Micro5 Final Exam

Describe Food Poisoning

-Skin contact transmission - heat stable enterotoxins (sAgs) Sudden onset (30min-8hrs) • Nausea, diarrhea, vomiting, abdominal cramps • Self-limiting, complications are rare (1-3days)

Dental Caries (Tooth Decay)

-Streptococcus mutans • Metabolizes sucrose • Makes dextran/glycocalyx (biofilm) • Acid damages enamel Sucrose increases the risk of cavities because it interacts with the bacteria to produce acid that damages the enamel and eventually creates cavities and holes in teeth.

Diagram an antibody (with heavy chains, light chains, and Fc (stem) region) and show where it interacts with its epitope.

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Explain how millions of unique, specific antibodies and TCRs can be generated from only a few genes.

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Explain what is meant by the humoral and cellular branches of the adaptive immune system. What kind of pathogens are targeted by each branch?

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Explain why each B or T cell can only make one type of antibody or TCR.

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Explain how naïve cytotoxic T cells (CD8+) are activated to become CTLs and describe the function of CTLs

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Give a few examples of how bacteria use enzymes to evade host defenses and spread within the host.

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Give a few specific reasons why the secondary immune response to an antigen is faster and stronger than the primary immune response is.

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How and why do CTLs kill other host cells? How and why do NK cells kill other host cells? What are the differences between these two killer types of cells?

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How do naïve B cells get activated (T-dependent and T-independent) and what happens once they are activated?

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List and describe the 5 different immune defenses that antibodies can do once they bind to their epitopes.

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Refresh your memory on humoral vs. cellular immunity. How do helper T cells, cytotoxic T cells, NK cells, and B cells fit into these two classes?

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Know the epidemiology and etiology of the bacterial and eukaryotic diseases discussed in lecture and in your classmate's reports

...blank but forget classmates reports just know the bacterial and eukaryotic diseases which will follow after this slide.

Explain the difference between an antigen and an epitope.

An epitope (also known as the antigenic determinant) is that part of the antigen to which antibodies bind. While the antigen evokes the antibody response in the host, the antibody doesn't bind to the entire protein, but only to that segment called the epitope

Some pathogens can vary their antigens (antigenic variation). Why is this advantageous for the pathogens?

Antigenic variation- allows some pathogens to basically "change clothes" in order to hide from the immune system. Advantageous because it prevents the pathogen from getting targeted by the immune system.

Candida Albicans

Normal flora in 40-80% of people Mouth, Vagina, GI Tract Opportunistic infection Yeast infection Thrush Diaper rash Dimorphic Life cycle

Infectious Disease

A disease in which pathogens invade a susceptible host and carry out at least part of their life cycle in the host. Ex: HIV/AIDS, Flu, E. coli

Signs

Observable and measurable, such as fever, rash, paralysis, tissue changes, weight gain/loss, blood pressure, etc.

Explain the basic actions of A-B toxins, membrane-disrupting toxins, and superantigens

A-B Toxins: A part is the active(enzyme) component & the B part is the binding component binding. Some gram negative make genotoxins. Genotoxins cause a break in the Eukaryotic DNA by causing a mutation and disrupting cell division and can also lead to cancer Membrane-Disrupting Toxins: Cause lysis in the host cells by disrupting plasma membrane. Some do this by forming protein channels in the membrane, other may disrupt phosppho lipid portion of the membrane. They also kill white blood cells called leukocidins. Superantigens: Antigens that provoke a very intense immune response, they are bacterial proteins that combine with a protein on macrophages, nonspecifically stimulates the proliferation of immune cells called T cells. When stimulated, T cells are to release enormous amounts of cytokines, which are small molecules produced by various body cells, that regulate immune responses and mediated cell to cell communication.

Explain how and why bacteria adhere to host surfaces.

Adherence is a necessary step in pathogenicity The attachment between pathogen and host is accomplished by means of surface molecules on the pathogen called adhesins or ligands that bind specific to complementary surface receptors on the cells of certain host tissues

Explain what a Type Three Secretion System is and give examples of what effectors can do to the host cell

Also known as (T3SS). This is a protein appendage found in several gram-negative bacteria used to inject "effectors" into host cells. Can cause tissue digesting enzymes, kill cells, secrete various toxins, scavenge iron, and take over cellular functions.

Define the term antigen. Antigens are usually which type(s) of biological molecule?

