microbio final new material

how important are waterborne diseases and how do we control them?

everyone needs water, we control them by having clean water and good wastewater treatment

what are coliform bacteria and how do we test for them

Rod shaped Gram – bacteria, their presence means that there is infected water. Test by sampling, incubation with special media

cholera: symptoms, name of pathogen, treatmenr

-        vibrio cholerae, cholera toxin

o   Messes with electrolyte balance in gut

o   Invasive, multiplies and invades intestine quickly

o   Rice stool, lose a bunch of water

o   Antibiotics can treat this, need supportive care

legionellosis

o   Legionella pneumophilia

o   Causes pneumonia

o   Passed through warmer water, older people more susceptible to it

typhoid

o   Salmonella enterica (typhi)

o   Fever, rash, ulcers in the intestine

• Can go into dormant state and spread

antibiotics for food poisoning

how can food be a disease vehicle, and how can we prevent foodborne illness

If it is not taken care of properly (refrigeration) or cooked properly

food poisoning vs food infections

Food poisoning is caused by the toxin, bacteria does not need to be alive. Food infection is the bacteria itself

staphylococcus

o   Produce enterotoxins

o   GI symptoms

o   S. aureus

• Grow slowly with proper storage, enterotoxin is heat stable

*food poisoning

clostridial

o   Clostridium perfringens

•   Causes gas gangrene

•   Also food poisoning

• Grows quick at room temp, usually from meat

o    clostridium botulinum

• Can be fatal

*food poisoning

slamonellosis

o   Salmonella

o   Caused by common food, chicken or handling reptiles

o   Resolves itself in 2-5 days

*food infection

e.coli

o   Some strains cause food infection, some toxins

o   Shiga toxin causes hemorrhaging in your intestines (damaging)

o   The strains that carry this toxin can go to the kidney and cause kidney failure

*food infection

campylobacter

o   Very low ID50

•   Fewer than 200 bacteria cause this infection

o   Mostly pork, shellfish, and poultry

•   Almost 90% of raw chicken is contaminated

o   People who take antacids are more susceptible, because the stomach acid kills it off

*food infection

listeriosis

o   Listeria monocytogenes

o   More serious of a food infection

o   Can lead to bacteremia (cause meningitis)

• Cause death

o   Found on deli meats (why pregnant women should not eat)

•   Also in raw milk

*food infection

what are diseases transmitted by animals called, what steps to control these

Zoonotic diseases, vaccinating animals, not being around wild animals

rabies

o   Caused by rhabdovirus

-  At least 3000 years old

o   Fatal once it is disseminated into the brain

-  Takes about 72 hours → window for vaccinations

o   About 3000 deaths from rabies worldwide per year

o   Symptoms

- Goes to your brain, makes you very angry

-  Mood changes, increases aggression

-  Trouble swallowing/fear of swallowing

 

typhus

o   Rickettsia prowazekii

o   Transmitted by fleas, infects bite

o   Symptoms: fever, headache, rash in armpits

o   Causes damage to CNS, kidneys, heart

o   Antibiotics to control

*rickettesial disease

spotted fever

o   Rickettsia ricketessi

o   Transmitted by tog tick

o   Incubation is 3-12 days

o   Headache, fever, rash, GI problems

o   Treatment only works early

*rickettesial disesase

ehrlichiosis

o   Ehrlichia chaffeensis and enrlichiaewingii

o   Rash, symptoms like spotted fever

o   From ticks, symptoms early

*rickettesial disease

Q fever

o   Caused by coxiella burnetti

o   Transmitted through animal placenta (seen in rural areas)

o   Symptoms – flu-like, most can get over it

o   Antibiotics need to be started early to prevent heart damage

-        Lyme disease

*arthropod transmitted

Lyme disease

o   Borella burgdorferi -> spirochete

o   Transmitted by ticks

-  Bullseye like rash

o   Headache, achiness, fatigue

o   Treatable with antibiotics early

*arthropod disease

Flaviviruses

o   Arboviruses

-  Yellow fever

-  Dengue fever (some vaccine)

- Zika virus (tends to be mild, can cause fetal death/abnormalities)

o   Transmitted by mosquitoes

o   Cause range of severity of symptoms

-  Mild to fatal

*arthropod transmitted

West Nile fever

o   From mosquitoes

o   Can cause encephalitis

o   Mild-fatal

o   Mosquito control to prevent

*arthropod transmitted

Plague

o   Bacteria -> yersinia pestis (antibiotics)

-  Fleas, bite humans to transmit

o   Bubonic plague

-  Gets in lymph and produces buboes

·       Swollen lymph nodes, turn black, burst and cause rapid death

o   Pneumonic plague

-  Transmissible person to person

-  Coughing

·       Severe pneumonia that causes fast death (24 hr)

*arthropod transmitted

anthrax

o   Bacillus anthracis (survives in the soil)

o   Produces endospores

o   Cutaneous anthrax

- Sore on your skin

-  Not fatal, treated with antibiotics

o   Anthrax of the lungs

- Severe pneumonia – high mortality rate

-  Can be treated with antibiotics

·       Transmitted by inhaling spores

*soilborne

tetanus

o   Spasmatic paralysis

-  Can be so bad it breaks someone’s bones

o   Clostridium tetani – anaerobic (puncture wounds)

