Salmonella Victim Bought Cantaloupe at Wal-Mart

Two Mississippi residents are among the 141 victims of this year’s cantaloupe-linked Salmonella Typhimurium outbreak. Only one of the Mississippians reported having consumed cantaloupe prior to becoming ill, according to Jim Newkirk of the Mississippi State Department of Health’s Office of Communications.

And that person purchased whole cantaloupe from Wal-Mart.

Bloomberg news reported on August 18th that Wal-Mart had withdrawn Indiana cantaloupes from its stores.

Neither of the two Mississippi outbreak victims was hospitalized, and no additional cases are currently under investigation in that state. The confirmed cases were reported from Rankin and Itawamba counties. Rankin County is east of Jackson, in the center of the state; Itawamba County is in Mississippi’s northeast corner.

As of August 17th, CDC reported that 141 outbreak cases of Salmonella Typhimurium had been documented in 20 US states. The agency expects to update those numbers later this week, according to CDC spokesperson Lola Russell.

While all of the 141 outbreak victims were infected with the same strain of Salmonella Typhimurium, only 75% (18 of 24) of those interviewed reported having consumed cantaloupe before becoming ill. Neither California victim was exposed to cantaloupe – or to other melons – and neither travelled to the hardest hit states (Kentucky, Indiana, Illinois). Only two of Iowa’s seven outbreak victims ate cantaloupe.

Ronald Owens of the California Department of Public Health offered this explanation when contacted by eFoodAlert:

It is not uncommon in these outbreak investigations to occasionally identify people who were infected by a similar strain of bacteria to the outbreak strain but who are considered “background” cases that are not related to an outbreak. The U.S. Centers for Disease Control and Prevention (CDC) estimates that there are about 10-15 background cases with this particular strain pattern that are detected each month.

This illustrates the difficulty faced by epidemiologists and public health officials in detecting and defining a foodborne disease outbreak that is caused by a relatively common genetic strain of bacteria. It’s far easier to recognize a needle in a haystack than to distinguish between two pieces of hay. In these circumstances, CDC defines an outbreak case as one that is a genetic match to the outbreak strain and falls within the outbreak timeframe.

Neither CDC nor FDA is yet prepared to identify the southwestern Indiana farm that is believed to be the source of the contaminated cantaloupes. No public recall has been announced.

CDC’s Advice to Consumers, Retailers and Others (as of August 17, 2012)

Contaminated cantaloupe may still be in grocery stores and in consumers’ homes.

Consumers who recently purchased cantaloupes grown in southwestern Indiana are advised not to eat them and discard any remaining cantaloupe.
- Based on the available information, consumers can continue to purchase and eat cantaloupes that did not originate in southwestern Indiana.
- Many cantaloupes have the growing area identified with a sticker on the fruit. If no sticker is present, consumers should inquire about the source. When in doubt, throw it out.
- Consumers who are buying or have recently bought cantaloupe should ask their retailer if the cantaloupe was grown in southwestern Indiana.
Cantaloupes should be disposed of in a closed plastic bag placed in a sealed trash can. This will prevent people or animals from eating them.
Dispose of any cantaloupes that you think may be contaminated. Washing them will not completely eliminate the contamination. Cutting, slicing and dicing may also transfer harmful bacteria from the fruit’s surface to the fruit’s flesh.
Retailers and food service operators should not sell or serve cantaloupe from southwestern Indiana.
Persons who think they might have become ill from eating possibly contaminated cantaloupes should consult their health care providers.

An Open Letter To The U.S. CDC

Last week, CDC released two “Final Update” reports on Salmonella outbreak investigations within a 48-hour period.

The first report, released on January 17th, summarized the results of an investigation into a 10-month long outbreak of Salmonella Typhimurium associated with exposure to clinical and teaching microbiology laboratories. The second report, released on January 19th, presented the results of an investigation into a 2-month long multi-state outbreak of Salmonella Enteritidis infections linked to a restaurant chain.

These two outbreaks had very little in common with each other; the outbreak settings were different, the scope and duration of the outbreaks were different, and the source of the infections was different. Nevertheless, the two outbreaks have one very important thing in common.

CDC, in conjunction with at least some of its public health partners at the state and local level, has chosen to withhold important information from the public.

What information has CDC withheld, and why should this information be released? Here is a list of questions that I sent to my media contact at CDC on January 18th, the day after the Salmonella Typhimurium outbreak report was released.

