Test 4

Want drugs that harm the microbe, not the human host

• portals of entry
• adherence infection and growth
• penetration of host
• damage of host cell
• portals of exits

infectious dose # of microbes needed to cause infection in 50% exposed

Characteristics that allow a microbe to cause disease

• Penetration of mucous membrane
• Penetration of the skin

Alow microbes bind to specific cell types. Bind receptors naturally found on certin cells

• Hiding within host cell
• evasion of complement
• evasion of phagocyotsis
• avoiding Abs
• exoenzymes
• AG variation

using host nutrients, direct damage by invasion. producing toxins, inducing hypersensitivity reactions

Lethal dose for 50% exposed - A messurement to compare potency of different toxins

Are part of the outer portion of the cell wall G- bacteria only liberated when bacteria dies

• Host target tissue is the nervous system
• Result paralisis
• Ex. Batululinum toxin blocks transmisson to muscle

• Toxins that forms in the cell membrane
• host target tissue: cell membrane phospholipids
• Results unstable host cell membrane cell lysis
• Ex. C. difficile

• Targets T cell receptors
• results Triggers massive cytokine release too much information
• Ex. Staphylcoccus TSST

can block small capillaries

Blood, CSF, Bladder, muscle, solid tissue, lungs

scientific study of disease

describes how a disease develops; how a microbe causes disease

the degree to which a microbe can cause disease

Cause of disease

cause disease in anyone heathy person

weakend form prior infection like bronchities

weaker pathogen causes disease in a weak host

HIV positive, cancer pts, Chrones illness, malnurished

Is the invasion or colonization of the body by pathogenic microorganisms.

occurs when an infection results in any change from a state of health

develops rapidly lasts a short while - influenza

develops slowly body reaction less severe continue for a long time

• remains inactive for some time then becomes active produce symptoms of disease
• ex shingles

Carry the diesase but show no symptoms

Toxic inflammatory condition arising from the spread of microbes

presence of bacteria in the blood

presence of viruses in the blood

presence of toxin in the blood

blood posioning, multiple pathogens in the blood

• Incubation period
• Prodromal period
• Period of illness
• Period of decline
• Period of convalescence (recovery)

Humans, water, Animals, enviornment

• Animal to human
• Ex: boubonic pleague - rats

• Contact transmission (direct or indirect)
• Droplet
• Vehicle Transmission (one sorce infects many people)
• Waterborne
• Foodborne
• Airborne
• Vector (insects)

An object that can spread disease

Microbe carried on the surface of the insect

Microbe replicates with in the insect

• Hospital aquired infection
• EX: most common UTIs

• Misplaced own flora
• Hospital enviornment
• Health care workers

• Disease that has an increased number of infections over the past 20 years
• EX: Avian flu (H5N7), Swine flu (H1N1)
• Climate fluctuations and changes

Number od disease causes

number of deaths from a specific disease

Number of new infections in a certin time period

Number of people sick with a disease (new and ongoing) in a time frame

Always present in a population

Sudden increase of disease in one population

World wide

Graphs

Analyzes diease treands or outbreaks.

Tests a Hypothesis

Reports specifi cases of disease outbreak

enhance benifit to pt

• Augmentin- Amoxi and Clavulanic acid
• TMP-SMZ- Tri meth Sulfa

• Inactivation- cleaves beta lactam
• Alteration of target site- durg no longer binds
• Decrease uptake of drug - blocks entry
• Increased elimination of drug - efflux pumps

Sharing of plasmids, Transduction, Transformation

• Inhibit cell wall synthesis (Peptidoglycan)
• Inhibit protein synthesis (ribosome death)
• Injure plasma membrane (polymixin B)
• Inhibit nucleic acid synthesis
• Inhibits synthesis of essential metabolites (folic acid)

• Bacitracin (attacks synthesis of cell wall)
• Polymyxin B (injures plasma membrane)
• Neomycin (blocks protein synthesis)

• Amoxicillin
• Penicillin
• Ampicillin
• Methicillin
• Augmentin
• Vancomycin - treat MRSA only G+

• Streptomycin- TB
• Tetracycline (doxy)
• Ethromycin (used if Pts are allergic to penicillin)

Polymyxin B (Topical)

• Rifampin
• Ciprofloxacin

TMP-SMZ trimethoprim sulfamethoxazole

• Amphotericin B
• Miconazole
• Fluconazole

• Acyclovir- treats herpes/ shingles
• AZT- treats HIV

• Tamiflu
• Amantadine and Rimantidine

Antimicrobial IFN alfa and INF beta cause cell to degrade mRNA which blocks viral replication

Antiprotozoan drug interferes with anaerobic metabolism treats amoebic dysentery, giardia, and some anaerobic bacteria.