-  Not particularly invasive

-  Toxin does the damage

o   Vaccine

*soilborne

Gas gangrene

o   Clostridium perfringens

- Anaerobic

o   Invasive tissue pathogenesis

o   Ferments and produces hydrogen gas (can hear it crackling under the skin)

o   Antibiotics

o   Exposure to hypobaric oxygen as treatment

o   amputation

*soilborne

*oitis media, mastoiditis, sinusitis*

Upper respiratory infections – bacterial

o   Middle ear, sinuses, mastoid cavity all connected

o   Ear infection (no antibiotics unless it lasts a long time)

pharyngitis

Upper respiratory infections – bacterial

o   Sore throat

o   Group A or group C strep mostly

o   About 57 different strains of strep (treat with antibiotics)

o   Can migrate to the heart, can also cause scarlett fever

scarlet fever

Upper respiratory infections – bacterial

o   Caused by strep A – can occur from strep throat

o   This strain of strep secretes a toxin

o   Symptoms

-  Rash, redder in armpits, groin, fever and sore throat

o   Treat with antibiotics

diptheria

Upper respiratory infections – bacterial

o   Corynebacterium diptheriae

o   Symptoms

- Localized plaque called pseudomembrane, sore throat, fever

- Toxin that disrupts protein synthesis

-  Toxin can cause severe, life-threatening death

o   Antibiotics, antitoxins, vaccination

Rhinovirus

Upper respiratory infections – viral

o   Colds, 100s of serotypes

parainfluenza

Upper respiratory infections – viral

o   4 types

o   Serious in infants

o   15-20% of nonbacterial hospitalizations

o   Symptoms

-  Croup (in babies), pharyngitis that can lead to secondary infection

community acquired pneumonia

Lower respiratory infections – bacterial

o   Typical

-  Caused by aspiration of pathogens

-  Streptococcus pneumoniae

- Antibiotics

o   Atypical

-  Walking pneumonia

-  Chlamydophila and mycoplasma pneumonia, sick but not hospitalized

tuberculosis

Lower respiratory infections – bacterial

o   Mycobacterium tuberculosis

o   About 2 billion people infected, not in America

o   Stages of infection

-  Primary ^→ lungs infected, bacteria taken to lymph, tubercules form (dormant)

-  Secondary → breakdown of old tubercules, release of bacteria (symptoms return)

o   Treatment takes more than 6 months

-  Triple or double antibiotic therapy

-  Direct observed therapy (have person observe you take ur meds)

-  Antibiotic resistance is a huge problem

pertussis

Lower respiratory infections – bacterial

o   Bordetella pertussis

o   Whooping cough, 80-100% of people exposed will get it

o   Produces tracheal toxin that immobilizes ciliated cells – cannot expel mucous

o   Stages

-  Catarrhal stage – runny nose, sneezing, malaise

-  Parosymal stage – lasts 2-4 weeks, persistent cough, severe whooping sound (inhalation)

-  Convalescent – symptoms decrease

o   Treatment

-  Vaccination – dTaP

-  Antibiotics if early

Influenza - airborne

• three types → A, B, C

• enveloped RNA virus - mutates easily

• concerns about recombination - bird flu

• symptoms → fever, chills, cough (can become lethal)

respiratory syncyrial virus (RSV)

airborne

• common in children, very contageous

• severe in immunocompromised

• symptoms - cold, cough

• treatment - observation, oxygen

meningitis

airborne

• bacterial

  • medical emergency, fatal if untreated

  • death or brain damage

  • headache, stiff neck → run to hospital

• viral (aseptic)

  • with other viruses -> enterovirus, mumps, herpesvirus

  • not as severe

• chronic

  • caused by forms of tuberculosis

measles

airborne

• single stranded RNA virus

• extremely contageous

• two forms

  • rubeola (5 days measles)

  • hard measles (7-18 days)

• restricted to humans

• usually seen in preschool children who are not vaccinated

• symptoms

  • respiratory → spread to lymph

  • risk of secondary infection

  • Koplick’s spot → rash in mucus membranes of mouth

• vaccine

rubella

airborne

• mild or assymptomatic

• pregnent women → congenital abnormalities in fetus

• vaccination

smallpox

airborne

• eradicated worldwide

• only vaccinated if in military

• causes vesicular rash

  • death from overwhelming viral load

mumps

airborne

• vaccine → you can still get it when vaccinated

• causes inflammation of salivary glands

  • can cause male infertility

chickenpox/shingles

airborne

• varicella-zoster virus

• spread through secretions of respiratory tract

• will go latent, come out of latency and get shingles (nerve damage)

syphilis

direct contact

• treponema palladium

• spirochete

• treated by penicillin

• stages

  • primary: lesions (painless), swollen lymph nodes, 4-6 weeks symptomatic

  • secondary: 2-8 weeks after lesions disappear, infectious rash, ends with latency/rebounds

  • tertiary: reaches 1/3 untreated patients

    • 5-20 years after infection

    • spread to cardiovascular and nervous systems

• congenital → can be spread in 4th month of pregnancy

  • severe congenital defects/miscarriage

Gonorrhea

direct contact

• neisseria gonorrheae

• displays antigen variability - changes antigens on surface

• only 50% of cases get reported

  • many are asymptomatic

• resistant to penicillin, hard for adaptive immune system to respond

Chlamydia

direct contact

• non-gonococcal urethrivirus

• humans are resevoir

  • 5-20% infected

  • many men show no symptoms

• healed with antibiotics

Herpes simplex virus type 2

• HSV 1 = cold sore, HSV 2 = genital herpes

• goes latent, only transmittable when symptoms present

• painful genital lesions

• treat with antivirals but cannot fully get rid of it

• can be transmitted to baby at birth

HPV (human papillomavirus)

• causes warts

• 70 genotypes

  • type 16 known to cause cancer

• treatment

  • surgical removal, cryotherapy

  • vaccination

    • 80-90% of cervical cancer caused by HPV

bacteria in meats

• bacteria used to cure meats like salami or ham

bacteria in coffee and chocolate

• beans are fermented after harvesting

  • short or long time