Pathogenic Serotypes of E. coli Causes Food-Recalls

Aug 27

Who would have thought that the food manufacturing business could be quite a delicate undertaking? When a food manufacturer has some mishaps leading to product contamination; the consumer’s health is often negatively affected. In essence, the food manufacturing business entails heavy responsibilities and one of their responsibilities includes protecting the public from pathogens such as E. coli.

This heavy responsibility was exhibited last August 6 when ‘Taylor Farms’ products were recalled in several American states over concerns of a possible Salmonella outbreak. At the time of writing, no one is infected yet but the public is advised to be wary of the following products Taylor Farms Macaroni Salad, Taylor Farms Rotini Pasta Salad, Taylor Farms Chicken Salad Croissant, Marketside Diced Yellow Onion, Marketside Diced Mirepoix, and Marketside Fajita Stir Fry.1

For more information on the lot codes of the recalled products visit the U.S. Food and drug administration website.

What are food-recalls in the first place?

Food-recalls happens when a food producer would issue an announcement to take back and temporarily cease the sale of their products over health concerns. Sometimes food manufacturers are unable to detect unintentional contamination of their products that people would get ill. In cases like these, the government may notice the blunder first and issue an order to the food manufacturer to perform food-recalls. There are various reasons as to why food-recalls would occur; detection of pathogenic microbes, the discovery of harmful foreign objects such as toxic metals and broken glass, and the detection of unforeseen allergens. For this particular article, we are focusing on pathogenic microbes specifically the pathogenic serotypes of Escherichia coli.2

Wait, I thought E. coli is harmless?

Technically, Escherichia coli is harmless save for cases when they wind up in places where they shouldn’t be, such as in open wounds, leading to opportunistic infections. They are natural inhabitants of the colon of humans and warm-blooded animals. However, there are certain Escherichia coli bacteria that have undergone mutations, referred to as serotypes, which made them pathogenic. Infection with these bacteria often occurs through the fecal-oral route or through the consumption of food that is contaminated with fecal matter containing the bacteria.3

Several outbreaks of the pathogenic serotypes of E. coli have been documented. The causes of these outbreaks include contamination of fruits and vegetables like sprouts, spinach, salad, and coleslaw, with fecal matter during the cultivation process or through handling, contamination of drinking water, and contamination of recreational water.3

Pathogenic E. coli strains reported to have caused outbreaks

The E. coli serotype that has caused a lot of outbreaks is the E. coli O157 H7. This is also the most common Shiga toxin-producing Escherichia coli. Cases of hemolytic uremic syndrome and hemorrhagic colitis are often associated with these bacteria. It is important to note that this is not the only Shiga toxin-producing Escherichia coli there are other serotypes that are less common in the United States but quite significant in other countries.4

E. coli O103 Is another Shiga Toxin-producing E. coli or STEC. Infection with this bacteria would lead to symptoms that are indistinguishable with that of E. coli O157 H7. It was first isolated in Japan in 2001.5

Some serotypes of E. coli may belong to more than one classification. In the case of E. coli O121, it is classified as enterohemorrhagic, which means it causes hemorrhagic colitis, and it is also classified as enteroinvasive. Furthermore, there are cases wherein the aforementioned bacteria caused shigellosis like illness.6

E. coli O26 is a STEC. Infection with the bacteria would still cause diarrhea and hemorrhagic colitis, but most of the time it does not lead to hemolytic uremic syndrome. Most people that are infected with E. coli O26 recover quickly and only a few people would develop a severe form of the infection.7

E. coli O145 is another Shiga Toxin-producing E. Coli that is completely indistinguishable from E. coli O157 H7. The only difference is that E. coli O145 can ferment sorbitol while E. coli O157 H7 cannot. When E. coli O145 is grown in a sorbitol MacCongkey it will have pink-colored colonies while E. coli O157 H7 would have colorless colonies.8,9

Yet another case of an E. coli serotype falling under two classifications was reported in 2011. After some rigorous genetic analysis on E. coli O104, the bacteria that caused an outbreak of hemolytic diarrhea in Europe, it was found out that this bacteria belonged to enteroaggregative and enterohemorrhagic classification.10

E. coli outbreaks which prompted food-recalls

The Center for Disease Control has kept a record of all known outbreaks of pathogenic E. coli serotypes starting from 2006.11 In this year, two E. coli O157 H7 outbreaks were recorded. The first outbreak was traced back to Taco Bell’s shredded lettuce. While in the second outbreak E. coli O157 H7 was isolated from 13 packages of spinach that were supplied to 10 states. In all cases of E. coli outbreaks in which food was the source of infection, the food’s manufacturer had to issue a recall per-protocol.12,13

In the following year, Two more outbreaks of E. coli O157 H7 occurred. The source of infection for the first outbreak was the frozen pizza manufactured and sold by the General Mills Company. The second outbreak was traced back to frozen ground beef patties which prompted the food manufacturers to recall a total of 21.7 million pounds of the food item.14,15