Used to treat Malaria (Plasmodium)

Broad spectrum antihelminth inhibits formation of microtubles in the cytoplasm which blacks absorption of nurtrients by the parasites: Trichinellosis, pinworms, roundworms

• Capsomere
• capsid
• nucleocapsid
• nucleic acid
• envelope
• Virion

no lipid enevlope many flat sides hard to kill

Easier to kill with disinfectants, Lipid envelope

• Entry by pinocytosis or fusion
• Uncaoting
• Release by budding or lysis

• Animals:
• in cell culture
• in embryonated eggs
• in living animals
• Bacteriophage:
• in a host cell lawn

Viruses that infect bacteria

Always a productive infection = new viruses produced

• Attachment Via spike proteins on virus bind to specfic proteins on host cell
• Penetration injection of DNA genome into host bacteria
• Biosynthesis DNA and protein are produced
• Maturation Spontaneous assembly
• Release through cell lysis caused by the enzyme Lysozyne

• Doesn't kill host.
• Attachment and entry DNA intergrades into host chromosome
• Bacteria replicates normally; non productive infection

• When the phage integrates into the bacterial chromosome it brings new genes to the bacteria
• Effect: may incode toxins
• EX: Clasrtidium botulinum

• Attachment with spike proteins
• Entry by pinocytosis or fusion
• Uncoating DNA is released into the host cell
• Biosynthisis
• Maturation
• Release by budding or lysis

• Short duration Virus is released right away
• EX: Common cold

• Virus remains in tissue
• EX: Measeles

• Consistant virus is continually released from host
• EX: hep B

• Remains dormant in host and can reactivate later
• EX: Herpes

Random point mutations in the H and N genes (small changes)

• Occurs when there is genetic recombination between 2 different influenza strains causes new epidemics
• EX: N1H1 Swine flu

• yest
• mold
• mushrooms

Cell wall made of chitin

The study of Fungi

Visable fungal growth, vegetative structures

Multicellular filaments

Mass of Hyphae

• 2 morphologies
• Role in desease: Grows in soil as a mold but once inhaled it grows as a yest
• EX: Pnenomia

• Zygomycota
• Ascomycota
• Basidiomycota
• Deuteromycota

result from the fusion of 2 nuclei from 1 (+) and 1 (-) mating strain of the same species

• Make clones of the parent
• Conidiospore not inclosed
• Sporangiospore inclosed clusters

Whole body is effected

• underneath the skin
• EX: Rose gardener's disease

• Caused by dermatophytes that make keratinase degrades protein keratin in skin and nails
• Attacks the feet
• EX: Athletes foot

EX: Pneumocystis in AIDS pts

• Mostly aquatic living top few meters of water
• Simple eukaryotic photoautotrophs
• Fix CO2 into organinc carbon released as O2

• Algae and Fungi living in a mutualistic symbiotic realationship
• Algae preforms photsynthesis and feeds both organisims
• Fungi attaches both to a rock or tree and provids protection

• Dinoflagellates/ Plankton: Alexandrim, large number of algae cause the red tide causing paralytic shellfish poisoning
• Domic acid Intoxication: Illness due to toxin ingestion casues neurological disease in people kills marine birds and sea lions

Inhibit water and soil all are unicellular orgainisms

By means of motility

Growing/feeding stage

Protective form, usally shed in feces.

• 2+ flagella
• EX: Giardia
• Disease: Trophozoites (diarrha)
• Transmited: fecal-oral

• Obligate intrcellular parasites
• Cause of chronic diarrhea in AIDS pts

• Pseudopodia
• EX: Entamoeba histolyitca
• Disease: Amoebic dysentery
• Trasmited: Fecal-oral

• Non motal
• EX: Plasmodium causes Mararia
• EX: Toxoplasma gondi causes toxoplasmosis
• EX: Cryptospordium causes Diarrhea
• Transmitted: Insect

• Motility: Cilia
• EX: Balantidium coli
• Disease: dysentery
• Transmited: fecal-oral

• Motility: Flagella
• EX: Trypanosoma cruzi causes chagas disease
• EX Tryponosoma brucei causes africal sleeping sickness
• Transmited: Insect bites

Male and female in seperate oragnisms

Male and female in 1 organism Produce large numbers of eggs that are infectious.

Host where the organism undergoes sexual reproduction

Host where the organism only reproduces asexually

multicellular animals free living ot parasitic have organ sysmtems have complex life cycles

• Class: Cestode
• EX and disease: Flat worms and Taenia solium (pork tape worm) Cysticerosis Cysts in brain and muscles
• Class: Termatodes
• EX and Diseases: Flukes and schistosoma- Schitosomiasis

• EX: pin worm, roud worm, hook worm
• Diseases: hook worm infection