Epi Cheat Sheet PDF

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1.  History:

Epidemiology = study of distribution, occurrence and case of disease Impact of Diseases = kill more people than wars, threat to survival, shape development of society.

 Biological weapons – Mongols  Being fall of roman empire  Justinian Plague killed 50,000,000  Miasmas vs Germ theory – believed disease spread via foul air.  Jenner (1796) – small pox vaccination from cowpox (milkmaid)  Pasteur – pasteurization, Rabies vaccine  Lister (1867) – surgical antisepsis  Koch (1882) – postulates, Discovered TB. John Snow – father of epidemiology  1849 Cholera outbreak via water/ food contamination (sewage)  1854 – Cholera in Soho, London – 500 deaths in 10 days. John found increase outbreaks around area of certain water pump. 2. Transmission of Infection & Diagnosis 4. Emerging Diseases History 1.

430BCE Plague of Athens 1st pandemic, haemorrhagic fever Typhoid – faecal – oral transmission 25% troops & 70% Athens population killed 2. 165-180AD Antonine Plague Helped bring about fall of Roman Empire 5,000 Killed by smallpox/ day Diarrhoea, inflammation of throat 3. 541-542AD Justinian Plague 40% Constantinople died 60% European population 5,000-10,000 dead/ day Yersinia Pestis from Egypt 4. 1347-1351 Black Death ~60% European Population Bacteria carried by rats + fleas 80% died in a week From Africa 5. 1918-1920 Spanish Flu 1/3 of worlds population, 50-100 million deaths H1N1 virus Cytokine storm ^ incident in 14-35yo Drivers of Emerging diseases 1. Demographics 2. Industry 3. Land Use 4. Global Transport 5. Resistance 6. Climate change 7. Public Health Measures Diseases  SARS (sever, acute respiratory syndrome) Corona virus, identified in China, recognised in Vietnam 2003 Cough, breathing difficulty, low platelets, fevers 9.6% mortality, 66% fatality rate. Transmission= palm civets consumption – airborne, 4-5day incubation. Rapid spread via air passengers  EBOLA (^2014) Highly contagious haemorrhagic disease, fevers, bleeding, Bat contraction Human – human by fluid transmission ^ in developing countries  MERS- corona virus Chest pain, fever, cough, diarrhoea. T: analgesic , fluid replacement, ventilation  ZIKA virus – joint pain, rash, fever, red eyes. Spread by aedes aegypti, south America. T: no vaccine/ specific treatment, relief of symptoms, Aspirin, anti-inflammatory drugs. Preventing Diseases: Isolation, Data sharing, Economic/ political Support, Education, Disease Notification, Trained Personnel.

3. Vaccination & Immunisation History  17th Century India & China  1796 Jenner & Milkmaids – power injected under skin  Vaccination from Vacca – cow Vaccine Timeline / Affect – significantly lowers cases of disease  Smallpox – Jenner (eradicated, polio next?) , Rabies – Pasteur, Typhoid, Cholera, Plague Vaccine –ves: some don’t provide long lasting immunity eg. Whooping cough ^ cases 2016 Ideal Vaccine:  Doesn’t cause disease  Provides Protection  1 dose enough  No Side effects  No cold chain Vaccine Types 1. Live: can replicate in host cannot cause disease due to being attenuated. +ve= cellular / humoral immune resistance. Low dose is ok, Long lasting protection. –ve = Not given to immune-compromised. May revert Transmission possible. Cold Chain. 2. Inactive: Intact antigens, nuclear remnants destroyed by heat / chemicals / radiation. Eg.Rabies, Pertussis, Typoid, Poli (salk). +ves = Don’t cause disease, Stable, No cold chain. –ves= lower immunity, doesn’t last long. 3. Subunit: present antigen to immune system without viral particle. +ves= low reactions, simple to make, freeze – easy transport. –ves = lower immunity, boosters needed.  Toxoids – inactive toxins, toxins are modified  inactive toxin = toxoid. Eg Pertussis (whooping cough)  Polysaccharides common in bacterial membrane. Eg. Meningitis/ influenza  Recombinant Vaccines- DNA from virus into plasmid  human eg. Hep B vaccine  Genetic Vaccines – DNA/ RNA – new cannot yet be licensed. DNA into gold particle  host. Components of Vaccines 1. Active, innate or subunit 2. Adjuvant materials: help boost bodies immune response to antigens by increasing antibody production.. Eg. Aluminium: ^ T-cell activation, ^ Time of immunity. 3. Inactivating agents: inactivate virus eg. Formaldehyde detoxifies the toxin in tetanus 4. Preventing contamination agents (preservatives / antibiotics): prevents fungal/ bacterial contamination. Eg. Preservatives, Antibiotics. Immunity Intramuscular, intradermal, subcutaneous.  Innate= Non-specific, no memory, physical barriers  Adaptive= Specfic, learned immunity, ^ immune reponse to 2nd exposure. Natural: Passive- antibody transfer, active- vaccine. Artificial: passive- maternal, active – infection. Humoral =Antibody mediated. Cell= CD4 &CD8 mediated. Vaccines do not cause Autism- guy is in jail/ incorrect study.