Is there a specific reason why CDC is not specifying the identity of the commercial strain of Salmonella Typhimurium that is associated with this outbreak (by the ATCC or NCTC strain number – not the commercial supplier)? Can you provide me with the strain number ID?
Does CDC have any hypothesis as to the trigger for this outbreak? Most of the commercial strains have been in use in various labs for many years. What may have happened to initiate the increase in cases? What determined the start date? With a baseline rate for the outbreak strain of 0 to 4 reports/week, how were the start and ending date established for this outbreak?
Were the outbreak cases all tied to the same commercial source of the S. Typhimurium “Strain X”?
Were the outbreak cases tied to the use of a specific format of the commercial source (for example, Bacti-discs or pre-filled inoculation loops)?
Have any cases involving this same strain been reported to CDC since the last “outbreak” case on June 29, 2011? If so, how has CDC differentiated those cases from the outbreak cases (keeping in mind the baseline of 0-4 cases per week mentioned in the CDC report).
Were the bulk of the cases linked to student labs or to clinical labs?

To these questions, I would now add, “Were the clinical lab cases tied mainly to in-hospital labs, or to free-standing commercial clinical labs? If the latter, was any single commercial lab chain disproportionately involved?”

When the Salmonella Enteritidis restaurant chain outbreak report hit the internet, I again contacted my CDC media liaison and asked, “Can you please explain why CDC has not revealed the name of the restaurant chain implicated in the above-mentioned outbreak? Even better, can you identify the chain by name?”

I realize that both outbreaks are “over” and that at least some of this information now is academic. Nevertheless, I question CDC’s actions in withholding information that could influence purchasing decisions on the part of consumers and of medical and lab professionals.

CDC reported on January 19th that Restaurant Chain A’s handling and cooking processes likely ruled out ground beef as a source of the Salmonella Enteritidis outbreak. This is favorable to the restaurant chain, and would give consumers comfort that the restaurants belonging to this fast food chain are following appropriate food-handling procedures – if only CDC had released the name of the chain.

As for the lab-related outbreak, if I was still running a microbiology lab, I would certainly want to know whether a specific packaging or format of commercially available control culture was more prone to contaminating the lab surroundings than others. I would opt to avoid this format, if I had the information and the choice. Likewise, as a medical doctor, I would opt to avoid a commercial clinical lab chain that was prone to in-lab contamination.

If either of these outbreaks had been traced to a specific packaged food, the offending food would have been named. There is no logical reason for restaurant-linked outbreaks to be handled differently. There is no logical reason for a lab-related outbreak to be handled differently.

I would appreciate receiving substantive answers to my questions.

Sincerely yours,

Phyllis Entis, MSc., SM(NRCM)
eFoodAlert

Hannaford Hamburger US Salmonella Outbreak – An Update

Updated December 22, 2011

On December 20th, CDC reported that 16 people in Hawaii (1), Kentucky (1), Massachusetts (1), Maine (4), New Hampshire (4), New York (4), and Vermont (1) have been infected with the relatively uncommon outbreak strain of Salmonella Typhimurium. Illnesses began on or after October 8, 2011, with the most recent illness onset reported on or about December 3rd.

Most of the illnesses are linked to the consumption of store-ground hamburger meat purchased from Hannaford supermarkets. Hannaford is a regional chain located in the northeast USA, with stores throughout Maine, Massachusetts, New Hampshire, New York and Vermont. The implicated ground beef packages were purchased between October 12th and November 20th.

Given the geographic location of Hannaford’s stores, it’s logical that the Northeastern states should bear the brunt of this outbreak. But what about the cases in Kentucky and Hawaii?

I checked with the departments of health for both states. Other than the genetic similarity between the strains of Salmonella Typhimurium recovered from outbreak patients, there is nothing that connects either the Hawaii or the Kentucky victim to this outbreak. Neither one reported traveling to the US Northeast prior to becoming ill. And, while the Kentucky case is still being investigated, neither victim reported any obvious link to the outbreak, such as consuming ground beef in the week before becoming ill.

Epidemiologists have nightmares like this!

Of course, the explanation may be very simple. PFGE, the genetic profiling used as a first stage “genetic fingerprint” in outbreak investigations is not infallible. CDC has been working with a second genetic profiling tool, which has, in some recent outbreaks, found that a few apparently connected illnesses actually were due to different strains of the same microbe. It’s also possible that some other common link will be found, or that the Kentucky and Hawaii cases will prove to be simply coincidental.

