Food Micro Final - Food Safety/ Foodborne Illness

foods associated with Non-hemorrhagic type E. coli

Non-hemorrhagic types : human fecal contaminant EPEC- contaminated water for bottle fed infants in developing countries ETEC- water or food contaminated with human feces

pathogen leading to most foodborne illnesses

Norovirus

pathogen leading to most foodborne deaths

Salmonella

Pathogens that wait and produce toxin in the body

Shigella, Salmonella, etc.

infant botulism

consuming spores big deal for age 2 or under, because they don't have established microflora, the GI tract is void of organisms often associated with honey (relieve coughs, colic) but may contain C. botulinum spores

way shigella gets into system:

contaminated water, sanitation irrigation water greater issue than municipal

what most happen before illness can occur?

contamination event (H2O, rodents, mishandling, improper storage)

3 most common parasites

cryptosporidium, cyclospora, giardia

foods associated with salmonella

eggs, poultry, meat, cheese, raw fruits/ veggies common occurrence with animals (poultry, pork)

illnesses associated with salmonella

enteric fever - typhoid strains salmonellosis - enterocolitis (inflammation of intestinal tract) due to other salmonella

causes of salmonella

fecal contaminant, inadequate cooking, cross contamination, using contaminated raw ingredients

foodborne disease - main issue

food service and mass feeding settings; improper food storage and preparation practices

foods associated with bacillus cereus

foods held at too warm of temps foods not heated sufficiently to eliminate spores, if present vomiting type - associated with rice products and other starchy foods (potatoes, pasta, cheese) diarrhea type - wide variety foods (meat, veggies, milk, fish, sauces, soups, salads)

prevention/ reduction of C. botulinum

proper thermal processing and refrigeration using preservatives - nitrite/ nitrate, sorbate -Class 1 recall since its life threatening

foods associated with campylobacter

raw and undercooked poultry, contaminated water, unpasteurized milk

foods containing shigella

raw produce, contaminated drinking water, uncooked foods and cooked foods that are not reheated after contact with infected handler

way bacillus cereus gets into food

very common in environment

treating staph aureus

wait it out, take a lot of fluids

prevention/treatment of E. coli

water quality and sanitation issues addressed typical thermal treatment to kill salmonella will kill E. coli

issue leading to bacillus cereus

underprocessing and mishandling foods

Staphylococcus aureus facts

-often occurs due to mishandling -enterotoxin -gram positive coccus -can grow at elevated salt levels (up to 15%) -infects GI tract -sudden onset, 1-6 hours -duration: 1-2 days -symptoms: nausea, vomiting, cramping, diarrhea

host defense mechanisms

-pathogens can't survive from pH 2.5-3.5 -Bile acid resistant to gram + bacteria, -Peristalsis (muscle contractions, hard for microbes to attach to intestinal cell) -purging, diarrhea or vomiting -immunological factors (antigen and antibody reaction may occur) -gastric acid -hepatic filtration (filtered out in liver) -mucus -epithelium/ epithelial cells are barrier -indigenous microflora (acts on food mass to degrade it, inhibitory to invading microbes)

factors leading to foodborne illness outbreaks

1. improper processing 2. poor personal hygiene 3. cross contamination 4. improper reheating 5. poor storage practices

5 categories of foodborne illness

1. infections 2. intoxications 3. metabolic food disorders 4. allergies 5. idiosyncratic illnesses

to determine hazards of foodborne disease, need to know:

1. pathogens that are potential problems with a particular product 2. factors that control the growth and survival of pathogens 3. factors that can be used to eliminate pathogens

ways to destroy or remove foodborne pathogens

1. proper thermal processing 2. freezing (slows growth) 3. high pressure 4. irradiation 5. antimicrobials

ways to prevent cross contamination

1. separate raw and ready to eat foods 2. hazard analysis - severity and likelihood event occurs 3. chlorinate wash water to reduce contamination in RTE foods

factors influencing infectious dose

1. susceptibility of host (age, health history, what they have eaten) 2. infectious nature of pathogen 3. ability to produce toxins 4. processing and handling practices

symptoms / frequency/ treatment of C. botulinum

10-30 foodborne outbreaks/ yr onset: 12-72 hrs duration varies symptoms: weakness, double vision, hard to speak and swallow, constipation, hard to breathe treatment: antitoxin, respiration/ nutrition care

ideal food warming temps

135 F or above if temp drops to 125 F, in growth range of pathogens thermophilic spoilage may occur

temperature leading to pathogen rapid growth range/ very dangerous

25 - 40 C (77 - 104 F)

shigella facts

4 types, all produce toxins nonmotile gram negative rod facultative anaerobe illness: bacterial dysentery or shigellosis

danger zone of pathogens

5 - 55 C (41 - 131 F)

infectious dose of c. perfringens

> 10^8 vegetative cells if consuming more than 1 million/ gram, issues arise

most toxic types of C. botulinum

A and B

Pathogens where the toxin already present/ produced on food

C. botulinum B. cereus S. aureus

Enterohemorrhagic E. coli (EHEC) - hemorrhagic colitis

E. coli 0157: H7, hemorrhagic colitis - onset: 1-8 days, duration: 5-10 days, severe cramps, watery then bloody diarrhea. common in children less than age 4.

