Lecture 32, 12/3; Viruses, Immunology

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• • Medically important human viruses
• • HSV-1, HSV-2 → herpes, oral and genital
• • RSV → respiratory sincicial virus. Mom can give it to the baby.
• • EBV → mono and burkettes lymphona
• • VZV → chicken pox and shingles
• • HPV → human papiloma virus. Causes warts. Some strains are associated with cervical cancer. (this is why Guardisil is popular)
• • Adenovirus → upper respiratory infections, not a cold
• • HAV → Hep A virus. Fecal/oral → contaminated water/food. There is a vaccine for it.
• • HBV → Hep B virus. Blood borne or semen. Linked with liver cancer. There is a vaccine for it.
• • HCV → Hep C virus. Similar transimission to Hep B. Used to be called transfusion disease. No vaccine.
• • Rotavirus → severe diarrhea in babies and toddlers. Rotateq combats this disease.
• • Rubella virus → German measles
• • Variola virus → supposedly eradicated. Smallpox
• • Rabies virus → rabies. Bullet shaped virus. Most deadly.
• • Measles virus → MMR takes care of it
• • Influenza → old get vaccinated. Hypermutability – changes very quickly. This is why you need a flu shot every year.
• • Hantavirus - Navajo flu → Comes from little white mice.
• • CMV – Cytomegalo virus → Babies, toddlers, and AIDs patients are susceptible.
• • Rhinovirus → common cold, 120 different strains (that is why there is no vaccine).
• • Echo/Coxsackle viruses - Noro virus → Causes gastroenteritis. Cruise ship disease.
• • Mumps virus → can move to testicles in guys. MMR vaccine takes care of it.
• • St. Louis Encephalitis virus (SLE) → mosquito borne
• • West Nile → mosquito borne
• • HIV-1 and HIV-2 → takes out all T helper cells. Allows for opportunistic disease to come in.
• • HTLV-1 and HTLV-2 - human T cell lymphoma viruses → Can cause cancer.
• • AID’s related infections – sheet from handout showing diseases AID’s patients get with time.
• o Bacterial skin infections are one of the first things you see.
• o Thrush comes in (usually a good indicator of AID’s)
• o Severe athletes foot
• o PCP, histo, herpes, crypto
• • IMMUNOLOGY
• o Winter viruses are typically airborne
• • 1st line of defense – Mechanical factors
• o lysosymes – good against gram (+).
• o Organisms can’t go through the skin EXCEPT for rabbit fever
• o Mucus is sticky and holds organisms
• o Normal flora – prevent pathogens from colonizing
• • Second line of defense - Cellular factors
• o If disease comes into bloodstream white blood cells will come to do phagocytosis (discovered by Meintchnekoff). Interferon was initially up to 10,000$ a shot.
• o Inflammation – heat, redness, swelling, pain. This is the bodies way of localizing an infection.
• • Third line; antibody formation. Takes 10-14 days
• o Acquired immunity
• • Types of acquired immunity
• o Active immunity – we form the antibodies (long lasting)
• • Artificially acquired - vaccines
• Naturally acquired – infections
• • Acute or sub-acute
• o Passive immunity – someone else is forming the antibodies
• • Artificially acquired – HBIG
• • Immune globulin – immediate protection but does not last long (about a month). They are preformed antibodies.
• • Naturally acquired – HgG and IgA
• IgG is given from the mother to baby across the placenta. IgA is from mothers milk – it coats intestine of baby and prevents diarrhea in baby. Rototeq can cause this diarrhea.
• • Classes of antibodies
• o “Y” usually represents antibodies
• o IgG – the most important one, we have the most of this in our blood. 80-85% of all the antibodies we carry is IgG. Major protective antibody in blood. If you run into an antigen it is IgG that will probably attach to it. It is also the one that comes from mom to baby over placenta.

Lecture 31, 11/30; Vectors, Toxins

Here's the audio.

