 years. The CDC said many states have reported increases in the pattern since May.

The CDC said its investigators are conducting DNA analysis of the isolates to identify illnesses that may be part of the outbreak.

Epidemiologic investigations in California, Colorado, and Minnesota have revealed several possible case clusters that suggest shell eggs are a likely source of infections, the CDC said. Traceback investigations suggested that shell eggs from a single firm, Wright County Egg in Galt, Iowa, were consumed at many of the restaurants or events linked to the case clusters.

FDA officials are conducting an extensive investigation, including sampling and records review, of the Iowa company that produced the eggs, the CDC said.

Eggs subject to the recall were distributed nationally and were packaged under 13 different brand names: Lucerne, Albertson, Mountain Dairy, Ralph’s, Boomsma’s, Sunshine, Hillandale, Trafficanda, Farm Fresh, Shoreland, Lund, Dutch Farms, and Kemps. The eggs are packaged in different sized cartons, including 6-egg, dozen, and 18-egg cartons. Recalled eggs have Julian dates that range from 136 to 225 with the plant numbers 1026, 1413, and 1946. Dates and codes are stamped on the end of an egg carton. The stamp begins with the letter P, followed by a space and then the Julian date. (The Julian calendar numbers days consecutively throughout the year rather than by month.)

The recall notice said SE illnesses have been linked to the shell eggs, but did not give any details about how many illnesses have been reported or how many states have been affected.

The recall notice contained little information about the company, referring media calls to the Egg Safety Center, based in Alpharetta, Ga. It reminded consumers that eggs should be properly stored, handled, and fully cooked to avoid foodborne illnesses.

The group said SE is rare in the United States, especially since US egg farmers have adopted stricter food safety measures, such as more modern, sanitary poultry housing systems, biosecurity and pest-control measures, inoculation against SE, and testing.

Dr Shaun Cosgrove, an epidemiologist with the Colorado Department of Public Health and Environment, told CIDRAP News that one of the first clues in the SE outbreak surfaced when health officials in Jefferson County responded to a relatively large outbreak involving the strain. "That pattern is common year round, and it's not as simple as detecting clusters when you already see a baseline," he said.

According to an Aug 4 Jefferson County Public Health statement, 28 people who ate at a locally owned restaurant called The Fort between Jul 10 and Jul 16 got sick. SE was confirmed in 8 of the cases and suspected in 20. County officials said they were investigating menu items that contained undercooked or potentially undercooked egg products.

Cosgrove said investigators suspected a raw egg product that was used as a final dressing on one of the menu items. When Colorado lab officials tested the menu item and its components, one of the components that contained eggs tested positive for the outbreak strain, he said.

About that time, he said Colorado authorities became aware of a national increase in the same SE PFGE pattern. Cosgrove said shortly afterward he spoke with a colleague from California during a meeting of the International Association for Food Protection in Anaheim who had identified a handful of SE clusters at restaurants. Minnesota public health officials had also detected similar clusters, and Cosgrove said an investigation found that all egg products with links to the clusters in the three states came from the same farm in Iowa.

The Minnesota Department of Health (MDH) said today in a statement that it has so far linked seven illnesses to the multistate egg recall. It said the SE cases were identified in two restaurant outbreaks in May and July in which eggs were identified as the likely food vehicle. Health officials warned that many more cases could be involved. Dr Kirk Smith, foodborne illness supervisor with the MDH, said in the statement that SE is one of the most common circulating Salmonella strains, and he estimated that for every confirmed case, there are 38 more unconfirmed cases.

On Jul 9, new federal rules aimed at reducing SE contamination in eggs took effect, and the FDA predicted the tougher measures will prevent up to 79,000 illnesses per year. The regulations took several years to develop and target operations that have more than 50,000 laying hens, which covers about 80% of the US egg market. Details about the size of Wright County Eggs' Galt, Iowa, facility were not immediately available. Galt is located in north central Iowa. Iowa is the nation's top producer of eggs, averaging about 53,500,000 layers, according to United Egg Producers, an industry group.

Some food safety experts have hailed the new shell egg safety rules as a solid set of guidelines, but have warned that the rules won't eliminate the risk and that not all SE cases are related to eggs. The new rules require companies to refrigerate eggs during transportation and storage. Under the new rule, the FDA said, large producers who don't use a treatment such as pasteurization must:

  • Buy chicks and hens only from suppliers who monitor their birds for Salmonella Establish rodent- and pest-control measures and biosecurity measures to prevent people and equipment from spreading bacteria
  • Test for SE in their poultry houses and, if it is found, follow up with biweekly testing of eggs for 8 weeks. If any of the tests are positive, the eggs must be further processed to destroy bacteria or diverted to nonfood use.
  • Clean and disinfect poultry houses that test positive for SE
  • Refrigerate eggs at 45ºF during storage and transportation, starting no later than 36 hours after they are laid. This requirement also applies to producers who use pasteurization and to those who transport or hold eggs.

Egg producers who have between 3,000 and 50,000 laying hens will be subject to the new rules in 2 years, and those with 3,000 or fewer birds or sell their products directly to consumers are exempt from the rules.

See also:

Aug 13 recall notice

Aug 16 CDC statement

Aug 4 Jefferson County Public Health press release

Aug 16 Minnesota Department of Health press release

Jul 9 CIDRAP News story "Rules to limit Salmonella in eggs take effect"

United Egg Producers background information

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