Presentation on theme: "Principles of Asepsis Chapter 19 Medical Assisting"— Presentation transcript:
1Principles of Asepsis Chapter 19 Medical Assisting PowerPoint® presentation to accompany:Medical AssistingThird EditionBooth, Whicker, Wyman, Pugh, Thompson
2Learning Outcomes19.1 Explain the historical background of infectious disease prevention.19.2 Identify the types of microorganisms that cause disease.19.3 List some infectious diseases, and identify their signs and symptoms.19.4 Discuss the importance of preventing antibiotic resistance in a health-care setting.19.5 Describe ways you can help prevent antibiotic resistance in health-care settings.
3Learning Outcomes (cont.) 19.6 Explain the disease process.19.7 Explain how the body’s defenses protect against infection.19.8 Describe the cycle of infection.19.9 Identify and describe the various methods of disease transmission.19.10 Explain how you can help break the cycle of infection.
4IntroductionOur bodies are amazing structures that defend us against infections undernormal circumstancesYou will learn about:Disease-causing microorganismsHow the body fights diseaseWays infections occurAntibiotic-resistant organismsImportance of patient education on the proper use of antibiotics
5History of Infectious Disease Prevention Throughout history people have attempted to discoverCauses of infectionHow to prevent infectionsHow to treat infections
6History of Infectious Disease Prevention (cont.) ScientistContributionEdward Jenner (1749–1823)Developed first effective vaccineUsed cowpox to vaccinate against small poxIgnaz Semmelweis (1818–1865) and Oliver Wendell Holmes (1809–1894)Promoted handwashing as a means of reducing the spread of Puerperal fever to women in childbirth
7History of Infectious Disease Prevention (cont.) ScientistContributionLouis Pasteur (1822–1895)Helped develop the germ theory of infectious disease stating that disease is caused by microorganismsJoseph Lister (1827–1912)Helped develop germ theoryIntroduced aseptic techniques through the use of antiseptics on wounds, surgical sites, and surgical instruments
8History of Infectious Disease Prevention (cont.) ScientistContributionRobert Koch (1843–1910)Developed a set of proofs, known as Koch’s Postulates, claiming that microbes cause diseaseSir Alexander Fleming (1881–1955)Discovered penicillin
9History of Infectious Disease Prevention (cont.) Remarkable advances in the past centuryThreat of infection still presentNew infectious diseasesAIDSEbolaResistant diseasesMRSAVRSAMultidrug-resistant TB
10Right! Apply Your Knowledge Why is the threat of infection still present even though great advances have been made in controlling infections over the past century?ANSWER: The threat of infection is still present because of new diseases and diseases that have become resistant to treatments.Right!
11Microorganisms and Disease Microorganisms live all around usPathogensMicroorganisms capable of causing diseaseEvade host defensesPeople avoid infections most of the timeMany microorganisms are beneficial or harmlessNormal defenses resist infectionConditions are not favorable for pathogens to grow and be transmitted
12Microorganisms and Disease (cont.) ClassificationCharacteristicsExampleDiseasePrions *Infectious particle made of proteinNo nucleic acidReproduction unknownPr PCJDBSEMad cow disease* Experts disagree as to whether prions are directly responsible for disease or merely aid an unknown agent in causing disease.
13Microorganisms and Disease (cont.) ClassificationCharacteristicsExampleDiseaseVirusesDNA or RNA surrounded by protein coatReproduced in living cellsVery smallVaricella-zoster virusChickenpoxBacteriaSingle-celledReproduce quicklyMostly asexual reproductionVibrio choleraeCholera
14Microorganisms and Disease (cont.) ClassificationCharacteristicsExampleDiseaseProtozoansSingle-celledReproduction mostly asexualEntamoeba histolyticaAmebic dysenteryFungiMulticellularReproduction is sexual and asexualCandida albicansCandidiasisHelminthsMulticellular parasiticContain specialized organsSexual reproductionEnterobius vermicularisPinworms
15Correct! Apply Your Knowledge In many cases, we avoid contracting infections when exposed to microorganisms. What are the reasons for this?ANSWER: This is because:many microorganism are beneficial or harmlesswe have normal defenses to resist infectionconditions are not favorable for the pathogen to grow and be transmitted.Correct!