From 2008 to 2009, four outbreaks of E. coli O157 H7 occurred. Ground beef purchased at Kroger® retail stores was the source of infection in the 2008 outbreak. Nestle Toll House’s refrigerated cookie dough was the source of infection in the first 2009 outbreak. This was followed by a food-recall of more than 400,000 pounds of beef patty which were produced by the JBS Swift Beef Company as E. coli O157 H7 was isolated in the recalled food items. A few months later, USDA Food Safety and Inspection Service had Fairbank Farms recall a total of 545,699 pounds of ground beef products. At the end of the year, the USDA Food Safety and Inspection Service issued another food recall but this time it was directed to National Steak and Poultry. The food manufacturer was ordered to recall 248,000 pounds of beef products.16,17,18,19,22

In 2010 yet another outbreak of E. coli O157 H7 occurred with Bravo Farms’ Dutch Style Gouda Cheese being the source of infection. It is in this year that the Center for Disease Control recorded its first case of E. coli O145 outbreak. The source of infection was traced back to contaminated shredded romaine lettuces. Two years later, a second outbreak would occur.20,21,28

In the following year, the US saw its first case of E. coli O104 H4 infections. However, the outbreak did not occur within the country. Instead, those who were infected caught the disease from Germany. The European Food Safety Authority has pinpointed the source of the infection to sprouts grown in France but whose seeds were exported from Egypt. As always, safety protocols prohibited the sale and consumption of the sprouts. This E. coli serotype was especially dangerous as it is both Enterohemorrhagic and Enteroaggregative. Meaning it can cause bloody diarrhea, hemolytic uremic syndrome and can cause mutations in the cells of the gastrointestinal tract which leads to abnormal cell fusion. Approximately 900 people in Germany died because of this E. coli serotype.24,

Aside from the E. coli O104 H4 infections, three outbreaks of E. coli O157 H7 were also recorded in 2011. Romaine lettuce was the source of the infectious agent in the first one. The second outbreak resulted in a massive recall of 23,000 pounds of Lebanon bologna products produced by the Palmyra Bologna Company. In the third outbreak, DeFranco & Sons company voluntarily recalled bulk and consumer-packaged in-shell hazelnuts and mixed-nut products containing hazelnuts.23,25,26

In 2012, the State Garden of Chelsea had to recall their pre-packaged green leafy vegetables due to E. coli O157 H7 contamination which was attributed to a multistate outbreak. The first outbreak of Shiga-toxin-producing E.coli O26 was reported in this year, affecting a total of 29 persons. Public health agencies traced the source of infection to Jimmy John’s restaurants, specifically their raw clover sprouts.27,29

35 individuals spread over several states were the first reported cases of E. coli O121 infection in the United States. These cases were reported in 2013 and led to recalls of Farm Rich Brand’s frozen food products. There may never be a year wherein outbreaks of E. coli O157 H7 does not occur. 33 people were infected this year because they ate Glass Onion Catering’s Field Fresh Chopped Salad with Grilled Chicken and or Mexicali Salad with Chili Lime Chicken.31 ,30

From 2012 onwards, the same E. coli serotypes kept on popping up and causing outbreaks. But in 2019 and 2020, a new E. coli serotype has appeared, the E. coli O103. In 2019, the bacteria caused an outbreak twice. The first outbreak resulted in the recall of Northfork Bison Distributions Incorporated’s ground bison and Bison Burgers and/or Buffalo Burgers. In the second outbreak, K2D Foods recalled approximately 113,424 pounds of raw ground beef products. A year after, Chicago Indoor Garden recalled all products containing red clover sprouts because 51 individuals were infected with E. coli O103 because of them.32,33,34

In all cases, the food manufacturers followed protocol and issued food-recalls when they were ordered to do so. Aside from this, the manufacturers followed food safety and handling protocols. This just goes to show that mishaps would still happen no matter how careful a manufacturer is.

What to do with a recalled product

So if you have, in your possession, a food product that has been recalled due to germ contamination the main concern would be to avoid ingesting the contaminant. If you haven’t opened the product yet then you could just dispose of it or if the manufacturers ask for the return of their products you could do it following their instructions. However, if you have opened the product and had it come into contact with utensils, cookware, or kitchen appliances then you have to consider cleaning these items. Clean whatever object that came into contact with the product with warm soapy water. Then wipe them with a cloth that contains diluted bleach; 1 tablespoon bleach mixed with 1 gallon of distilled water.2

Symptoms that you should look out for

All of the E. coli serotypes that have been mentioned are Shiga Toxin-producing E. Coli so infection with any one of them is bound to cause similar symptoms. Mild cases of STEC infection would present with abdominal cramps and diarrhea. A more serious case would involve bloody diarrhea, fever, and vomiting. Although rare, there are cases wherein the disease would progress to hemolytic uremic syndrome which is a life-threatening condition. Bottom line is, whenever you would experience bloody diarrhea and or severe abdominal cramps, you should go visit a physician immediately.3