• Opening
o Monday – pass in AID’s Week reflection paper
o AID’s cases have been about 40 mil. For the first time AID’s has decreased.
o Autclave 121C, 15 psi, 15-30min
o Filtration
o Sab-dex=molds
o EMB, McKoncey – gram (-) rods
o 3:20 what azide does?
o Ent fecalis – always ferments – nothing oxidated
o 100 colonies on a plate → 10^5 → positive for UTI

• • Bacteria
• o Salmonella typhi – typhoid fever
• o Shigella dysenteriae - dysentarea
• o Vibrio cholerae - cholera
• o Campylobacter jejuni - gastroenteritis
• o Escherichia coli
• • protozoa
• o entamoeba histolytica – amoebic dysentary
• o giardia lamblia - giardiasis
• o cryptosporidium parvum - cryptosporidiosis
• • Viruses
• o Hepatitis A virus (HAV) – fecal, oral
• o Poliomyelitis virus (PMV) -
• o Coxsackie/Echo/Norwalk – Norro (cruis ship disease)
• • Bioremediation – pseudomonas
• • Sewage treatment – bacteria are involved here
• • Food poisoning
• • “Infectious Disease” handout – mode of transmission
• o Mode of Transmission
• o Contact infection – STD’s
• o Droplet infection
• o Phomites are inanimate objects.

• • Vectors

• o Insects that move the organism from one place to another. Ex. Flies, mechanical vector → cholera
• o Biological vectors – growth stage is in the vector. Lyme, malaria, west Nile.
• • Portal of entry
• o Elementary track
• o Mom → baby = vertical transfer. Ex. AID’s, psyphylis, genital herpes
• • If you’ve seen the antigen you’ve got antibodies.
• • Typhoid Mary – Salmonella typhi
• o Could have carried in gall bladder. Found in poop → no hand washing
• • Study pathogens from two standpoints: transmission, how does it cause the disease – virulence factors
• • Virulence factors – how do they cause disease
• o invading tissue – invasive factors OR
• o production of toxins – toxigenic factors
• • Capsule – inhibits phagocytosis
• o Strep pneumonae
• o Klebsiella pneumonae
• • Pillis
• o Neisseria gohnerrhea
• o Whooping cough – bordetella pertussis
• • Highly uronidase (the spreading factor) – sometimes its structure sometimes its enzyme or secretion. It is an enzyme that breaks down highly uronic acid (this is whats in tissue that holds cells together, if this is broken down the organism spreads through the tissue)
• o Usually think of staphs and streps
• • Coagulase – Coagulase positive → staph aureus.
• • Lukasiden – staphs and streps have a secretion that kills white cells. An accumulation of this dead white blood cells is puss.
• • Hemolysin – break down red blood cells. Alpha and Beta hemolysis can only be seen on blood agar. Alpha is incomplete, Beta is complete. Streptococcus pneumonae is an alpha. Strep pyogenes - complete hemolysis.
• • Toxins
• o Exotoxins – from some gram (+). More lethal.
• o Indotoxin – from gram (-)
• • High fever = gram (-) infection
• • Classical exotoxins
• o Corinii
• o Tetani
• o Botulinum
• • Staph aureus has an enterotoxin (under exotosin category). It affects the intestines. That enterotoxin is what causes staph food poisening.
• • Shigella dysentari (gram -) – has an endotoxin
• • Immunology
• o Resistance (much broader) vs immunity (specific antibodies for a disease)
• o Antigen – a substance, usually injected, producing protective proteins called antibodies. Vaccines are suspensions of antigens.
• o Immunoglobulin (Ig’s) – new name for antibodies (protective proteins that are formed in response to antigens).
• o An antigen has size - molecular weight of more than 10,000. It has to have chemical complexity. Proteins are very good antigens. Lipids → no . . . nucleic acids → no.
• o Lupus – your respond to your own DNA