Any substance that causes the body to make an immune response against that substance. Antigens include toxins, chemicals, bacteria, viruses, or other substances that come from outside the body Antigens are usually proteins

to practice connecting all the little details into the big picture: "choose your own microbial adventure": using virulence factors we learned, describe the path that a hypothetical bacterium could take from entry to establishment of disease to exit.

Blank on purpose. This was on the study guide.

Be prepared to describe various virulence factors' roles in immune evasion, pathogenesis, and/or the signs and symptoms of the particular diseases caused by these bacteria.

Blank on purpose. This was on the study guide. Referring to slide 27.

Describe the various diseases caused by each of the bacterial agents. Epidemiology & etiology of each.

Blank on purpose. This was on the study guide. Referring to slide 27.

whooping cough (pertussis)

Caused by Group A strep Bacteria -Bordetella pertussis (G negative rod) • AB5-type exotoxin • Cold-like symptoms, followed by severe cough, spasms, vomiting • Pneumonia, seizures & encephalopathy • Droplet transmission - highly infectious • Young children at highest risk • DTaP vaccine, antibiotics

Necrotizing fasciitis

Causes by group A strep bacteria ~1000 cases/yr • Invasive, extremities • Virulence factors degrade tissues • 25-40% fatality rate • Sudden onset • Pain, swelling, redness, fever • Nausea, vomiting, fever, malaise • Antibiotics, surgery

Streptococcus pyogenes (Group A Strep)

Causes strep throat, Toxic shock syndrome, Acute rheumatic fever, Impetigo, Necrotizing fasciitis, Scarlet fever. Streptococcal Virulence Factors: -Protein F • Streptolysins • SpeA or SpeC • SpeB • M protein • Hyaluronic acid capsule • Protein G • C5a peptidase

What is clonal deletion and how does it help prevent autoimmunity?

Clonal deletion is the removal through apoptosis of B cells and T cells that have expressed receptors for self before developing into fully immunocompetent lymphocytes. This prevents recognition and destruction of self host cells, making it a type of negative selection or central tolerance.

What is a clonal selection and how does it help the body fight the particular microbes it is exposed to?

Clonal selection is a process proposed to explain how a single B or T cell that recognizes an antigen that enters the body is selected from the pre-existing cell pool of differing antigen specificities and then reproduced to generate a clonal cell population that eliminates the antigen.

What is the cause or causes (etiologies) of: Covid-19

Contact, Droplets, Airborne (Outdoor transmission unlikely), Contact with fomites possible, but not thought to be a major way that COVID-19 spreads

Know the 3 kinds of antigen-presenting cells, their role, and the differences between them.

Dendritic cells- A type of antigen-presenting cell characterized by long fingerlike extensions; found in lymphatic tissue and skin. Macrophages-A phagocytic cell; a mature monocyte there are also free and fixed macrophages. Free macrophage (wandering macrophage) A macrophage that leaves the blood and migrates to infected tissue. Fixed microphage- A macrophage that is located in a certain organ or tissue (such as the liver, lungs, spleen, or lymph nodes) also called a histiocyte. B-cells also called B lymphocytes are a type of lymphocyte that differentiates into antibody-secreting plasma cells and memory cells.

Explain how some bacteria can evade phagocytosis and complement.

Depending on the bacteria, this can be done in 4 ways. Stealth (hide from phagocytes) prevent phagocytosis (by using capsules, antigens, enzymes), control (enzymes, proteins that kill phagocytes or reduce function), and survival inside of phagocytes (using protective coats and enzymes)

Amanita spp

Destroying Angels - Amanita bisporigera & ocreata Death caps - Amanita phalloides - amatoxins (ingestion) - No anti-toxin - death within 3-5 days - mycorrhizal with oaks and pines - vomitting, diarrhea, kidney/liver failure

Summarize clonal deletion.

During development, lymphocytes with receptors that bind to self-antigens are signaled to die (by apoptosis). (following from slides) A single progenitor cell gives rise to a large number of lymphocytes, each with a different specificity THEN removal of potentially self-reactive immature lymphocytes by clonal deletion. -Why is it important? -Which lymphocytes are deleted?: B Cells -When does it happen?