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5. Food- borne Diseases Cost - $1.25 million, 120 deaths, 5.4million cases in Aus/yr. Mostly decreasing, except salmonella. Incubation may be 20min 6wks! Recent Outbreaks:  Salmonella – mars chocolate  Gastro- raw milk  Salmonella – coles pre-washed lettus  Listeria – rock melons  Hep A virus – berries from china Cause of Contamination  Cooking temp / storage time  Environment / person  Adequate growth conditions: salt, pH, O2, temp. Cold (inhibits growth), warm (sterilizes) 40% of foodborne diseases=  Eggs, tuna, cheese, oysters, potatoes, ice-cream, sprouts, salad, berries, tomatoes. Food Poisoning = Food Intoxication = injection of pre-formed (cyto, neuro & entero) toxins secreted by bacteria. Toxins- Treatment = antitoxin 1. Exotoxin – mostly GN Diphtheria Breathing difficulties Tetanus Spores enter through wounds causing muscle spasm, Neurotoxin Cholera Binds to intestinal cell wall Adenylyl cyclase  water out of cells 2.

Endotoxin – part of bacterial cell wall, released upon lysis or when bacteria is killed by antibiotics. , Mostly GP Staphylococcus aureus Vomiting, diarrhoea. Human  food. TSS. Bacillus cereus Spore forming, acid/heat stable. Enteric syndrome. Starchy food: fried rice. Botulism - chlostridium Muscle weakness, dummy- honey  Floppy baby syndrome. Can dishes Food Infection = ingestion of microbe, which causes disease Longer incubation time ^ diarrhoea, vomiting, gastroenteritis Organisms produce toxins whilst living in gut, usually self limiting, Clostridium Spore forming, anaerobic GPR, in GIT of animals, soil & dust. Found in cooked meat dishes where it is Perfringens kep warm. Cooking fails to kill endospores & encourages germination, time/ warmth allows growth. (can dishes) Enterotoxin made in gut upon sporulation. 12- 18hr incubation, diarrhoea, self limiting. Salmonella Enteric fever, no gastro enteritis facultative GNR, human’s only reservoir. Faecal – oral. Intrinsically typhi(eggs, raw human – human. Survives in macrophages, multi organ systemic disease. milk chicken, meat) Campylobacter Curved, microaerophilic, thermophilic motile GNR; GIT of birds, reptiles, amphibians, pets). Involves raw (raw milk, milk, raw or undercooked meats (especially poultry), (eggs); acquisition from pets; contaminated water. poultry. Food acts as vehicle (no organism growth in food); low infectious dose; adhesion and invasion of enterocytes. 16 - 48hr incubation; profuse (bloody) diarrhoea, often severe abdominal pain leading to hospital presentation; self-limiting. Vibrio (curved, facultative GNR; sea water and shellfish). raw and semi-cooked fish and shellfish Parahaemolytic organisms grow during inappropriate storage of seafood; adhere and are enteroinvasive. 4 - 30hr us (seafood) incubation; Ds (bloody), fever, nausea, abdominal pain; self-limiting (rehydration, antibiotics). Diagnosis by enrichment (alkaline peptone water) and culture (TCBS) produce an enterotoxin active in vitro against Vero cells (thus VTEC), and cause haemorrhagic enteritis E. coli (thus enterohaemorrhagic E. coli – EHEC). (facultative GNR; ruminant GIT) . contaminated meats which (water pre-cut are undercooked or under- fermented (mettwurst). bacteria adhere and produce verotoxin in gut (toxin fruit&vege, meat, raw milk) similar to Shigella- shiga toxin) 1 - 6 day incubation, followed by watery diarrhoea progressing to bloody; risk of haemolytic uraemic syndrome (coagulopathy and haemolysis, renal failure and CNS involvement) diagnosis: culture. (sorbitol non-fermenter; unlike other E. coli strains) E. coli strains involved: mostly O157:H7 and O111 (O refers to lipopolysaccharide serotype; H to flagella serotype) Gram+ve rod, motile; ubiquitous in dust, soil, food-processing plants, ra foods and GIT of humans and Listeria animals. Long incubation period (3-6 weeks common). Infection is generally invasive. Symptoms include Monocytosis (cheese, pre-cut vomiting, diarrhoea, fever, headaches- can cause septicaemia, meningitis, spontaneous abortion. High fruit&vege) risk food- unpasteurised dairy- soft cheeses, raw seafood, processed meats. USA estimates- 1600 cases and 260 deaths annually. diagnosis by culture and organism identification Viral HepatitisA(HAV). Rotavirus Norovirus, Sapovirus, Adenovirus, Astrovirus. faecal-oral transmission via Gastroenteritis contaminated foods (which are not heated before serving); and water (and person-to-person). Gastroenteritis (Rotavirus, Norovirus, Adeno & Astro); hepatitis from HAV. Common infections in children. Hep A (pre-cut fruit & vege)

