Cantaloupes are available in supermarkets all year round, but may be scarce and more expensive in the winter. Peak cantaloupe season is from June to October.

And, here we are in November.

In this most current Salmonella outbreak linked to Mexican grown cantaloupe, all the illnesses in the United States and Canada have occurred from mid-October to min-November.

Salmonella is an organism which can cause serious and sometimes fatal infections in young children, frail or elderly people, and others with weakened immune systems. Healthy persons infected with Salmonella often experience fever, diarrhea (which may be bloody), nausea, vomiting and abdominal pain. In rare circumstances, infection with Salmonella can result in the organism getting into the bloodstream and producing more severe illnesses such as arterial infections (i.e., infected aneurysms), endocarditis and arthritis.

The U.S. and Canadian Salmonella Cantaloupe Outbreaks: 

As of November 24, 99 people infected with the outbreak strain of Salmonella have been reported from 32 states. Arkansas (1), Arizona (7), California (1), Colorado (2), Georgia (3), Iowa (5), Illinois (4), Indiana (2), Kentucky (5), Massachusetts (1), Maryland (1), Michigan (1), Minnesota (13), Missouri (9), Mississippi (1), North Carolina (2), Nebraska (4), New Jersey (1), Nevada (2), New York (1), Ohio (8), Oklahoma (1), Oregon (1), Pennsylvania (1), Rhode Island (1), South Carolina (3), Tennessee (4), Texas (3), Utah (1), Virginia (1), Washington (1) and Wisconsin (8). Illnesses started on dates ranging from October 17, 2023, to November 10, 2023. Of 77 people with information available, 45 have been hospitalized. Two deaths have been reported from Minnesota.  Age of ill ranges from less than 1 to 100 years of age.  60% are male and 40% are female.

As of November 24, there have been 63 laboratory-confirmed cases of Salmonella Soahanina, Sundsvall and Oranienburg illness linked to this outbreak in the following provinces: British Columbia (12), Ontario (12), Quebec (35), Prince Edward Island (2) and Newfoundland and Labrador (2). Additional Salmonella infections are under investigation and more illnesses associated with this outbreak may be confirmed. Individuals became sick between mid-October and mid-November 2023. Seventeen individuals have been hospitalized. One death has been reported. Individuals who became ill are between 0 to 100 years of age. About half of the cases (51%) are male.

William “Bill” Marler has been a food safety lawyer and advocate since the 1993 Jack-in-the-Box E. coli Outbreak which was chronicled in the book, “Poisoned” and in the recent Netflix documentary by the same name. Bill work has been profiled in the New Yorker, “A Bug in the System;” the Seattle Times, “30 years after the deadly E. colioutbreak, A Seattle attorney still fights for food safety;” the Washington Post, “He helped make burgers safer, Now he is fighting food poisoning again;” and several others.. Dozens of times a year Bill speaks to industry and government throughout the United States, Canada, Europe, Africa, China and Australia on why it is important to prevent foodborne illnesses.  He is also a frequent commentator on food litigation and food safety on Marler Blog. Bill is also the publisher of Food Safety News.

Marler Clark has been in the middle and in the lead for all the Salmonella Cantaloupe Outbreaks over the last decades. Here is a sampling:

At least 162 sickened, 62 hospitalized with 3 deaths.

Bill Marler, food safety advocate and foodborne illness attorney since 1993, whose Seattle law firm, Marler Clark’s work was recently profiled in the Netflix documentary “Poisoned,” The Dirty Truth about your Food, is calling on the importers of Salmonella-tainted cantaloupes to pay the medical bills of the victims of the outbreak in the United States and Canada.

Retailers and wholesalers have recalled cantaloupes from Crown Jewels Produce in boxes labeled “Malachita/Z Farms” or from Sofia Produce doing business as TruFresh in boxes labeled “Malichita” or “Rudy”, or from Pacific Trellis in corrugated cartons with certain lot codes.