16Infectious DiseasesKnowing signs and symptoms of common infectious diseases can help protect against exposure
17Infectious Diseases (cont.) Chickenpox (Varicella)Contagious viral infectionIncubation period of 7 to 21 daysItchy rash fluid-filled blistersSlight fever, headache, general malaiseSpread by direct, indirect, droplet, or airborne transmissionIsolate until all blisters have scabbed over1996 – live vaccine approved
18Infectious Diseases (cont.) Common coldViral infections of upper respiratory tractNo isolation neededCommonsense precautions to prevent spreadUse tissues when coughing or sneezingWash hands frequentlyUse disposable dishware, if possibleIncubation – 2 to 3 days
19Infectious Diseases (cont.) CroupMost often caused by a virusCharacterized by a harsh, barking cough, difficulty breathing, hoarseness, and low-grade feverMost common in infants and young childrenSymptoms lessened by humidification of air, rest, and clear fluidsCommonsense precautions to prevent spread
20Infectious Diseases (cont.) DiphtheriaBacterial infection of nose, throat, and larynxSymptoms: pain, fever, respiratory obstructionIncubation – 2 to 5 daysIsolation requiredAntibiotic therapy (fatal if untreated)Immunization available
21Infectious Diseases (cont.) Epstein-Barr VirusCommon human virus95% of adults have had virus35 – 50% of teens develop mononucleosisSymptoms – fever, sore throat, swollen lymph nodesVirus remains dormant for lifeOccasionally reactivates as tumors
22Infectious Diseases (cont.) Haemophilus Influenzae Type BBacterial infections in infants and young childrenSpread – direct, indirect, and droplet transmissionIncubation – 3 daysUpper respiratory symptoms, fever, drowsiness, body aches, diminished appetiteMonitor closely – bacterial meningitis
23Infectious Diseases (cont.) HepatitisViral infection of liverSpread through blood or fecal-oral routeHIV/AIDSHuman immunodeficiency virusAcquired immune deficiency syndrome
24Infectious Diseases (cont.) Influenza (Flu)Symptoms – fever, chills, headaches, body aches, upper respiratory congestionIsolation and commonsense precautionsVaccinesLive, attenuated virus – nasal sprayInactivated virus – IM injectionAnnual vaccinationPeople at risk for complicationsPeople older than 50 years oldPeople in close contact with persons at risk for complications
25Infectious Diseases (cont.) Measles (Rubeola)Infectious viral diseaseSpread by droplets or direct transmissionInitial symptom of fever develops 8 to 13 days after exposure, followed by a characteristic itchy rash 14 days after exposureIsolation for 7 days after rash appearsKeep children under 3 years old away from anyone with the diseaseReportable to state or county health dept.
26Infectious Diseases (cont.) MeningitisInflammation and infection of protective coverings of brain and spinal cord and the fluids around themViral – milder formClears in 1 to 2 weeks without treatmentAseptic meningitis
27Infectious Diseases (cont.) MeningitisBacterial – serious, life-threatening, requiring immediate treatmentVaccination available for people in high-risk groupsSymptoms – red, blotchy rash, confusion, delirium, light sensitivity, headache, fever and chills, nausea and vomiting, sleepiness, stiff neckMay spread through exchange of respiratory and throat secretionsReportable to state or county health dept.
28Infectious Diseases (cont.) MumpsViral infectionPrimarily affects salivary glandsIncubation – 2 to 3 weeksPain related to inflammation of parotid gland and feverIsolate until glandular swelling stopsReportable to state or county health dept.
29Infectious Diseases (cont.) Pertussis (Whooping Cough)Highly contagious bacterial infection of respiratory tractSymptoms – fever, sneezing, runny nose, quick short coughs, characteristic “whoop” during inhaled breath following coughing fitIsolate for 3 weeks following onset of spasmodic coughsReportable to state or county health dept.