6. Water- borne diseases – water practical Transmission (bacteria, viruses + protozoan) Cost 7. Air-borne Diseases & Blood – borne diseases 8. - Contact 2.3 million die/ yr Respiration – breathe 6-10L/min 1/6 no access to safet drinking water - Hand Cough:contact innate immune response to irritation of trachea / bronchi 82 million8disability days Sneeze: irritation of nasal cavity, 4m range, 20K particles released ~10 shed/day, organisms can also survive on surfaces - -Diarrhoea =cells 4% of all deaths Speaking: release of particles. Potable Water -No e.coli faecal – oral Saliva: 1L produced / day. Transmits: EBV, HSV, meningococcus. (= faecal contamination) Aerosol transmission: most effective when people are in close range. Small ~10um particles can stay Hospital acquired infections: 7-10% of patients, 7,000 - -Filtration membrane in air for ~ 20min Sedemenation deaths/yr, $950 million cost/yr No backflow, pressurised Upper Respiratory Tract infections Hand HOCl-, washing = prevention. Most common is s.aureus (1,400 - -Disinfectant O3, UV Otitis ear: externa (auditory canal), media (middle ear) or interna (inner ear). Infected by: Durability Swimmer’s cases in reported in hospitals/yr) s.aureus, candida, opportunists. Months inpseudomonas, soil (salmonella) Sinustitis- -Paranasal sinus mucosasa congestions. Blocked Infected by: strep. Pneumonia, Types: pyogenic (pus), for toxigenic (toxin), enterotoxigenic Intestine viruses in sewage treatment months sinuses. haemophilus influenza, selfcysts limiting. Giardia & cryptosporidium & nematode eggs – highly resistant to chlorination (enterotoxin produced).live long time DiphtheriGPR, club shaped, Bull neck, toxin made diffuses into underlying Spores, eggs, cystsCorynebacterium – hardy and can diptheriae. a Travellers tissue  death epithelia (holes)bacteria:  necrotic ulceration  exudate of fibrin ‘pseudomembrane Blood Borne 80% of cause diarrhoea, e.coli, salmonella, shigella, vibrio,campylobacter pharynx.’Heart & neural problems. ^ fatality rate, rare, toxoidgiardia, vaccine.cryptosporidium Diarrhoea-overTransmission: 20% caused by blood-blood, virus/ protozoan: rota virus, norovirus, tattooing, needles, razors, bites, 3-5 days. Diarrhoea / vomiting  dehydration  death Lower Respiratory Tract Infections wounds, Dysentry Bloody/transfusion. pussy diarrhoea, fever vomiting. Shigella or Entamoeba Lystolytica. Whooping Bortella pertussis, very Inhibit cilia and kill epithelial cells by producing toxins. May Incubation 12-24hrs. Kills 700,000/yr HBV > HCV >infectious. HIV (infection risk depends on disease) Cough & death in young. Vaccinedeaths/ available. Cholera cause pneumonia 1.3 – 4 million cases /yr. 21-143K year. Mild/ no symptoms. Vomiting/ Pneumoni - Inflammation of lung. Cells / mucous block airways & harden alveoli. be viral, bacterial or Needle –stick injury ~30%, HBV 3%, HIV 0.3% diarrhoea with mucous/ epithelia cells in poo. Toxin binds toCan epithelial cells of lumen a fungal: s.pneumoniae 20-60% cases. Adenylate Usually lobar, pharyngeal colonizer. 