In the United States as of November 24, 99 people infected with the outbreak strain of Salmonella Sundsvall have been reported from 32 states. Arkansas (1), Arizona (7), California (1), Colorado (2), Georgia (3), Iowa (5), Illinois (4), Indiana (2), Kentucky (5), Massachusetts (1), Maryland (1), Michigan (1), Minnesota (13), Missouri (9), Mississippi (1), North Carolina (2), Nebraska (4), New Jersey (1), Nevada (2), New York (1), Ohio (8), Oklahoma (1), Oregon (1), Pennsylvania (1), Rhode Island (1), South Carolina (3), Tennessee (4), Texas (3), Utah (1), Virginia (1), Washington (1) and Wisconsin (8). Illnesses started on dates ranging from October 17, 2023, to November 10, 2023. Of 77 people with information available, 45 have been hospitalized. Two deaths have been reported from Minnesota.  Age of ill ranges from less than 1 to 100 years of age. 

In Canada as of November 24, there have been 63 laboratory-confirmed cases of Salmonella Soahanina, Sundsvall and Oranienburg illness linked to this outbreak in the following provinces: British Columbia (12), Ontario (12), Quebec (35), Prince Edward Island (2) and Newfoundland and Labrador (2).  Individuals became sick between mid-October and mid-November 2023. Seventeen individuals have been hospitalized. One death has been reported. Individuals who became ill are between 0 to 100 years of age.

“Unfortunately, those numbers will likely rise in the coming week,”  Marler said. “The cost of treating victims of Salmonella infections can run in the tens of thousands of dollars, or in a severe case, even in the hundreds of thousands of dollars. These families need these companies to do more than promise to cooperate in the investigation into this outbreak. They need to know that these companies intend to fulfill their corporate responsibility by looking out for their customers,” added Marler.

Marler noted that over the last two decades in other outbreak-situations, companies such as Chi-Chi’s, Dole, Jack in the Box, Conagra, Odwalla and Sheetz advanced medical costs for outbreak victims whose illnesses were traced to their food products.

William “Bill” Marler has been a food safety lawyer and advocate since the 1993 Jack-in-the-Box E. coli Outbreak which was chronicled in the book, “Poisoned” and in the recent Netflix documentary by the same name. Bill work has been profiled in the New Yorker, “A Bug in the System;” the Seattle Times, “30 years after the deadly E. coli outbreak, A Seattle attorney still fights for food safety;” the Washington Post, “He helped make burgers safer, Now he is fighting food poisoning again;” and several others.. Dozens of times a year Bill speaks to industry and government throughout the United States, Canada, Europe, Africa, China and Australia on why it is important to prevent foodborne illnesses.  He is also a frequent commentator on food litigation and food safety on Marler Blog. Bill is also the publisher of Food Safety News.

Marler Clark has been in the middle and in the lead for all the Cantaloupe Outbreaks over the last decades. Here is a sampling:

See the trailer and watch the documentary.

The U.S. and Canadian Salmonella Cantaloupe Outbreaks: 

As of November 24, 99 people infected with the outbreak strain of Salmonella have been reported from 32 states. Arkansas (1), Arizona (7), California (1), Colorado (2), Georgia (3), Iowa (5), Illinois (4), Indiana (2), Kentucky (5), Massachusetts (1), Maryland (1), Michigan (1), Minnesota (13), Missouri (9), Mississippi (1), North Carolina (2), Nebraska (4), New Jersey (1), Nevada (2), New York (1), Ohio (8), Oklahoma (1), Oregon (1), Pennsylvania (1), Rhode Island (1), South Carolina (3), Tennessee (4), Texas (3), Utah (1), Virginia (1), Washington (1) and Wisconsin (8). Illnesses started on dates ranging from October 17, 2023, to November 10, 2023. Of 77 people with information available, 45 have been hospitalized. Two deaths have been reported from Minnesota.  Age of ill ranges from less than 1 to 100 years of age.  60% are male and 40% are female.