30Infectious Diseases (cont.) RoseolaRose-colored rash possibly caused by human herpes virusInfants and young childrenIncubation 5 to 15 daysSymptoms – sudden, high fever; sore throat; swollen lymph nodes; rashRubella (German Measles)Highly contagious viral diseaseDirect or droplet transmissionIncubation 16 to 18 daysSymptoms – fever and itchy rashVaccination availableReportable
31Infectious Diseases (cont.) Streptococcal pharyngitis (strep throat)Bacterial infection of throatSore throat, swelling of pharyngeal mucosa, fever, headache, nausea, abdominal painTreat with antibioticsScarlet feverBacteria becomes systemicCharacteristic “strawberry rash”Incubation 7 to 10 daysIsolate 7 days
32Infectious Diseases (cont.) Streptococcal pharyngitis (cont.)Rheumatic feverOccurs after apparent recovery from strep throatAutoimmune disorder – antibodies to streptococci cross-react with heart tissuesSymptoms – carditis, ECG changes, joint pain and inflammation, feverAcute post-streptococcal glomerulonephritisInflammation of glomerulus of the kidney resulting in inadequate filtering of the bloodSymptoms – swelling of hands and feet, decreased urine output, hypertension, protein in urine
33Infectious Diseases (cont.) TetanusAcute infectious bacterial disease following a contaminated puncture woundIncubation – 3 to 21 daysLate symptoms – lockjaw, paralysisNo isolation needed, but reportable
35Infectious Diseases (cont.) Tuberculosis (cont.)Increasing resistance to TBEarly diagnosis, prompt treatmentCompliance with treatment regimenPreventing TBVaccination – BCG (not used in the U.S.)Causes false-positive with TB skin test
36Infectious Diseases (cont.) Tuberculosis (cont.)Treating TBMantoux TB testPositive test = Induration – skin turns red and becomes raised and hardPositive result from immunization or exposure to TB bacteriaTreatment based on area affected and type of TB involvedPatients must complete entire course of treatment – 12 to 18 months on medicationIsolation
37Excellent! Apply Your Knowledge How can the spread of many infectious diseases can be limited or prevented?ANSWER: The spread of many infectious diseases can be limited or prevented by using common sense precautions:Using tissues when coughing or sneezingWashing hands frequentlyUsing disposable dishwareExcellent!
38Drug-Resistant Microorganisms MRSA – methicillin/oxacillin-resistant S. aureusVRE – vancomycin-resistant enterococciVISA – vancomycin-intermediate S. aureusVRSA – vancomycin-resistant S. aureusESBLS – extended-spectrum beta-lactamasesPRSP – penicillin-resistant Streptococcus pneumoniae
39Drug-Resistant Microorganisms (cont.) MRSA and VREMost common in non-hospital health-care facilitiesCommunity-associated MRSAIncreasing in incidencePRSPCommon in patients seeking care in physicians’ offices and clinics (pediatrics)
40Drug-Resistant Microorganisms (cont.) Risk factors for development of infections by drug-resistant organismsAdvanced ageInvasive proceduresPrior use of antibioticsRepeated contact with health-care systemSeverity of illnessUnderlying diseases of conditions
41Drug-Resistant Microorganisms (cont.) Preventing antibiotic resistanceFour strategies to reduce incidence of antibiotic-resistant microorganismsPrevent infectionDiagnose and treat infection appropriatelyUse antibiotics carefullyPrevent transmission of infections
42Apply Your KnowledgeWhat strategies reduce the incidence of antibiotic-resistant microorganisms?ANSWER: Strategies to reduce the incidence of antibiotic-resistant microorganisms include:Prevent infectionsDiagnose and treat infections appropriatelyUse antibiotics carefullyPrevent transmissionGood Job!
43Disease Process Begins with microorganisms finding host Grows with specific requirementsProper temperaturepHMoisture levelVirulence – microorganism’s disease-producing powerDamage is caused by:Depleting nutrientsReproducing themselvesMaking body cells the target of body’s own defensesProducing toxins
44Disease Process (cont.) Once exposed to a pathogen, the body goes through 4 stages of illness:Incubation – begins at first exposure; ends when first symptom appearsProdromal – begins at first onset of symptoms; generally shortInvasion – numbers of organisms are greatest; symptoms are most pronouncedConvalescent – patient regains normal health status
45Apply Your Knowledge SUPER! What are the four stages of illness? ANSWER: The four stages of illness are:Incubation – begins at first exposure; ends when first symptom appearsProdromal – begins at first onset of symptoms; generally shortInvasion – numbers of organisms are greatest; symptoms are most pronouncedConvalescent – patient regains normal health statusSUPER!