Ascaris lumbricoides (Giant Roundworm of Humans)

Epidemiology: - Temperate/tropical regions with poor hygiene - 2 billion (~1/3 of world pop.) - Fecal-oral transmission (eggs) - No vector - No reservoir - Nightsoil • Pathologies: - Adults (12-20cm) in intestine can cause mechanical obstruction - Abdominal pain - Bowel perforation - Cough & wheezing from juveniles in lungs - Treated with Mebendazole

Trypanosoma cruzi

Epidemiology: - Mexico to S. America - 8-11 million people are infected Vector: Reduviid bug (aka. kissing bug) Reservoir: rodents, armadillos, dogs, cats • Pathologies: - Inflammation at bite - Swelling of the eyes - Fever, malaise - Enlarged Heart - Heart Failure

Echinochoccus granulosus (Hydatid Cyst Disease)

Epidemiology: S. America, N. Africa, Canada, Europe, Russia- (where dogs are used for herding sheep) • Canine tapeworm (dogs, wolves, coyotes) • No vector • Reservoirs: -Sheep, elk, caribou

Fasciolopsis buski (Intestinal Fluke)

Epidemiology: Southeast Asia • Females (2-7cm) produce about 25,000 eggs/day • Has no vector, but has three hosts • Abdominal pain, diarrhea, malabsorption, toxemia • Attaches to mucosa • Reservoir: Pig

Enterobius Vermicularis (Pin worm)

Epidemiology: Worldwide • Most common helminth in North America • No vector • No reservoir • Treatment: Mebendazole

Describe Staphylococcal Scalded Skin Syndrome (SSSS)

Exfoliative Toxins • Desmosome proteins • Fluid loss • Secondary infxns

Differentiate exotoxins and endotoxins. Why do only Gram-negative bacteria have endotoxins?

Exotoxins are proteins produced inside pathogenic bacteria, most commonly gram-positive bacteria, as part of their growth and metabolism. The exotoxins are then secreted into the surrounding medium during log phase. Endotoxins are the lipid portions of lipopolysaccharides (LPS) that are part of the outer membrane of the cell wall of gram-negative bacteria (lipid A; see Figure 4.13c).The endotoxins are liberated when the bacteria die and the cell wall breaks apart.

Symptoms

How a patient may feel, such as pain, discomfort, lethargy, nausea, dizziness.

Be able to interpret ID50 and LD50 data as we did in class.

ID50: Median infectious dose needed to infect 50% of the test population. Can be different depending on the portal of entry LD50: median lethal dose needed to kill 50% of the test population. This term most often used for toxins

Know the basic characteristics of the 5 classes of antibodies. Especially know which ones are most abundant in serum, bodily secretions, and which two classes are the best at agglutination.

IgM(best for agglutination)-very first ones to respond to the primary response to an antigen (found on B cell) IgA(best for agglutination)-most common; protect portals of entry; found in saliva, tears, breastmilk, mucus (float free in blood plasma) IgE-respond in allergic reactions/ parasite infections (float free in blood plasma) IgD-found on mature B cells (found on B cell) IgG-effective against antigens in secondary response; effective against toxins, viruses, and bacteria (float free in blood plasma)

Explain how the adaptive immune response starts, and how it involves the innate immune system.

Immature dendritic cells reside in peripheral tissues. Then dendritic cells migrate via lymphatic cells to regional lymph nodes. Finally, mature dendritic cells activate naïve t cells in lymphoid organs such as lymph nodes.

Noninfectious Disease

Include all diseases that are not caused by pathogens. Noninfectious diseases are generally caused by genetic or environmental factors other than pathogens, such as toxic environmental exposures or unhealthy lifestyle choices. Ex: Cancer, Alzheimer's, and Epilepsy, Diabetes

What is the cause or causes (etiologies) of: Strep Throat

Infection with a bacterium known as Streptococcus pyogenes, also called group A streptococcus.

Anisakis simplex

Japan, Pacific coast of South America, the Netherlands • Zoonosis • Extreme pain, vomiting within hours

MALARIA

Kills 1-2 million/year • Loss of productivity • Vaccines slow • Mosquito abatement • Swamps

Understand how and why some bacteria steal iron away from the host.

Like their human hosts, bacteria need iron to survive and they must obtain that iron from the environment. While humans obtain iron primarily through the food they eat, bacteria have evolved complex and diverse mechanisms to allow them access to iron.

Malassezia furfur

Lipophilic yeasts - live in/near oily areas Fungal enzymes inhibit melanin production Itchy, scaly, redness or pigment loss selenium sulfide (head&shoulders) ketoconazole & similar (topical forms)

Summarize clonal selection.

