EXAM 3 CHART MATERIAL

Isoniazid

* Growth Factor Analogs
* Synthetic (chemical)
* Cidal (if actively growing)
* Static (if dormant)
* Disrupts cell metabolism
* Narrow spectrum
* Structurally similar to an essential growth factor
* Used against acid-fast bacteria

Ciprofloxacin

* Quinolones
* Synthetic (Chemical)
* Cidal
* Interferes with bacterial DNA gyrase
* Narrow spectrum
* Prevents DNA packaging
* Used to treat UTIs
* Goes against gram neg

Erythromycin

* Macrolides
* Antibiotic
* Static
* Targets 50S ribosomal subunit
* Broad spectrum
* Gram pos and gram neg

Azithromycin (Z-pack)

* Macrolides
* Semi-synthetic (of erythromycin)
* Static
* Targets 50S ribosomal subunit
* Broader spectrum
* Gram pos and gram neg

Tetracycline

* Tetracyclines
* Antibiotic
* Static
* Targets the 30S ribosomal subunit
* Broad spectrum
* Used to treat acne

Platensimycin

* Lipid Biosynthesis Disruptor
* Antibiotic
* Static
* Targets fatty acid biosynthesis
* Broad spectrum
* Effective against MRSA and VRE (resistant strains that are hard to treat)

Penicillin

* B-lactam
* Antibiotic 
* Cidal against actively growing bacteria
* Targets cell wall synthesis (disrupts transpeptidation)
* Narrow spectrum
* Effective against gram pos
* Many semi-synthetics made from this that aren’t as impacted by B-lactamases and have a broader spectrum

Staphylococcal Food Intoxication (S. aureus)

* Intoxication, toxins ingested
* Onset: Rapid, 1-8 hours
* Symptoms
* **Explosive Vomiting**
* **No fever** (subnormal body temp)
* general ones: nausea, diarrhea, headache, weakness, etc
* Duration: 1-2 days
* Susceptible: Anyone
* Gram pos, Cocci, Facultative aerobe, can survive in low water activity
* Source: human nasal cavity, skin, skin sores
* Enterotoxin producer → heat stable and resistant to acid changes (Super Antigen)
* Food kept in danger zone for long time
* think: foods with salt, or others that can lower water activity

Botulism (C. botulinum)

* Intoxication, toxins ingested
* Onset: 18-24 hours
* Symptoms
* **Difficulty breathing, swallowing, and speaking**
* **No fever**
* **Blurred vision**
* **Heart paralysis**
* **Constipation**
* **Nausea**
* **Cramps**
* **Sometimes vomiting**
* Duration: 1-10 days
* Susceptible: Anyone
* Gram pos, bacilli, spore-forming, strict anaerobe
* Source: soil and water
* Neurotoxin → exotoxin, heat labile, best produced in basic foods with lots of protein, destroyed by high heat
* Mortality: 3-5%
* Treatment: Antitoxin
* think: canned foods, foods that are basic, etc

*C. perferigens* food infection

* Infection, microbes ingested
* Onset: 7-15 hours
* Symptoms:
* **Diarrhea**
* **Cramps**
* **Nausea**
* **Fever and vomiting = rare**
* Duration: 12-24 hours
* Susceptible: Anyone
* Gram pos
* Spores activated by cooking and germinate under anoxic conditions
* Outbreaks in food in bulk → no stirring = anoxic conditions
* think: any food in bulk or that has anoxic conditions (bulk more likely than anything)

Salmonellosis (S. enterica)

* Infection
* Onset: 8-48 hours
* Symptoms
* **Enterocolitis (vomiting, diarrhea, fever)**
* Chills
* Headache
* Duration: 2-5 days
* Susceptible: Anyone
* Gram neg, bacilli, facultative aerobe
* Infectious dose: 10^7-10^9 viable cells
* Virulence factors: endotoxins (Lipid A of LPS), enterotoxins, cytotoxins
* 10-20% of victims are carriers for 4-8 weeks
* think: honestly i think of meats, dairy, eggs, etc with this

*E. coli* food infection (E. coli O157:H7)

* Infection
* Onset: 3-5 days
* Symptoms
* **Bloody diarrhea**
* **Kidney Failure**
* intense abdominal pain
* fever and vomiting are rare
* **brain damage**
* **death**
* Duration: 5-10 days
* Susceptible: Anyone
* Gram neg, fac. Aerobe, coccobacilli
* Source: sewage
* Strains: (6) ETEC (travelers diarrhea), EPEC (infantile diarrhea), EIEC (watery diarrhea), STEC (shiga toxin/ enterohemorrhagic) (bloody diarrhea)
* Contaminated water, etc
* 50% mortality rate once kidney failure begins
* Infectious dose: SMALL
* **Verotoxin**: hemorrhagic colitis, hemolytic uremic syndrome
* Leading cause of kidney failure in children
* think: undercooked meat, contaminated water, veggies and stuff