pathogens that are hazards at any level

E. coli 0157:H7 Shigella Cyclospora

Feces from ruminant animals (cattle/sheep) coming in contact with food is associated with what pathogen

EHEC

E. coli 0157:H7

EHEC combo of antigens 0157: somatic antigen H7: flagellant antigen causes GI tract issues

EPEC and EIEC illnesses

EPEC- infantile diarrhea EIEC- bacillary dysentery occurs sporadically due to sanitation issues

which intestine does ETEC and EHEC affect?

ETEC- small intestine EHEC- large intestine

EIP

Emerging Infections Program of CDC

Enterohemorrhagic E. coli (EHEC) - hemolytic uremic syndrome (HES)

HUS - in young kids, leaves the GI tract, infects the circulatory system, infects the kidneys - causes major kidney damage

pathogen that grows at refrigeration temps

Listeria

bacillus cereus symptoms

Most cases go unreported - no complications usually. produces 2 different kinds of toxins- its one OR other. Both last about 24 hours. 1. vomiting (emetic), duration 6-15 hr 2. diarrhea, duration 0.5-6 hr

EHEC Thrombotic thrombocytopenic purpura (TTP)

TTP is rare. the organism relocates to the brain and impairs brain, usually results in death

two pathogens with high mortality rate, but low number of illnesses/ occurrences (basically when it happens, its bad)

Toxoplasma gondii and Listeria monocytogenes

foodborne pathogens biggest risk to people at what age

Under age 5

FoodNET

active surveillance measure, principle foodborne disease component of CDC's emerging infections program (EIP)

factors that can control pathogen survival and growth

aerobic conditions Aw pH temperature nutrients proper O2 level

pathway of salmonella enterotoxin

after ingesting, passes through GI tract to epithelial cells. attaches to receptor site and produces enterotoxin. affects fluid flow of the cell. causes water to diffuse out of body into intestinal tract - causing diarrhea

food safety - purpose

aim to determine what hazards can be related with a specific product and process, and try to control the situation. basically - reduce the risk and hazard level to make a safe product

prevention/ reduction of C. perfringens

almost impossible to completely avoid contamination - limit the problem with proper food handling cook food then quickly cool so spores don't germinate

serovar

antigenic makeup on cell surface or flagella - degree of virulence influences it. antigens/ antibody rxn helps identify salmonella between each serovar

infectious dose of shigella

as little as 10 cells can cause illness

how does campylobacter get in food

bird picks up microbe, infects GI tract of chickens, spreads from bird to bird (not harming animal) -if its a positive flock, spread contaminant in processing facility

C. botulinum type E

found naturally in aquatic environments associated with fish and shellfish sensitive to heat can grow at cold temps (3.3 C) and in fridge

Enterotoxigenic E. coli (ETEC)

gastroenteritis, travelers diarrhea (going to another country and eating/ drinking) onset: 1-3 days duration: 3-7 days symptoms: watery diarrhea, ab cramps, low-grade fever, nausea, and malaise more inconvenient issue - not super serious

E. coli facts

gram negative facultative anaerobe 4 types: EPEC and EIEC - waterborne, sanitation issue in developing world; ETEC and EHEC - foodborne

Campylobacter jejuni facts

gram negative curved rod motile microaerophile (reduced O2 levels, and increased CO2 levels) sensitive to stresses of environment- goes dormant then can be reactivated. heat sensitive-killed easily. hard to isolate/ identify

salmonella facts

gram negative rod facultative anaerobe 5-45 C pH 4-9, high Aw, heat resistant for a non sporeformer can remain viable outside host (chickens) - inoculated in soil, hangs out til conditions improve

Clostridium botulinum facts

gram positive rod anaerobic forms endospores Types A, B, and E affect foods

Listeria facts

gram positive rod humans are intestinal carriers relatively hardy non-sporeformer found in environment (plants, soil, crevices in food processing) grows at fridge temps

