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Food poisoning

Last updated: December 1, 2020

Summary

Food poisoning, or foodborne illness, occurs following the ingestion of food or water contaminated with bacteria, bacterial toxins, viruses, parasites, or chemical substances. According to the Centers for Disease Control and Prevention (CDC), an estimated 1 in every 6 people in the US is annually affected with a foodborne illness. Risk factors include the cross-contamination of food, as well as improper handling and storage. In addition, immunocompromised individuals are at an increased risk of infection. Common pathogens attributed to food poisoning include Norovirus, Salmonella, Clostridium perfringens, Campylobacter jejuni, Staphylococcus aureus, and Escherichia coli. Incubation periods depend on the cause, and range from a few hours to days. The clinical presentation associated with food poisoning varies, but typical symptoms include diarrhea, nausea, vomiting, and abdominal cramping. Various laboratory tests (e.g., stool analysis, blood tests) help confirm the suspected diagnosis. Young children and the elderly are at greater risk for developing complications related to food poisoning and must be closely monitored. For most patients, supportive care, including fluid replenishment, is sufficient.

Staphylococcal food poisoning

References:[4]

Bacillus cereus infection

  • Pathogen: Bacillus cereus, a heat-stable, spore-forming bacterium that produces two different enterotoxins
  • Transmission: : The bacterium grows in heated food that cools down too slowly or is improperly refrigerated. Reheated rice is a common source of infection.[1]
  • Incubation period and clinical findings
  • Treatment: Supportive[4]

"Food poisoning from reheated rice? Be serious!" (B. cereus).
References:[5][6]

Seafood poisoning

Histamine fish poisoning (scombroid)

Reef fish poisoning (ciguatoxin)

  • Transmission: ingestion of reef fish containing Gambierdiscus toxicus
    • Barracuda
    • Sea Bass
    • Moray eel
    • Amberjack
    • Snapper
  • Mechanism of action: opening of Na+ channels; , resulting in depolarization
  • Clinical findings
  • Treatment: supportive

Puffer fish poisoning (tetrodotoxin)

Overview of foodborne diseases

Foodborne diseases may be classified according to the predominating symptoms. An overview is provided in this section. For details regarding the bacterial pathogens see the article “Bacterial gastroenteritis”.

Predominantly vomiting

Commonly due to delayed gastric emptying caused by changes to gastric motility.

Pathogen Foods/Transmission Incubation period Treatment

Staphylococcus aureus

(Enterotoxins cause the symptoms)

  • Canned meats, mayonnaise/potato salad, custards
  • 1–3 h
  • Supportive
Bacillus cereus
  • Reheated rice, food kept warm but not hot
  • Vomiting: 30 min to 6 h
  • Diarrhea: 6–15 h
  • Supportive

Noroviruses (e.g., Norwalk)

(Vomiting more common in children)

  • Fecal-oral
  • 12–48 h
  • Supportive

Predominantly diarrhea

Watery diarrhea

Typical pathomechanism of watery diarrhea: pathogen or toxin enters gastrointestinal tract → binds epithelial cells, sometimes damaging microvilli → ↑ secretion or ↓ absorption of hydrophilic molecules or electrolytes (e.g., NaCl) → ↑ intestinal water due to osmosisdiarrhea.

Enterotoxin or bacterial invasion shifts water and electrolyte excretion/absorption in proximal small intestinewatery diarrhea

  • WBC negative
  • No blood
Pathogen Foods/Transmission Incubation period Treatment
Staphylococcus aureus
  • Inadequately refrigerated food
  • Reheated meat dishes
  • Undercooked meat and raw legumes
  • 6–24 h
  • Recent travel (e.g., Asia, Africa, the Middle East, Mexico, Central, and South America)
  • Undercooked meat, endogenous
  • Fecal-oral
  • 9 h to 3 days
Listeria monocytogenes
  • Cheese, deli meats, coleslaw, hot dogs, unpasteurized milk
  • 1–2 days
Vibrio cholerae

Enteric viruses (adenovirus, norovirus, rotavirus)

  • Fecal-oral
Cryptosporidium
  • Fecal-oral
  • 5–7 days
Cyclospora (Cryptosporidium cyclospora cayetanensis)
  • Fecal-oral
  • 5–7 days
Intestinal tapeworms
  • Larvae in undercooked pork/beef, raw freshwater fish
  • 6–8 weeks
  • Asymptomatic for years

Invasive diarrhea

Pathogens penetrate the mucosa and invade the reticuloendothelial system of the distal small intestineenteric fever

  • WBC positive (fecal mononoculear leukocytes)
  • Blood may be present
Pathogen Foods/Transmission Incubation period Treatment
Yersinia
Salmonella typhi or paratyphi
  • Poultry/eggs

Inflammatory diarrhea

Typical pathomechanism of inflammatory diarrhea: pathogen enters gastrointestinal tractinflammationmucosal damage → barrier defect → diarrhea.