As of November 24, there have been 63 laboratory-confirmed cases of Salmonella Soahanina, Sundsvall and Oranienburg illness linked to this outbreak in the following provinces: British Columbia (12), Ontario (12), Quebec (35), Prince Edward Island (2) and Newfoundland and Labrador (2). Additional Salmonella infections are under investigation and more illnesses associated with this outbreak may be confirmed. Individuals became sick between mid-October and mid-November 2023. Seventeen individuals have been hospitalized. One death has been reported. Individuals who became ill are between 0 to 100 years of age. About half of the cases (51%) are male.

What Cantaloupe to Avoid Products and Stores in the U.S. Affected (Expanded and Updated on 11/27/2023)

  • Whole fresh cantaloupes with a label on the cantaloupe that says “Malichita” or “Rudy”, “4050”, and “Product of Mexico/produit du Mexique”.
  • Retailers and wholesalers would have received recalled whole melons from Crown Jewels Produce in boxes labeled “Malachita/Z Farms” or from Sofia Produce doing business as TruFresh in boxes labeled “Malichita” or “Rudy”, or from Pacific Trellis in corrugated cartons with certain lot codes.
  • ALDI cantaloupe, cut cantaloupe, and pineapple spears in clamshell packaging with Best-by dates between October 27 and October 31.
  • Vinyard cantaloupe chunks and cubes, fruit mixes, melon medleys, and fruit cups containing cantaloupe. Most have a “Vinyard” label, and some have a red label with “Fresh” sold between October 30 and November 10 in Oklahoma stores.
  • Freshness Guaranteed seasonal blend, melon trio, melon mix, fruit blend, fruit bowl, seasonal fruit tray, fruit mix, and cantaloupe chunks; and RaceTrac fruit medley sold in clear square or round plastic containers at select retail stores in IN, MI, OH, KY, NC, TN, VA, IL, TX, LA (see recall announcement for lot codes and “best by” dates).

Past Cantaloupe Outbreaks and Lawsuits

Marler Clark has been in the middle and in the lead for all the Cantaloupe Outbreaks Lawsuits over the last decades. Here is a sampling:

salmonella2_300

As of November 24, 99 people infected with the outbreak strain of Salmonella have been reported from 32 states. Arkansas (1), Arizona (7), California (1), Colorado (2), Georgia (3), Iowa (5), Illinois (4), Indiana (2), Kentucky (5), Massachusetts (1), Maryland (1), Michigan (1), Minnesota (13), Missouri (9), Mississippi (1), North Carolina (2), Nebraska (4), New Jersey (1), Nevada (2), New York (1), Ohio (8), Oklahoma (1), Oregon (1), Pennsylvania (1), Rhode Island (1), South Carolina (3), Tennessee (4), Texas (3), Utah (1), Virginia (1), Washington (1) and Wisconsin (8).

Illnesses started on dates ranging from October 17, 2023, to November 10, 2023.

Of 77 people with information available, 45 have been hospitalized. Two deaths have been reported from Minnesota.

Public health officials collect many different types of information from sick people, including their age, race, ethnicity, other demographics, and the foods they ate in the week before they got sick. This information provides clues to help investigators identify the source of the outbreak.  Age of ill ranges from less than 1 to 100 years of age.  60% are male and 40% are female.

As of November 24, there have been 63 laboratory-confirmed cases of Salmonella Soahanina, Sundsvall and Oranienburg illness linked to this outbreak in the following provinces: British Columbia (12), Ontario (12), Quebec (35), Prince Edward Island (2) and Newfoundland and Labrador (2). Additional Salmonella infections are under investigation and more illnesses associated with this outbreak may be confirmed. Individuals became sick between mid-October and mid-November 2023. Seventeen individuals have been hospitalized. One death has been reported. Individuals who became ill are between 0 to 100 years of age. About half of the cases (51%) are male.

CFIA issued food recall warnings on November 1, November 14 and November 17 for Malichita brand cantaloupes sold between October 11 and November 14, 2023. On November 24, 2023, CFIA updated the food recall warning to also include Rudy brand cantaloupes sold between October 10 and November 24, 2023. Additional secondary recalls have been issued for products that were made using recalled cantaloupes and for produce items that were processed alongside recalled cantaloupes. 