Lymphocytes that bind to foreign antigens proliferate, forming clones of identical B or T cells. (following from slides) A pool of mature naïve lymphocytes. Proliferation and differentiation of activated specific lymphocytes to form a clone of effector cells. -Why is it important? -Which lymphocytes are selected? Naïve B cells and T cells -When does it happen?

What is an MHC molecule? Which cell types express each class of MHC molecule, and why?

MHC molecules are Major Histocompatibility Complex. MHC class 1: in all nucleated cells. Presentation of endogenous antigens helps immune cells monitor if that cell is infected/cancerous. MHC class 2: only in special antigen-presenting cells (APCs) (dendritic cells, macrophages, B cells) →present exogenous antigens.

What does it mean that a pathogen has a preferred portal of entry? How can we observe this preference?

Many pathogens have a preferred portal of entry that is a prerequisite to their being able to cause disease. If they gain access to the body by another portal, disease might not occur Ex: Salmonella Typhi, produce all the signs and symptoms of the disease when swallowed(preferred route), but if the same bacteria are rubbed on the skin, no reaction (or only a slight inflammation) occurs.

What are the main portals of entry that pathogens use to get into our bodies.

Mucous Membranes: Respiratory, GI tract, Urogenital, Eyes Skin: Intact skin, Hair Follicles, and Sweat gland ducts Parenteral Route: Bites, injuries, injections, Surgery

Tuberculosis - "consumption"

Mycobacterium tuberculosis • Droplet transmission • Usually asymptomatic, latent infection • Bloody cough, fever, pallor, and wasting • 6-12 mos. rifampicin or isoniazid • Multi-drug resistance

explain how naïve helper T cells (CD4+) are activated and the three things that effector TH cells can do.

Naive CD4⁺T cells are activated in secondary lymphoid organs when an activated dendritic cell (DC) presents a cognate antigen in MHC class II The three things that effector Th cells can do are activate macrophages, help active cytotoxic (killer) T cells, and activate B cells to become plasma cells (mass-produce antibodies)

Ancylostoma (Hookworm)

Necator americanus & A. duodenale • Worldwide distribution • Intestinal or cutaneous • Creeping eruption (cutaneous larval migrans) • Prevalence=1.3 billion (2002) • Tx: albendazole, ivermectin

Penicillium spp.

Penicillium marneffei • systemic infection- inhalation of spores • Fever and anaemia similar to disseminated cryptococcosis • High incidence in SE Asia - almost entirely in HIV + (extremely rare in HIV neg.) • 10% of HIV+ in Hong Kong • Associated with bamboo rats • amphotericin B, itraconazol.

Major Groups of "True" Parasites

Protozoans: single-celled eukaryotes, EX: Malaria, Giardia, Trichomonas vaginalis Helminths: Multicellular Animals, Ex: Flukes, Tapeworms, Roundworms Ectoparasites: Multicellular Animals, Live outside the host, Ex: Ticks, Lice, Fleas

What are the various portals of exit that microbes can use?

Respiratory Tract Gastrointestinal Tract Skin Contact Blood Genitourinary Tract

Zygomycosis

Rhizopus spp. Produces ergot (poison) Bread, food mold Fast growing at low temps Rhinocerebral, cutaneous, pulmonary & GI forms General necrosis of infected tissue

Trypanosoma brucei

Rural poor areas of sub-saharan Africa • WHO estimated 300,000 cases in 2000 • Only 27,000 diagnosed • "Eastern" & "western " forms • Western - chronic, lasting years • Eastern - acute, death within months

Schistosomiasis (bilharzia)

Schistosoma mansoni, S. heamatobium, S. japonicum • 200 million infections worldwide (200+k deaths/yr) • Itchy rash, fever, chills, cough, and muscle aches • Africa, S. America, S. China, Middle East, SE Asia • Tx: praziquantel

Describe and distinguish between toxic shock and septic shock.

Shock refers to any life threatening decrease in blood pressure. Shock caused by bacteria is called septic shock. Gram negative bacteria is known to cause endotoxic shock. Like fever, the shockproduced by endotixins is related to the secretion of a cytokine by macrophages Toxic shock syndrome is a rare, life-threatening complication of certain types of bacterial infections. Often toxic shock syndrome results from toxins produced by Staphylococcus aureus (staph) bacteria, but the condition may also be caused by toxins produced by group A streptococcus (strep) bacteria.