Bacteria or cytotoxins damage the colonic mucosablood in stool and fever

Pathogen Association Foods/Transmission Incubation period Treatment
Salmonella (100s of strains, including S. enteritidis and S. typhimurium)
  • Poultry/eggs
  • Chicken products: eggs, raw chicken
  • 6–48 h
Campylobacter jejuni
  • Most common bacterial organism pathogen responsible for foodborne gastroenteritis in the US
  • Poultry
  • Fecal-oral
  • Days
Shigella dysenteriae
  • Second most common association with hemolytic-uremic syndrome (HUS)
Fecal-oral
  • Days
Yersinia enterocolitica
  • Contaminated milk, pork
  • Days
Vibrio (usually parahaemolyticus)
  • Shellfish
  • Undercooked seafood
  • 16–72 hours

Enterohemorrhagic Escherichia coli (EHEC)

  • O157:H7: most common pathogenic strain; associated with HUS
  • Undercooked meat; most common association with hemolytic-uremic syndrome (HUS)
  • Non-disinfected water; contaminated food, such as unpasteurized dairy products (milk, soft cheese) or apple cider
  • Fecal-oral
  • 3–4 days
(range: 24 h to 10 days)
  • Supportive
  • Antibiotics are contraindicated because they increase the risk of HUS
Clostridium difficile

Additional non-gastrointestinal symptoms

Pathogens Predominating symptoms Foods/Transmission Incubation period Treatment
Clostridium botulinum
  • Descending paralysis
  • Adults: respiratory support, antitoxin
  • Infants: respiratory support, hyperimmune human serum
  • Do not use antibiotics! .
Histamine fish poisoning
  • Inadequately refrigerated fish
  • 5 min to 1 h
Brucellosis (Brucella spp.)
  • Unpasteurized dairy products
  • Contact with animals (e.g., hunter)
  • 2-4 weeks (range: 5 days to 5 months)
Hepatitis A (Hepatitis A virus)
  • Jaundice, commonly following initial GI symptoms
  • Fecal-oral
  • 28 days (range 14–50 days)
  • Supportive (generally self-limiting)
  • Immune serum globulin
  • Vaccine

Vibrio vulnificus

  • Oysters, undercooked seafood
  • 1–7 days
Salmonella typhi and paratyphi
  • Fecal-oral
  • Hours

Common vectors for fecal-oral transmission in intestinal diseases are the 5 F's: fingers, feces, food, fluids, flies.
References:[1][2][4][6][7][8][9][10][11][12][13][14][15][16][17][18][18][19][20][21][22][23][24][25][26][27][28][29][30]

Food and water safety

  • Food hygiene
    • Wash hands and surfaces frequently
    • Wash fruits and vegetables with safe drinking water
    • Avoid cross-contamination by keeping raw meat products, eggs and seafood separated from other kinds of food
    • Use a food thermometer while cooking
    • Maintain a refrigerator temperature < 4°C (40°F)
    • When traveling (especially to developing countries): only consume fully cooked or dry (e.g., bread, crackers) foods, pasteurized dairy products, and fruits and vegetables you can peel or have properly washed yourself
  • Water hygiene
    • Do not consume untreated water or ice
    • Options if water treatment is unknown:
      • Consume sealed bottled beverages
      • Boil water for at least one minute before consuming
      • Use an appropriate filter

There is a simple rule to avoid foodborne illness while traveling: Boil it, cook it, peel it, or forget it!
References:[31][32]