Through the CFIA investigation the outbreak strains of Salmonella that made people sick were found in samples of the recalled Malichita brand cantaloupe.

More recent illnesses may be reported in the outbreak because there is a period between when a person becomes ill and when the illness is reported to public health officials. For this outbreak, the illness reporting period is between 2 and 4 weeks.

illustration-of-structure-of-salmonella-b-john-bavosi

Canada is reporting 26 ill in British Columbia 7, Ontario 7, Quebec 8, Prince Edward Island 2, Newfoundland and Labrador 2.

In the United States since the last update on November 17, 2023, 56 more illnesses have been reported. As of November 24, 99 people infected with the outbreak strain of Salmonella have been reported from 32 states. Arkansas 1, Arizona 7, California 1, Colorado 2, Georgia 3, Iowa 5, Illinois 4, Indiana 2, Kentucky 5, Massachusetts 1, Maryland 1, Michigan 1, Minnesota 13, Missouri 9, Mississippi 1, North Carolina 2, Nebraska 4, New Jersey 1, Nevada 2, New York 1, Ohio 8, Oklahoma 1, Oregon 1, Pennsylvania 1, Rhode Island 1, South Carolina 3, Tennessee 4, Texas 3, Utah 1, Virginia 1, Washington 1 and Wisconsin 8.

Illnesses started on dates ranging from October 17, 2023, to November 10, 2023.

Of 77 people with information available, 45 have been hospitalized. Two deaths have been reported from Minnesota.

Public health officials collect many different types of information from sick people, including their age, race, ethnicity, other demographics, and the foods they ate in the week before they got sick. This information provides clues to help investigators identify the source of the outbreak.  Age of ill ranges from less than 1 to 100 years of age.  60% are male and 40% are female.

State and local public health officials are interviewing people about the foods they ate in the week before they got sick. Of the 33 people interviewed, 29 (88%) reported eating cantaloupe. 

Recalled whole cantaloupe from the following brands:

  • Whole fresh cantaloupes with a label on the cantaloupe that says “Malichita” or “Rudy”, “4050”, and “Product of Mexico/produit du Mexique”
  • Cantaloupe was sold at retail stores in AZ, CA, MD, NJ, TN, IL, IN, KY, MI, OH, OK, WI, TX, FL, and Canada. This list may not include all states as the cantaloupes could have reached consumers through further retail distribution.
  • Retailers and wholesalers would have received recalled whole melons from Crown Jewels Produce in boxes labeled “Malachita/Z Farms” or from Sofia Produce doing business as TruFresh in boxes labeled “Malichita” or “Rudy.”

Recalled cut cantaloupe and products made from recalled whole cantaloupes:

  • ALDI cantaloupe, cut cantaloupe, and pineapple spears in clamshell packaging with Best-by dates between October 27 and October 31.
  • Vinyard cantaloupe chunks and cubes, fruit mixes, melon medleys, and fruit cups containing cantaloupe. Most have a “Vinyard” label, and some have a red label with “Fresh” sold between October 30 and November 10 in Oklahoma stores.
  • Freshness Guaranteed seasonal blend, melon trio, melon mix, fruit blend, fruit bowl, seasonal fruit tray, fruit mix, and cantaloupe chunks; and RaceTrac fruit medley sold in clear square or round plastic containers at select retail stores in IN, MI, OH, KY, NC, TN, VA, IL, TX, LA (see recall announcement for lot codes and “best by” dates).

CDC is advising people not to eat, sell, or serve recalled fruit.

Cantaloupe

The use of good cleaning and sanitizing practices is crucial during production and distribution of fresh fruits and vegetables to reduce the risk of microbial contamination. The implementation of such practices is standard in most production facilities because soil, compost, water, personnel, and/or harvesting/processing equipment can all be sources of harmful microbes that could result in a foodborne illness.