*Campylobacter* food infection

* Infection
* Onset: 2-10 days
* Symptoms
* **High fever**
* **Malaise**
* Headaches
* Severe diarrhea
* vomiting uncommon
* **Occasionally, ulceration of the ileum (bloody stools but not black like** ***E. coli***\*\*)\*\*
* Duration: 1-10 days
* Susceptible:
* Immunocompromised
* Young
* Old
* Gram neg, motile, microaerophile
* Source: GI of animals
* Destroyed by pasteurization, sensitive to air, freezing, and gastric acid
* Heat-tolerant, grows best in body temps and higher (37C-42C)
* *C. jejuni* and *C. fetus* often
* Infectious dose: 500-10^4
* Enterotoxin and cytotoxin
* think: honestly could be any food but it needs to have something where it gets some oxygen but not too much

Listeriosis (L. monocytogenes)

* Infection
* Onset: Few days to 2 months
* Symptoms
* **Miscarriages**
* **Loss of balance**
* **Meningitis**
* **Bacteremia**
* Confusion
* Fever
* Muscle aches
* Nausea
* Diarrhea
* Headache
* Duration: 5-10 days
* Susceptible:
* Immunocompromised
* Young
* Old
* Pregnant women
* Gram pos, facultative aerobe, coccobacilli, psychrotolerant, acid-tolerant, salt-tolerant
* Sources: soil, water, fecal material, vegetation, silage
* Grows into the leaves of veggies
* Invasive → proliferation in phagocytes
* Infectious dose = < 1000 in susceptible people
* Cause an estimated 20% of all deaths from foodborne illnesses
* think: acidic foods, salty foods, veggies (grows into the leaves), etc (on the rinds of canteloupe, etc)

Boiling

Moist Heat

Disinfect

Destroys bacteria, fungi, and viruses (not endospores)

Pasteurization

Moist Heat

Disinfect

Controlled heating at temps below boiling

Kills pathogens

Reduces total microbial load

Autoclaving

Moist Heat

Sterilize

Will kill endospores if done correctly

Pressure = 15 psi

Temperature = 121 degrees C

Time = 15-20 minutes

^ can change depending on what is being done

Dry Heat Sterilizer

Dry Heat

Disinfect (?)

Dry heat, in general, is less effective than moist heat

Used for things that cannot interact with water

Requires higher temps and longer exposure times  

Flamming

Dry Heat

Sterilize (?)

Doesn’t last very long

Freezing

Cold Temperature

Neither (partially disinfects, kind of)

Stops microbial reproduction

Some organisms are killed by ice crystal formation/disruption in the cell membrane

Refrigerating

Cold Temperature

Neither

Slows microbial reproduction and growth

UV Radiation 

UV Radiation

Disinfect 

Non-ionizing radiation

Most bacteriocidal wavelength is 260 nm

Creates thymine dimers in DNA

Poor penetrating power → limited to the disinfection of surfaces, air, and water (limited by glass, plastic, dirt films, etc)

Ionizing Radiation

Ionizing Radiation (cold temp)

Sterilize

Beta, gamma, and X-Rays

Penetrates deep into objects

Cold sterilization

Good for things that cannot be exposed to heat or water

Filtration

Filtration

Sterilizes only if specific membrane sizes used

Reduces microbial populations

Sterilization of heat-sensitive solutions (must use membrane filter with defined pore size)

Use for air as well

Viruses

* most foodborne illnesses caused by these


* symptoms:
* gastroenteritis (diarrhea, nausea, vomiting)
* incubation: 12-24 hours
* spontaneous recovery (usually within 24-48 hours)
* noro- most common
* other less common ones:
* rota-, astro-, and Hep A

Giardia and Cryptosporidium

protozoa

spread via food contaminated by fecal matter in untreated water that was used to irrigate or spray crops and via drinking water

foods involved: fresh foods (fruits) often imported from other countries

C → creates cysts making it resistant to chlorine

G → can survive up to an hour in chlorinated water

Toxoplasma (toxoplasmosis)

Prenatal infection can cause blindness and stillbirth

Flu-like symptoms otherwise

Spread through cat feces and/or undercooked foods (meats specifically) (like listeriosis, you cannot have deli meats, etc)

Especially a big problem for pregnant women/people

Prions

BSE/CJD (bovine spongiform encephalopathy, Creutzfeldt-Jakob’s Disease)

Infectious agent made of protein that disrupts neural tissue (creates holes in brain like a sponge)

Symptoms: depression, loss of motor function/coordination, dementia, death (these can take a while to pop up, 10-20 years, but once they do you’re dead within a year)

Outlawed to feed beef to cattle → stopped the spread of BSE