References

  1. Bacillus cereus. http://www.fda.gov/food/foodborneillnesscontaminants/causesofillnessbadbugbook/ucm070492.htm. Updated: January 1, 2012. Accessed: October 6, 2016.
  2. Klochko A. Salmonellosis. Salmonellosis. New York, NY: WebMD. http://emedicine.medscape.com/article/228174-overview#showall. Updated: October 21, 2016. Accessed: March 25, 2017.
  3. Ho H. Vibrio Infections. Vibrio Infections. New York, NY: WebMD. http://emedicine.medscape.com/article/232038-overview. Updated: September 25, 2014. Accessed: March 25, 2017.
  4. Rosenthal KS, Tan MJ. Rapid Review Microbiology and Immunology, 3rd Edition. Elsevier ; 2010
  5. E.coli (Escherichia coli). https://www.cdc.gov/ecoli/general/. Updated: November 6, 2015. Accessed: April 10, 2017.
  6. Eley AR. Microbial Food Poisoning. Chapman & Hall ; 1996
  7. Fiore AE. Hepatitis A transmitted by food. Clin Infect Dis. 2004; 38 (5): p.705-715. doi: 10.1086/381671 . | Open in Read by QxMD
  8. Bross MH, Soch K, Morales R, Mitchell RB. Vibrio vulnificus Infection: Diagnosis and Treatment. Am Fam Physician. 2007; 76 (4): p.539-544.
  9. Daniels NA. Vibrio vulnificus oysters: pearls and perils. Clin Infect Dis. 2011; 52 (6): p.788-792. doi: 10.1093/cid/ciq251 . | Open in Read by QxMD
  10. Fish Poisoning in Travelers: Ciguatera and Scombroid. https://wwwnc.cdc.gov/travel/page/fish-poisoning-ciguatera-scombroid. Updated: January 30, 2014. Accessed: April 10, 2017.
  11. Brucellosis: Transmission. https://www.cdc.gov/brucellosis/transmission/index.html. Updated: November 12, 2012. Accessed: April 10, 2017.
  12. Norovirus (Norwalk Virus). https://www.foodsafety.gov/poisoning/causes/bacteriaviruses/norovirus/. Updated: April 10, 2017. Accessed: April 10, 2017.
  13. Clostridium perfringens. https://www.foodsafety.gov/poisoning/causes/bacteriaviruses/cperfringens/. Updated: April 10, 2017. Accessed: April 10, 2017.
  14. Brunette GW, Kozarsky PE, Cohen NJ, et al. The Yellow Book: CDC Health Information for International Travel 2016. Oxford University Press ; 2015
  15. Weinstein KB. Listeria Monocytogenes Infection (Listeriosis). Listeria Monocytogenes Infection (Listeriosis). New York, NY: WebMD. http://emedicine.medscape.com/article/220684. Updated: December 15, 2016. Accessed: April 10, 2017.
  16. Vibrio Infections. https://www.foodsafety.gov/poisoning/causes/bacteriaviruses/vibrio_infections/. Updated: April 10, 2017. Accessed: April 10, 2017.
  17. Taeniasis/cysticercosis. http://www.who.int/mediacentre/factsheets/fs376/en/. Updated: March 1, 2017. Accessed: April 10, 2017.
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  19. Llewelyn H, Ang HA, Lewis K, Al-Abdullah A. Oxford Handbook of Clinical Diagnosis. Oxford University Press ; 2014
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  21. Tyring SK. Mucosal Immunology and Virology. Springer ; 2006
  22. Vibrio Species Causing Vibriosis. https://www.cdc.gov/vibrio/index.html. Updated: October 24, 2016. Accessed: April 10, 2017.
  23. Irizarry L. Tapeworm Infestation. Tapeworm Infestation. New York, NY: WebMD. http://emedicine.medscape.com/article/786292. Updated: July 28, 2015. Accessed: April 10, 2017.
  24. Treatment for Cyclosporiasis. https://www.cdc.gov/parasites/cyclosporiasis/health_professionals/tx.html. Updated: January 10, 2013. Accessed: April 10, 2017.
  25. Cryptosporidium: Treatment. https://www.cdc.gov/parasites/crypto/treatment.html. Updated: February 20, 2015. Accessed: April 10, 2017.
  26. Food Safety: Clostridium perfringens. https://www.cdc.gov/foodsafety/diseases/clostridium-perfringens.html. Updated: January 10, 2017. Accessed: April 10, 2017.
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  28. Symptoms of Food Poisoning. https://www.foodsafety.gov/poisoning/symptoms/symptoms.html. Updated: April 10, 2017. Accessed: April 10, 2017.
  29. Staphylococcal Food Poisoning - CDC. https://www.cdc.gov/foodsafety/diseases/staphylococcal.html. Updated: August 9, 2018. Accessed: April 30, 2020.
  30. Food Safety: Information for the Public. https://www.cdc.gov/foodsafety/groups/consumers.html. Updated: September 1, 2016. Accessed: April 10, 2017.
  31. Cryptosporidium: Prevention & Control: General Public. https://www.cdc.gov/parasites/crypto/gen_info/prevention-general-public.html. Updated: October 7, 2015. Accessed: April 10, 2017.
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