Outbreaks associated with the consumption of cantaloupes contaminated with the bacteria Salmonella Typhimurium and Listeria monocytogenes have occurred in recent years. The U.S. Food and Drug Administration (FDA) put together guidelines to advise consumers to clean cantaloupe before eating. These recommendations include: 

1) examining for visible damages on the surface of cantaloupe, 

2) washing cantaloupe under running water with a brush, 

3) using clean utensils and cutting boards to avoid cross contamination, and 

4) keeping cantaloupe below 40°F.

What is the difference between cleaning and sanitizing?

Cleaning refers to the removal of soil or any other visible contaminants from the surface of the

object. Sanitizing is the process of removing the contaminants not visible to the naked eye (for example, bacteria). The latter is an excellent complement to the cleaning step of the food commodity, and commonly involves the use of a chemical to reduce the number of microbes that could still be associated with a surface, fruit, and/or vegetable after cleaning. 

Examples of sanitizers that consumers can use on cantaloupes and other fresh produce include unscented household bleach and hydrogen peroxide, vinegar, iodine, and hot water. The washing and sanitizing process for fresh produce recommended by the FDA involves washing and scrubbing to remove the dirt and microbes (FDA, 2018). To increase the removal of possible microbial contaminants, the washed produce is then soaked in a diluted solution of the sanitizer for a given period (typically around 5 minutes). Consumers should be aware that shortening the recommended time of exposure to a sanitizer may reduce how well the sanitizer can kill any bacteria that are present.

Hot water as a sanitizer

As an alternative to chemical sanitizers, consumers can use hot water. This is commonly used as a sanitizer in food facilities and restaurants to sanitize equipment, dishes, and other utensils. The U.S. Department of Agriculture (USDA) recommends a minimum temperature of 180°F for sanitation purposes. Hot water sanitizing is very practical because it is easy to obtain, apply, and remove, in comparison to chemical alternatives. Previous research in our laboratory has shown the efficacy of hot water to reduce Listeria monocytogenes and Salmonella Typhimurium in cantaloupe. Water temperature must be kept at 180°F to ensure effective sanitizing. Using a thermometer to check the water temperature is recommended.

How to use hot water as a sanitizer

Bring the fresh cantaloupe to the sink. Use a brush to scrub the outer surface of the cantaloupe under running water for 1 minute. This step is recommended by the FDA to achieve greater reduction of bacteria. Surface cleaning is followed by sanitizing, which involves soaking the whole cantaloupe in the hot water bath at 180°F for 5 minutes. After this sanitation period, the consumer can proceed to cut the cantaloupe using a clean knife.

How effective is hot water at destroying biofilms?

A biofilm is an aggregate of bacteria that occurs when the bacteria produce a slimy substance that coats the bacterial community, allowing the bacteria to attach to a surface. Biofilms act as an impenetrable fortress, protecting the bacterial community from the killing effect of sanitizers. This makes biofilms difficult to destroy, especially when using chemical sanitizers. However, another method worth considering is the use of hot water, given its effectiveness in destroying individual bacterial cells as well as those contained in biofilms. Our research group demonstrated that hot water could reduce the number of Salmonella Typhimurium and Listeria monocytogenes, under laboratory conditions. Some differences in bacterial reduction were observed between these two bacteria when hot water was used as a sanitizer. These differences were likely due to Listeria biofilms being biologically more resistant to heat compared to Salmonella.

Does hot water affect the quality of your cantaloupe?

No, it does not. After soaking the whole cantaloupe in hot water for 5 minutes, the fruit smells like blanched vegetables. But this odor disappears after the moisture on the surface dries out. 

Alternative sanitizers 

A few chemical options deserve consideration for use as sanitizers at home. It is important to remember to completely rinse the produce with water after the chemical sanitizer treatment in order to remove all chemical residues from the rind.

