LEC 10: Toxins in Food PT 2

What do allergen tests measure? List 5 allergen tests

• Measures the presence of antibodies to specific allergens (eg, IgE, or “Immunoglobulin E” is the antibody that triggers food allergy symptoms)

• skin prick test

• skin patch test

• blood test

• elimination diet

• oral immunotherapy

What are the immediate results + drawbacks of the skin prick test + skin patch test?

• Skin Prick Test: aka puncture or scratch test

  • Immediate results. Also tests sensitivity to pollen, pet dander, or mold (up to 40 different substances at the same time)

  • Drawback: Test is affected by antihistamines or people with extensive rashes

• Skin Patch Test

  • Immediate results. Identifies particular substances the cause contact dermatitis (ie, skin irritation or inflammation due to contract w/DMF)

  • Drawback: Test usually takes place over the court of 2 to 3 office visits

Explain the blood test + elimination diet and their drawbacks?

• Blood Test

  • Not affected by antihistamines

  • Can be used for people with sensitive skin or who have had a bad reaction to a skin test

  • Drawback: A more expensive test + results take a few days

• Elimination Diet

  • Patient cuts out certain foods for 2 to 4 weeks to see if any allergy symptoms occur during that time

  • If not, your doctor will ask you to start eating the foods again to see if symptoms return. If so, there’s a good chance you’re allergic to those foods

  • Drawback: trial + error testing

2 treatments for food allergies are allergy shots + sublingual immontherapy. What are their drawbacks?

• Allergy Shots

  • Immunotherapy through injection of allergen extracts

  • Beneficial for people with multiple allergies such as to molds, pollens, pet dander, + dust mites

  • FDA approved for many years

  • Drawbacks: Need to be given in a physician’s office due to the potential for severe side effects

• Sublingual Immunotherapy (SLIT), aka allergy drops

  • A form of immunotherapy that involves putting drops (or tablets) of allergen extracts under the tongue (can be self-administered)

  • An alternative treatment for allergy shots

  • Serious reactions are extremely rare

  • Generally, SLIT is administered once daily for a period of years

  • Drawback: Most allergy drops not FDA approved in the US. However (3/1/2027) FDA approved 3 different formulations for grass allergy, ragweed, + dust mites. Also not recommended for people with multiple allergies 

Define oral immunotherapy + how is it given? What is its drawback?

• Oral Immunotherapy

  • Often considered the “Gold Standard” for food allergy testing

  • Should only be done in a medical office by an allergist

  • Doctor gives very small amounts of food allergen + watches for symptoms

  • If no symptoms occur, larger doses are slowly given

  • If no symptoms appear, the test will be stopped

  • Drawback: Process is time consuming, usually takes 4-8 hours to complete, but can be a very reliable test 

What is Salmonella?

• Salmonella isn’t the actual name of the intestinal infection

  • It is a bacterium that causes Salmonellosis
    

• It is the second most common bacterial foodborne illness

• Most commonly reported cause of enteric (intestinal) disease

How can you be exposed to Salmonella? List 7 places where the organism can be found in contaminated/infected?

• The bacteria are passed from the feces of animals

  • So, if you eat anything + then get Salmonellosis, the food was contaminated with animal feces…
    

• The organism can be found in contaminated/infected

  • Water

  • Soil

  • Insects

  • Factory surfaces

  • Kitchen surfaces

  • Raw meats + poultry

  • Raw seafood

How do you know if your infected by salmonella?

• Symptoms

  • Ulcers

  • Chills

  • Abdominal pain

  • Leukocytosis (abnormal white blood cell count)

  • diarrhea

How can Salmonella poisoning be prevented? (9)

• Wash your hands, wash cutting boards. Be smart with your food

• Keep raw meat away from fruits, veggies, + food that is cooked or ready to eat

• Refrigerate food as soon as you get back from the supermarket

• Do not defrost food at room temperature

• Cook thoroughly

• Serve soon

• Cool below 40F (22C)

• Wash everything after contact with raw sources

• Never use the same cutting board for raw meats + vegetables 

What does E. Coli produce? Explain Shiga toxin-producing E. coli (STEC)

• Produce infections in humans + animals

• Named for Theodor Escherich, a German physician

• Grow between 10-40C (50-104F): optimal at 37C (98.6F)

• More than 700 different strains of E. coli

  • Shiga toxin-producing E. coli (STEC) causes the illness

    • First diagnosed as a pathogen (infectious disease-causing microorganism) to 1982

List 5 things causes E. Coli Transmission in Humans?

Undercooked or unpasteurized animal products

foods contaminated with feces

Contaminated water

Contaminated soil

Direct person-to-person contact

E. Coli Transmissions in Humans: found in what undercooked or unpasteurized animal products(3) + foods contaminated with feces (2), contaminated water (2)

• Undercooked or unpasteurized animal products

  • Ground beef

  • Other meats

  • Milk, cheese
    

• Foods contaminated with feces

  • Fruits

  • Vegetables

• Contaminated water

  • Private wells

  • Swimming in contaminated lakes + streams

E. Coli Transmissions in Humans: found in what contaminated soil (2) + direct person-to-person contact (3)

• Contaminated soil

  • Campgrounds

  • Sites grazed by livestock

• Direct person-to-person contact

  • Diaper changing

  • Improper sanitation

  • Day care + chronic adult care facilities 

How many days until most patients recover from E. Coli poisoning? List 6 symptoms

• Incubation Period (3-4 days after exposure)

  • Most patients recover within 7 days
    

• Symptoms include

  • Fever

  • Bloody/non-bloody diarrhea

  • Vomiting

  • Nausea

  • Kidney failure

  • Hemolytic anemia

What are 3 things to treat E. Coli Poisoning

• Fluid replacement

• Rest

• No antibiotics - unless symptoms become systemic (ie, affect entire body)

Summary card

• There are many toxins derived from natural + organic sources that have the ability to cause harm + even death to humans

  • These include mycotoxins + bacterial infections
    

• Special caution should be taken when handling + preparing foods for consumption in order to prevent inadvertent poisoning by such toxins

• Luckily for many types of food poisoning, there are antidotes + treatments available if caught early on

  • Preventive strategies are key to avoiding potential health risks!