List various diseases caused by Staphylococcus aureus and Streptococcus pyogenes

Streptococcus: Strep Throat, Impetigo, Toxic Shock Syndrome, Scarlet Fever, Acute Rheumatic Fever Staphylococcus: Carbuncle, Boil(Furuncle), Toxic Shock Syndrome, Food poisoning, Staph Infection, Impetigo

Describe Toxic Shock Syndrome Toxin

Superantigen (sAgs) --> cytokine storm --> TSS Signs/symptoms:- High fever - Rash - Diarrhea, vomiting - Confusion - Headache - Muscle aches - Skin peeling off 1 week later

Teniasis

Taenia solium & T. saginata • 1000+ cases/yr US • Prevelance = 50 million worldwide • Mexico, S. America, Asia • abdominal pain, weight loss • Cysticercosis on the rise

Briefly explain the concepts of self and non-self in immunity

The antigens on your own cells are known as self-antigens, while those that do not originate in your body are called non-self antigens. Self-antigens are present on all your cells, but they're particularly important in blood cells. You can only receive a blood transfusion from a donor with the same type of antigen.

Describe the typical stages of an infectious disease, from incubation period to period of convalescence

The incubation period (no signs or symptoms), Prodromal period (mild signs or symptoms), Period of illness (most severe signs and symptoms), Period of Decline (signs and symptoms), and Period of convalescence.

What happens to a macrophage when it gets activated?

Their motility and phagocytic capabilities are greatly increased when they are stimulated to become activated macrophages. This activation can be initiated by ingestion of antigenicmaterial. Other stimuli, such as cytokines produced by an activated T helper cell, can further enhance the capabilities of macrophages.

What do B cells and T cells have in common, and where do they each mature/develop?

These cells are involved in adaptive immunity. They are a type of lymphocytes. The cells are nucleated and motile. Both protect the body's immune system and help fighting infections. T and B lymphocytes are also similar in that each cell only expresses one type of antigen receptor. B cell development starts in the bone marrow (BM) and continues in the spleen to final maturation Precursors of T cells migrate from the bone marrow and mature in the thymus

RIngworm

Trichophyton rubrum & tonsurans Dermatophytes Keratinophilic filamentous fungus Contact transmission also, athletes foot, jock itch

Coccidioides

Valley Fever Endemic in deserts in Ca., NM, Arizona, Mexico Lung infection - inhalation of spores cough, weigh loss, TB-like sx

Define the term: Virulence Factor; Why is it relevant that virulence factor genes are often carried on plasmids?

Virulence- the degree of pathogenicity of a microorganism. Pathogenicity- is the ability to cause disease by overcoming host defenses. Virulence Factors- are the molecules that assist the bacterium to colonize the host at the cellular level. Also as a way of colonizing they secrete a lot of stuff. Enzymes, and coagulase, that break down tissues that give the molecule the ability to get into the host. If one microorganism isn't pathogenic it can easily become pathogenic by getting plasmid from nearby microorganisms.

What is the cause or causes (etiologies) of: The Flu

Viruses infect the nose, throat, & lungs. Ex: Influenza viruses (A & B) Direct contact with nasal secretions, droplets, fomites

What is the cause or causes (etiologies) of: The common cold

Viruses that causes inflammation of the membranes that line the nose and throat. Ex: Rhinovirus, Adenovirus, Coronavirus Direct contact with nasal secretions, droplets, fomites

Lymphatic Filariasis

Wuchereria bancrofti & Brugia malayi • Elephantiasis + bacterial/fungal superinfections • 120 million infections worldwide (on the rise) • 40 million people debilitated • Tx: DEC, albendazole & ivermectin (in combination)

What is the cause or causes (etiologies) of: Aids

a chronic disease in which there is a severe loss of the body's cellular immunity, greatly lowering the resistance to infection and malignancy. AIDS is caused by the human immunodeficiency virus (HIV) and is the stage (Stage 3) of the infection when the immune system is badly damaged and the body becomes vulnerable to opportunistic infections. AIDS is technically defined as when the number of CD4 cells falls below 200 cells per cubic millimeter of blood (200 cells/mm3). (Normal CD4 counts are between 500 and 1,600 cells/mm3.)