Takeaway key points

Good home sanitizing practices reduce the risk of getting sick from eating contaminated fresh produce, such as cantaloupes. The use of a readily available sanitizer at home, such as a hot water treatment, has shown to be an effective practice to ensure your family safe and high-quality fresh fruits and vegetables for consumption. The exposure time to the hot water may need to be reduced if you are using the hot water method to sanitize other fruits and vegetables that don’t have a thick rind like cantaloupes. This method would not be recommended for leafy greens, berries, herbs, or other fruits and vegetables that easily bruise or do not have a peel or a rind. An excellent way of helping to promote food safety is to disseminate these guidelines and recommendations to your peers, family, and friends.

Marler Clark has been in the middle and in the lead for all the Cantaloupe Outbreaks over the last decades. Here is a sampling:

Cantaloupe

Canada is reporting 26 ill in British Columbia 7, Ontario 7, Quebec 8, Prince Edward Island 2, Newfoundland and Labrador 2.

In the United States since the last update on November 17, 2023, 56 more illnesses have been reported. As of November 24, 99 people infected with the outbreak strain of Salmonella have been reported from 32 states. Arkansas 1, Arizona 7, California 1, Colorado 2, Georgia 3, Iowa 5, Illinois 4, Indiana 2, Kentucky 5, Massachusetts 1, Maryland 1, Michigan 1, Minnesota 13, Missouri 9, Mississippi 1, North Carolina 2, Nebraska 4, New Jersey 1, Nevada 2, New York 1, Ohio 8 Oklahoma 1, Oregon 1, Pennsylvania 1, Rhode Island 1, South Carolina 3, Tennessee 4, Texas 3, Utah 1, Virginia 1, Washington 1 and Wisconsin 8.

Illnesses started on dates ranging from October 17, 2023, to November 10, 2023.

Of 77 people with information available, 45 have been hospitalized. Two deaths have been reported from Minnesota.

Public health officials collect many different types of information from sick people, including their age, race, ethnicity, other demographics, and the foods they ate in the week before they got sick. This information provides clues to help investigators identify the source of the outbreak.  Age of ill ranges from less than 1 to 100 years of age.  60% are male and 40% are female.

State and local public health officials are interviewing people about the foods they ate in the week before they got sick. Of the 33 people interviewed, 29 (88%) reported eating cantaloupe. 

Recalled whole cantaloupe from the following brands:

  • Whole fresh cantaloupes with a label on the cantaloupe that says “Malichita” or “Rudy”, “4050”, and “Product of Mexico/produit du Mexique”
  • Cantaloupe was sold at retail stores in AZ, CA, MD, NJ, TN, IL, IN, KY, MI, OH, OK, WI, TX, FL, and Canada. This list may not include all states as the cantaloupes could have reached consumers through further retail distribution.
  • Retailers and wholesalers would have received recalled whole melons from Crown Jewels Produce in boxes labeled “Malachita/Z Farms” or from Sofia Produce doing business as TruFresh in boxes labeled “Malichita” or “Rudy.”

Recalled cut cantaloupe and products made from recalled whole cantaloupes:

  • ALDI cantaloupe, cut cantaloupe, and pineapple spears in clamshell packaging with Best-by dates between October 27 and October 31.
  • Vinyard cantaloupe chunks and cubes, fruit mixes, melon medleys, and fruit cups containing cantaloupe. Most have a “Vinyard” label, and some have a red label with “Fresh” sold between October 30 and November 10 in Oklahoma stores.
  • Freshness Guaranteed seasonal blend, melon trio, melon mix, fruit blend, fruit bowl, seasonal fruit tray, fruit mix, and cantaloupe chunks; and RaceTrac fruit medley sold in clear square or round plastic containers at select retail stores in IN, MI, OH, KY, NC, TN, VA, IL, TX, LA (see recall announcement for lot codes and “best by” dates).

CDC is advising people not to eat, sell, or serve recalled fruit.

fig-2

As of November 17, there have been 14 laboratory-confirmed cases of Salmonella Soahanina and Sundsvall illness linked to this outbreak in the following provinces: British Columbia (3), Ontario (3) and Quebec (8). Additional Salmonella infections are under investigation and more illnesses associated with this outbreak may be confirmed. Individuals became sick between mid-October and early-November 2023. Three individuals have been hospitalized. No deaths have been reported. Individuals who became ill are between 0 to 100 years of age. The majority of cases (57%) are female.