46The Body’s Defenses First lines of defense Immunity – condition of being resistant to pathogens and the disease they causeFirst lines of defenseSkinSweat glandsMucous membranesCiliaLacrimal glandsSalivaHydrochloric acidLysozyme
47The Body’s Defenses (cont.) Resident normal flora – microorganisms found in the bodyProvide a barrier against pathogensNormally live in balanceBecome pathogenic when host’s defenses are compromisedOpportunistic infectionsInfections occurring when a host’s resistance is low
48The Body’s Defenses (cont.) Immune system includes nonspecific defensesMechanisms to protect against pathogens in generalIncludesNonspecific defensesHumoral defensesCell-mediated defenses
49The Body’s Defenses: Nonspecific InflammationSignsRednessLocalized heatSwellingPainPurposeSummon immunologic agents to siteBegin tissue repairDestroy invading microorganismsStepsInitial constriction, then dilation of blood vessels, causing redness and heatFluid leakage from local vessels swellingScar tissue formationChronic inflammation damages tissues and causes permanent loss of function
50The Body’s Defenses: Nonspecific (cont.) PhagocytosisWhite blood cells (phagocytes) engulf and digest pathogensThree typesNeutrophils – found in pusMonocytes – formed in bone marrow and becomeMacrophages when they migrate to specific tissuesFound in lymph nodes, liver, spleen, lungs, bone marrow, and connective tissueDeliver antigens (foreign substances) to lymphocytes
51The Body’s Defenses: Humoral Immunity Lymphocytes – B cells and T cellsT cells activate B cells to produce antibodies to neutralize an antigenMemory B cells respond quickly to produce antibodies in later invasionsSpecific antibodies are produced in response to specific antigensAntibodies attract phagocytes, which destroy antigens
52The Body’s Defenses: Humoral Immunity (cont.) Types of immunityActive – body produces own antibodiesNatural activeArtificial activePassive – antibodies that are produced outside body enter the bodyNatural passiveArtificial passiveComplementProteins activated by antibodiesHelps white blood cells destroy pathogens
53The Body’s Defenses: Cell-Mediated Immunity T cells attack invading pathogen directlyHelper T cellsActivateKiller T cellsBind with antigen and kill itSuppressor T cellsSlow down or stop attack after antigen is destroyedMemory T cellsRespond quickly to another attack by same antigen
54Impressive! Apply Your Knowledge What is the difference between active and passive immunity?ANSWER: Active immunity is long-term immunity in which the body produces its own antibodies.Passive immunity results when antibodies produced outside the body enter the body.Both can be natural or artificial.Impressive!
55Click for Cycle of Infection A reservoir host – animal, insect, or human body capable of sustaining pathogen growthCarrier – unaware of presence of pathogenSubclinical case – unnoticeable infectionEndogenous infection – normally harmless microorganisms become pathogenicExogenous infection – pathogen introduced into the bodyClick for Cycle of Infection
56Cycle of Infection (cont.) Means of exit – how the pathogen leaves the hostNose, mouth, eyes, or earsFeces or urineSemen, vaginal fluid, or other reproductive dischargeBlood or blood productsClick for Cycle of Infection
57Cycle of Infection (cont.) Means of transportation – how a pathogen spreads to a hostAirborneBlood-borneDuring pregnancy or birthFoodborneVector-borneLiving organism that carries microorganisms to another personTouchingDirectIndirect through fomitesInanimate reservoir of pathogensDrinking glass, door knob, etc.Click for Cycle of Infection
58Cycle of Infection (cont.) Means of entranceEnter through any cavity lined with mucous membraneMouth, nose, vagina, rectumEars, eyes, intestinal tract, urinary tract, reproductive tract, breaks in the skinClick for Cycle of Infection
59Cycle of Infection (cont.) Susceptible hostIndividual with little or no immunity to infection by a pathogenHost factors influencing susceptibilityAgeGenetic predispositionNutritional statusOther disease processesStress levelsHygiene habitsGeneral healthPathogen factorsNumber and concentrationVirulencePoint of entryClick for Cycle of Infection
61Cycle of Infection (cont.) Environmental factorsDense populationsAnimalsUnpasteurized milkInsectsEconomic and political factorsAvailability of transportationPopulation growth ratesSexual behavior
62Nice Job! Apply Your Knowledge What are fomites? ANSWER: Fomites are inanimate objects such as clothing, water, and food that serve as a means of transportation for microorganisms.Nice Job!
63Breaking the CycleAsepsis – condition in which pathogens are absent or controlledMaintain strict housekeeping standardsAdhere to government guidelines to protect against diseaseEducate patients in hygiene, health promotion, and disease prevention
64Medical Assistant In Summary As knowledge about causes of infection have increased, principles and practices of asepsis have developed.Medical AssistantMust learn how pathogens cause disease, how disease is transmitted, and how to prevent the spread of infection.Use this knowledge to educate patients about remaining healthy and decreasing the risk of contracting disease.
65End of ChapterEnd of Chapter 19In today's world, new infections and diseases can spread across the country and even across the world in a matter of days, or even hours, making early detection critical.~ John LinderU.S. Representative, Georgia