1’ changes Atypical Pneumonia altering electrolyte balance. cyclase  ATP  cAMP  ion - (non- pneumococcal). H.influenzae (5-15%), s.aureus, klebsiella pneumonia, legionella –potting balance -> water flows out. Treatment= fluid and electrolyte replacement. air conditioning. Viral:2-3 influenza / measeles. S/S: chest pain,whilst breathing Hep mix, A contaminated dsDNA. Most common liver disease. survive 7 days Vaccination= 2-3 doses, lasts yrs. Haiti – helper Can spread bacteria helping difficulty, after fever,earthquake. cough, confusion. Complications: Septicemia, meningitis, empyema. T: virusantibiotivs, outside body. Blood – blood, vertical, saliva, semen. vaccines (pneumococcus, measles, Hib.in water. ^ in S/S: Salmonella GNR. Diarrhoea, vomiting forpertussis 4-7 days.influenza, Faecal contamination Influenza RNA enveloped virus type A,B C eg. H1N1 swine flu pandemic. A: bird6mths = (42*C) chronic, 0.1-0.5% Campylobacter GNR, thermophilic 10% CO2, 5%O2. blood), incubation around winter. JeuriHep crompromised 2-7days. From food, chicken, milk, water. C ssRNA. needle-stick – blood, vertically. S/S: 3, TB Mycobacterium TB.Transmission: Fevers, cough, weight-loss. 1, Get into lungs, 2, ingested by macrophage, E.coli Specific stereotypes: 0156: H7, Haemolytic Uraemic Syndrome. toGNR. Lymph nodes – T-cell activation. ~10 0111,026. bacilli = infectious dose. Complicated treatment: virusMigrate25-35% symptomatic, 60-75% fail to clear virus…develop Bloody diarrhoea. Eating uncooked meat / swimming/ drinking CD4 contaminated DOTS. 90% latent (non-infectious) & will never develop active disease. T cells are liver failure (30% asymptomatic). 233K chronic inof TB sewage. essential. HIV/AIDS patients are stay susceptible to TB! Mantoux test = skin test, injection Giardiasis components Motile, protozoan parasite. Faecaloral contaminated water. Infectious dose = 10monitor inflammatory reaction. Aus.–Diagnosis EIA, response. PCR. Testing for delayed hypersensitivity 20 cyts. Large bump = +veGiardia adhere to enterocytes via sucking disc. Incubation 9-15 days may HIV infections ssRNA carrying reverse Transmission: become chronic. Non- respiratory – caught via aerosols but don’ttranscriptase. affect lungs. Cryptosporidiosi Parasite. Ingestion of incubation. unpasteruised milk/ contaminated water. 14 days. Measles Enveloped RNA virus, 1-2 wk Flu-like symptoms, cough skin rash. Complications sexual, transfusion, vertical, 12% unaware. Affects T CD4 – s pneumonia, CNS inflammation, vaccines, only reported cases = imported cases eg. Student cells. Virus incoorportates ssRNA into genome of infected Norovirus bringing Hardy virons, 1-3day incubation, faecaloral. Deletion: PCR EIA, virus survives it in from oversease. freezing/ 60*C, Cl-. cell, killing it.10ppn, Decreased immune function, succeptible to Mumps Enveloped ssRNA virus, neck swelling Rotavirus German Infants, nursery epidemics, faecal – oral, survives on objects. Asymptomaticcongential, in Rubella measles, enveloped RNA virus. Contagious, mild rash, 50% asymptomatic, AIDS.. adults, discovered in Aus. 90% infant abnormalities. Entero virusChicken Affect GIT, polio, coxsackie, echovirus, HepEIAA. Faecal – oral. shingles AIDS CD4 cells...