The Canadian Food Inspection Agency (CFIA) issued food recall warnings on November 1 and November 14 for Malichita brand cantaloupes sold between October 11 and November 14, 2023. Through the CFIA investigation the outbreak strain of Salmonella that made people sick was found in a sample of the recalled Malichita brand cantaloupe.

More recent illnesses may be reported in the outbreak because there is a period between when a person becomes ill and when the illness is reported to public health officials. For this outbreak, the illness reporting period is between 2 and 4 weeks.

The U.S. CDC is also investigating an outbreak of Salmonella Sundsvall illnesses linked to cantaloupes that is the same genetic strain as illnesses reported in this outbreak.

salmonella_bacteria
Image (c) Dennis Kunkel Microscopy, Inc.

It has long been said that, in 1885, pioneering American veterinary scientist, Daniel E. Salmon, discovered the first strain of Salmonella. Actually, though, Theobald Smith, research-assistant to Dr. Salmon, discovered the first strain of Salmonella—Salmonella Choleraesuis. But being in charge, Dr. Salmon received all of the credit.[1] Today, the number of known serotypes of Salmonella bacteria totals over two thousand. And in recent years, concerns have been raised, as particular strains of Salmonella have become resistant to traditional antibiotics.

There are two Salmonella species: Salmonella enterica (S. enterica) and Salmonella bongori (S. bongori). S. bongori strains predominantly colonize cold-blooded reptiles, whereas S. enterica strains are capable of infecting both humans and mammals.[2] Based on factors such as morphology, structure, mode of reproduction, and other criteria, the two species are further classified into subgroups called serotypes or serovars. More than 2,600 serotypes have been described for Salmonella, and they are characterized by the type(s) of animal they are found in or by the clinical symptoms they cause.[3] Of these, less than 100 are responsible for most human Salmonella infections.[4]

Where Does Salmonella Come From?

Salmonellae are widely distributed in nature and are found in the intestinal tract of wild and domesticated animals and in humans. Salmonella poisoning can occur when a person ingests contaminated fecal particles transmitted by another infected human or animal.[5]

Salmonella enterica serotypes Typhi, Sendai, and Paratyphi A, B, or C are found exclusively in humans. These serotypes, collectively referred to as typhoidal Salmonella, cause enteric fever (also known as typhoid or paratyphoid fever if caused by serotypes Typhi or Paratyphi, respectively).[6] Most often, enteric fever is acquired through ingestion of food or water contaminated with human feces. Most U.S. residents who are diagnosed with typhoidal Salmonella are infected while traveling abroad in areas where typhoid fever and paratyphoid fever are common. Three types of vaccines against S. Typhi are commercially available, although there is still not a single licensed vaccine available against S. Paratyphi A.[7] Persons planning to travel outside of the United States are advised to find out if a vaccine for typhoid fever is recommended (see www.cdc.gov/travel). 

Most Salmonella infections are caused by eating contaminated food. One study found that 87% of all confirmed cases of Salmonella are foodborne. Foods of animal origin, including meat, poultry, eggs, or dairy products can become contaminated with Salmonella. Eating uncooked or inadequately cooked food—or food cross contaminated with uncooked or undercooked products—can lead to human infections. As explained in a comprehensive report issued by the U.S. Department of Agriculture’s Economic Research Service:

Salmonella contamination occurs in a wide range of animal and plant products. Poultry products and eggs are frequently contaminated with S. Enteritidis, while beef products are commonly contaminated with S.Typhimurium. Other food sources of Salmonella may include raw milk or other dairy products and pork.

In the past two decades, consumption of produce, especially sprouts, tomatoes, fruits, leafy greens, nuts, and nut butters, has been associated with Salmonella illnesses.[8] The surface of fruits and vegetables may be contaminated by human or animal feces. Changes in food consumption and production, as well as the rapid growth of international trade in agricultural products, have facilitated the transmission of Salmonella associated with fresh fruits and vegetables. 