What is the cause or causes (etiologies) of: Food poisoning

skin contact transmission, heat-stable enterotoxins (sAgs). Sudden onset (30min-8hrs) Nausea, diarrhea, vomiting, abdominal cramps. Self-limiting, complications are rare (1-3days)

Treponema pallidum: Syphilis

• 1400's • Spirochete bacteria • 4 stages • 1-chancre • 2-rash • 3-latent • 4-severe

Neissera gonorrhea

• 400,000 cases/yr • neonatal ophthalmia • Similar to chlamydia • cephalosporins

Soil & Arthopodborne Bacterial Diseases

• Anthrax • Bubonic Plague • Tetanus • Gas gangrene • Lyme disease • Rocky mountain spotted fever

Anthrax (not the band)

• Bacillus anthracus - Gram + spore former • Grazing animals are frequent carriers • Cutaneous (95%)-- Spores enter broken skin- 20% fatal- Painless necrotic ulcer • Inhalation - almost always fatal• GI forms - 25-60% fatal

Lyme Disease

• Borrelia burgdorferi - spirochete (1981) • 400k+ cases/yr • Age 5-14 highest risk, NE states • Rodents, deer & small animal reservoirs • Fever, neck & headache, fatigue • Arthritis, carditis, neurological involvement

STD's and other Contact Bacterial Diseases

• Chlamydia • Trachoma • Gonorrhea • Syphilis

Trachoma

• Chlamydia trachomatis • Endemic in many parts of Asia & Africa • Direct contact (eye secretions), mechanical vectors (flies) • 11 million cases/yr worldwide (6 million blind)

Food & Waterborne Bacterial Diseases

• Cholera • Salmonellosis & Shigellosis • Staph aureus, Clostridium & E. coli • Botulism • Typhoid fever • Listeria

Botulism

• Clostridium botulinum - G+ rod -- soil (spore former) • ~110 cases/yr (sporadic) • double vision, blurred vision, drooping eyelids, slurred speech, difficulty swallowing, dry mouth • 3-5% mortality - (respiratory failure) • Exotoxin-neurotoxin (BoNT)

Tetanus

• Clostridium tetani - Gram + rod (spore former) • ~30 cases/year in the US • Dust, feces, hospitals, soil • Deep puncture wounds, tooth extraction • Neurotoxin: Rigid paralysis • Vaccine available

Entamoeba histolytica

• Epidemiology: Worldwide distribution- Mexico, India, West and South Africa, South America • 10% of the world's population is infected • Most are asymptomatic (carriers) • 50-100,000 deaths per year • Vector: Flys carry cysts from human feces to human food or water or humans self-infect after touching fecally contaminated items, can be sexually transmitted • Reservoir: Humans are the only hosts • Pathologies: - Mild to severe intestinal discomfort - Dysentary (bloody diarrhea) - Can invade and destroy the liver - Treated with Metronidazole (flagyl)

Shigellosis & Salmonella

• Gram negative bacillus • Diarrhea, fever, vomiting & stomach cramps • Dysentery, tissue damage (Shigella) • Enterotoxins - shiga toxin • Fecal-oral transmission • 1-2 wks, usually self clearing • Water, vegies, swimming pools, poor hygiene • Salmonella: Poultry, eggs, reptiles, weed?

Listeria

• Listeria monocytogenes - Gram positive rod • fever, muscle aches, GI symptoms, miscarriage • 2500 cases/yr - 500 deaths • Pregnant/immunocompromised at increased risk • Crosses placenta • Food, water, animals, soil reservoirs

Chlamydia trachomatis

• Most common in US, ~75% unreported • Symptoms rare-65% no symptoms • Causes PID, infertility • 1 million new cases/yr • 2-3 million (prevelance)

Meningitis

• Neisseria meningitidis Gram neg. coccus (#1) • Haemophilus influenzae • Streptococcus pneumoniae Gram • High fever, headache, photophobia, stiff neck, nausea seizures, confusion • Droplet/contact transmission • 10-15% fatal, 10-20% brain damage, hearing loss, etc.

Aspergilliosis

• Ubiquitous in air (everyone is probably exposed) • Allergies common (ABPA) • Invasive Dx is rare • Immunocompromised • wheezing, coughing, fungus ball, bloody sputum • Voriconazole or other anti-fungals

Cholera

• Vibrio cholerae - Gram neg. vibrio • Liquid stool to shock in 4 to 12 hours • Death within 18 hrs • Enterotoxin- cholera toxin • Rapid dehydration, rapid pulse, dry skin, tiredness • Fecal-oral transmission • Shellfish may be reservoir- crabs • Tetracycline • Mesh filters • Chlorine

Bubonic Plague

• Yersinia pestis (Gram - bacillus) • Transmitted by fleas • Lymph swelling - "buboes" • Fever, lethargy, chills • "black death" • pneumonic plague • septicemic plague