Enterohemorrhagic E. coli (EHEC) occurrence

half due to 0157: H7 not as numerable as salmonella, but serious symptoms

food associated with c. perfringens

high protein foods (meat and poultry) gravy dried or precooked foods time/ temp abused foods

what is c. botulinum outbreaks due most often to

improperly preparing food, home canning/ fermentation not often in commercial uses naturally found in soil (A and B)

prevention of shigella

improved water quality and sanitation, processes that eliminate other pathogens (salmonella) are effective

foods associated with hemorrhagic type E. coli

intestinal tract of cattle is primary reservoir for 0157:H7. Feces from ruminant animals (cattle/sheep) coming in contact with food. undercooked beef (hamburger), unpasteurized milk and juice, raw fruits and veggies (sprouts), and contaminated water

limitations of FoodNET

limited to diagnosed diseases, some illnesses acquired through non-foodborne routes (contaminated water, person-person, direct animal contact)

dysentery

lots of watery diarrhea (blood and pus with the stool)

salmonella infectious dose

low (15-20) or high frequency very high in US (2-4 million)/yr

campylobacter infectious dose

low 400-500 treat with fluids

typical foods associated with C. botulinum

low acid foods (pH 4.6) improperly canned foods, fermented fish, baked potatoes in aluminum foil

Enterotoxigenic E. coli (ETEC) occurrence

more common with travelers to foreign countries - eating/ drinking

2 most common virus types

norovirus (Norwalk virus) and hepatitis A

infectious dose

number of pathogens needed to bring about illness in an individual

Campylobacteriosis symptoms

onset: 2-5 days duration: 2-10 days symptoms: diarrhea (may be bloody), cramps, fever, vomiting low mortality rate - usually no complications very common pathogen

symptoms of shigella

onset: 4-7 days duration: 1-2 days symptoms: ab cramps, diarrhea, fever, vomiting; blood, mucus, pus in stools with watery diarrhea

symptoms/ treatment of salmonella

onset: 6-48 hrs duration: 4-7 days acute symptoms: fever, vomiting, nausea, diarrhea, cramps chronic: arthritis after about 1 month treat with lots of fluids

symptoms of clostridium perfringens

onset: 8-16 hours duration: 1 day symptoms: intense abdominal cramps and watery diarrhea very common in USA

Listeria symptoms

onset: 9-48 hours for GI symptoms; 2-6 weeks for invasive illness influenza and GI like symptoms invasive manifestation: meningitis, encephalitis, cervical infection BIG danger to pregnant women - stillborn, lose child

what pH are C. botulinum spores inactivated

pH 4.6

foodborne infection

pathogen must survive passage to intestines, then takes root in the gut ex) Salmonella, Listeria, E. coli, Shigella

nature of C. botulinum toxin

preformed toxin most lethal natural substance heat labile protein (inactivated at 80 C) - easily denatured at high temps toxin forms in the food by the organism

foods associated with staph aureus

previously heated foods more foodservice than processed foods unrefrigerated or improperly refrigerated meats, potato and egg salads

2 main species of salmonella

s. enterica and s. bongori

how does staph aureus usually occur

sanitation breakdown

prevention of campylobacter

sanitation, proper food service / hygiene issue, flock management, heat processing effective (killed fast)

preventing bacillus cereus

sanitation, proper time/ temperature thermal treatments, proper holding temps can prevent spore growth

prevention/ reduction strategy of staph aureus

sanitation; proper heating, cooling and reheating, holding temps

most severe shigella strain

shigella dysenteriae. issue in developing countries with poor water and sanitation

most common shigella strain in USA

shigella sonnei (mild type)

formula for infectious dose

strain of organism / infectious nature

prevention of salmonella

temp, pH, Aw, sanitation, time/ temp proper time/ temp combo usually eliminates

path of C. botulinum

toxin absorbed from GI tract, enters circulatory system, then affects the nerves blocks acetylcholine release - causing nerve paralysis/ blocking of signal

bacillus cereus facts

toxin preformed on food spore forming gram positive rod facultative anaerobe very common in environment temp: 10-50 C pH: 4.9-9.3

Enterotoxins

toxin that is produced in or affecting intestines, enters through contaminated food or water

foodborne intoxication

toxins are formed on the food, must survive passage through GI and remain active ex) Campylobacter, Staphylcoccus aureus, Bacillus cereus, Clostridium botulinum

Clostridium perfringens facts

types A and C related to foodborne issues gram positive rod enterotoxin, but NOT preformed toxin anaerobic forms endospores - may not form readily in foods short generation time (could be 10 min) may produce large amounts of gas (soup/ gravy have frothy tops)