Regardless of the explanation for the Kentucky and Hawaii oddball cases, CDC offers the following reminders to consumers:

Consumers should check their homes, including their freezers, for recalled ground beef products and not eat them; restaurant and food service operators should not serve it. Consumers with questions about recalled ground beef products may contact Hannaford’s Customer Information Center, 8 a.m. to 8 p.m. at telephone number (800) 213-9040, and choose option 6.

Wash hands, kitchen work surfaces, and utensils with soap and water immediately after they have been in contact with raw meat or poultry, including frozen and fresh ground beef. Then, disinfect the food contact surfaces using a freshly prepared solution of 1 tablespoon unscented liquid chlorine bleach to 1 gallon of water.

Cook ground beef thoroughly. Ground beef dishes should always be cooked to 160°F internal temperature as measured with a food thermometer; leftovers also should be reheated to 160°F. The color of cooked ground beef is not an indicator that product has been safely cooked. Only by using a food thermometer can one accurately determine that ground beef has reached a safe minimum internal temperature of 160°F throughout the product. Ground beef can remain pink even after cooking to a safe minimum internal temperature of 160°F. Be particularly careful with foods prepared for infants, older adults, and persons with impaired immune systems. For more information, please visit FoodSafety.gov.

If served undercooked ground beef in a restaurant, send it back to the kitchen for further cooking.

Avoid cross-contaminating other foods. Uncooked meats and ground beef should be kept separate from produce, cooked foods, and ready-to-eat foods. Do not wash raw meat or poultry before cooking because splashing water can spread any pathogens present on raw meat surfaces to other kitchen surfaces. Hands, cutting boards, counters, knives, and other utensils should be washed thoroughly after touching uncooked foods. Hands should be washed before handling food, and between handling different food items.

Refrigerate raw and cooked meat and poultry within 2 hours after purchase (1 hour if temperatures exceed 90°F). Refrigerate cooked meat and poultry within 2 hours after cooking. Refrigerators should be set to maintain a temperature of 40°F or below.

Persons who think they might have become ill from eating possibly contaminated ground beef should consult their health care providers. Infants, older adults, and persons with impaired immune systems are more likely than others to develop severe illness.

Original Story (posted December 16, 2011)

Fourteen people in the US northeast have been infected with a strain of antibiotic-resistant Salmonella Typhimurium. Eleven of the 14 victims reported having eaten ground beef; in ten cases, the beef was purchased at a Hannaford store. Seven of the 14 victims (50%) were hospitalized.

Three illnesses were reported in New Hampshire. Other outbreak victims are from Maine (4), New York State (4) and Vermont (1). Three of the four New York State victims were among the seven who were hospitalized.

The outbreak has been traced epidemiologically to fresh in-store ground beef prepared in and purchased at Hannaford stores in Maine, New York, New Hampshire and Vermont between October 12 and November 20, 2011. The 85% ground beef was the most common variety associated with the outbreak.

Hannaford has recalled the following ground beef products (all package sizes) bearing Sell-by dates of Dec. 17, 2011 or earlier that were sold at the supermarket’s stores throughout Maine, Massachusetts, New Hampshire, New York and Vermont:

73% Hannaford Regular Ground Beef
75% Hannaford Regular Ground Beef
80% Hannaford Regular Ground Beef
85% Hannaford Regular Ground Beef
90% Hannaford Regular Ground Beef
80% Taste of Inspirations Angus Ground Beef
85% Taste of Inspirations Angus Ground Beef
90% Taste of Inspirations Angus Ground Beef
85% Nature’s Place Ground Beef
90% Nature’s Place Ground Beef

USDA’s Food Safety and Inspection Service (FSIS) has not been able to identify the suppliers who furnished Hannaford with the raw meat that was used to prepare the recalled ground beef, due to what the agency described as the retailer’s “limited records.” The possibility exists that raw beef contaminated with the Salmonella outbreak strain may also have been supplied to other retailers in the region.

Consumers who purchased ground beef from a Hannaford Supermarket should check their refrigerators and freezers for the recalled product. Hannaford is urging its customers to discard or return any packages of ground beef bearing a sell-by date of Dec. 17, 2011 or earlier. Anyone experiencing symptoms of salmonellosis should seek medical attention.

FSIS reminds consumers to “safely prepare their raw meat products, including fresh and frozen, and only consume ground beef that has been cooked to a temperature of 160° F.”