In the United States, Salmonella is the second most commonly isolated bacterial pathogen when laboratory diagnosis of diarrhea is sought.[9] However, passive laboratory surveillance, which uses voluntary reporting by health care providers and facilities, captures only a fraction of illnesses that actually occur. Furthermore, only a small proportion of illnesses are confirmed by laboratory testing and reported to public health agencies. Thus, researchers rely on quantitative statistical modeling to estimate the incidence of foodborne illness. These estimates are used to direct policy and interventions.

What are the Symptoms of Salmonellosis?

Salmonella infections can produce a broad range of disease, from no symptoms to severe illness. The most common clinical presentation is acute gastroenteritis. Symptoms commonly include diarrhea and abdominal cramps, often accompanied by fever of 100°F to 102°F (38°C to 39°C). More serious infections may also involve bloody diarrhea, vomiting, headache, and body aches.[10]

The Incubation period, or the time from Ingestion of the bacteria until the symptoms start, is generally 6 to 72 hours; however, there is evidence that in some situations the incubation can be longer than 10 days. People with salmonellosis usually recover without treatment within three to seven days. Nonetheless, Salmonella bacteria can persist in the intestinal tract and stool for many weeks after the resolution of symptoms—on average, one month in adults and longer in children.[11]

Treatment of Salmonellosis

S. Typhi and S. Paratyphi are capable of causing systemic illness if they invade the bloodstream (termed “bacteremia”). “Septicemia” or “sepsis” (bloodstream infection or “blood poisoning”) occurs if the bacteria multiply in the blood and cause the immune system to respond by activating inflammatory mechanisms. This may result in the development of “systemic inflammatory response syndrome,” or “SIRS.” By definition, SIRS includes tachycardia, tachypnea, fever, and abnormal white blood cell count. When the bacteria involved are S. Typhi or S. Paratyphi, this serious illness is called enteric typhoid, or paratyphoid fever. Symptoms may start gradually and include fever, headache, malaise, lethargy, and abdominal pain. In children, it can present seemingly innocuously as a non-specific fever. The incubation period for S. Typhi is usually 8 to 14 days, but it can range from three to 60 days. For S. Paratyphi infections, the incubation period is similar to that of nontyphoidal Salmonella—one to 10 days.[12]

Medical treatment is acutely important, though, if the patient becomes severely dehydrated or if the infection spreads from the intestines. Persons with severe diarrhea often require re-hydration, usually with intravenous (IV) fluids. But antibiotics are not necessary or indicated unless the infection spreads from the intestines, at which time the infection can be treated with ampicillin, gentamicin, trimethoprim/sulfamethoxazole, or ciprofloxacin. Unfortunately, though, some Salmonella bacteria have become resistant to antibiotics, largely as a result of the use of antibiotics to promote the growth of feed animals.[13]

[1]           Kass EH. (1987). A brief perspective on the early history of American infectious disease epidemiology. Yale J Biol Med. 60(4):341-8. 

[2]           Hernandez, A. K. C. Salmonella bongori. Poultry and Avian Diseases. Encyclopedia of Agriculture and Food Systems. https://www.sciencedirect.com/topics/agricultural-and-biological-sciences/salmonella-bongori.

[3]           Boore AL, et al. (2015). Salmonella enterica Infections in the United States and Assessment of Coefficients of Variation: A Novel Approach to Identify Epidemiologic Characteristics of Individual Serotypes, 1996–2011. PloS One. 10(12): e0145416

[4]           Besser JM. (2018). Salmonella epidemiology: a whirlwind of change. Food Microbiol. 71:55-9.

[5]           Chiu, C.-H. (2019). Salmonella, Non-Typhoidal Species (S. Choleraesuis, S. Enteritidis, S. Hadar, S. Typhimurium). http://www.antimicrobe.org/b258.asp. 

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