2 Outline Who are we? Common infectious diseases How to prevent the spread of disease
3 A Few Questions… True or False: Hepatitis B is preventable with a vaccine, but there is no cureIf you have Hepatitis C, you will look very sickTricky questions:True and False: Hep B is preventable with a vaccine, and some people clear the virus on their own (they are cured), but there is no cure for people in whom the virus becomes chronic.False: If you have Hep C, you may not necessarily look sick. In fact, you may be asymptomatic.
4 A Few Questions True or False: Oral Herpes has a cure Chlamydia and gonorrhea are the most common sexually transmitted infections caused by bacteriaFalse: Oral herpes has no cure, but there are medications you can take to lessen the severity and length of outbreaksTrue: Chlamydia and gonorrhea are the most common sexually transmitted infections caused by bacteria
5 A Few Questions… True or False: Head lice cannot be spread by sharing a hairbrushTuberculosis only affects the lungsHIV and AIDS mean the same thingFalse: head lice can be spread by sharing a hairbrushFalse: Tuberculosis can affect many different organs, including the lungs, kidneys, bones, and brainFalse: HIV and AIDS are different…we’ll talk about that later.
6 Hepatitis Inflammation of the liver Bacteria Alcohol and toxins Your own immune systemVirusesMultiple different ones!Today – Focus on Hep B and CThe liver has many functions, such as:protein synthesismetabolism (processing) of key nutrients (fat, sugar, protein)hormone productionfiltering of harmful substances in bloodenergy storagevitamin and mineral storageImagine what can go wrong if the liver isn’t working well!Viral Hepatitis Screening:Explain inflammation (scraped knee or skin from as a kid analogy)Inflammation of the liver (inflammation is the body’s response to harmful things)caused by bacteria, toxins (drugs or alcohol), the body’s own immune systemmost often caused by a virus (a tiny infectious agent that can only replicate inside the cells of living organisms)five types of viral hepatitis: Hepatitis A, B, C, D, and Emost common are Hep A, B, and CToday we’ll talk about Hep B and C (Hep A rarely leads to permanent liver damage, fecal oral route and has a vaccine)
7 Hepatitis B Virus How do you get it? Blood Unprotected sexual contact Sharing needlesDuring birth if mother infectedBlood transfusion (rare)Some SymptomsNausea and vomitingJaundicePale feces/dark urinePain in upper right part of abdomenItching all over the bodyHow do you get it?Transmitted by the blood, including fluids contaminated with blood (unprotected sexual contact with infected person, blood transfusion, sharing needles, birth to infected mother)Not transmitted through food or water, sharing eating utensils, breastfeeding, hugging, kissing, holding hands, coughing, sneezing.HBV can survive outside the body for at least 7 days and still be capable of causing infection.What are the symptoms?FatigueNausea and vomitingLoss of appetiteJaundicePale feces/dark urinePain in upper right part of abdomenItching all over the body
8 Hepatitis B Virus Half of people show no symptoms Chronic Hep B – long-term infection5-10% of adults with Hep B develop thisCan lead toLiver scarringLiver cancerAcute infection ranges from asymptomatic to mild disease to very rarely fulminant hepatitis.Half of people infected with the virus will show no symptomsAcute Hep B: in most cases symptoms only last a few weeks to months, and then the virus is cleared (95%)Chronic Hep B: infection lasts over 6 months, and may never go awayOnly 5-10% of adults develop chronic infection, much higher in childrenCan cause scarring of the liver as well as liver cancer. Both can be fatal (15-25% of people with chronic infection will die of liver disease)Risky behaviour = Consider seeing a doctor about it?
9 Hepatitis B Virus Diagnosis: blood tests No cure for chronic Hep B Preventable with a vaccineTreatment: anti-retroviral drugsNo cure for chronic Hep B, but preventable with a vaccine (3 injections at 1mo, 2mo, and 6mo) – good for at least 20 years; also given after exposure to HBV to prevent infectionPersons who have already been infected will receive no benefit from the vaccinationTreatment (to reduce damage caused by the virus): anti-retroviral drugsAcute Hep B: no meds neededChronic Hep B: several antiviral drugs available; persons with chronic hep B infection require medical evaluation and regular monitoring to determine whether disease is progressing and to identify liver damage or hepatocellular carcinoma
10 Hepatitis C How do you get it? Blood Unprotected sex Sharing needles During birth if mother infectedBlood transfusions (rare)What are the symptoms?80% of people have no symptomsSymptoms may not show up for over yearsSimilar symptoms to Hep BHow do you get it?Blood borne and mother to child during birthSharing needles, blood transfusions, unprotected sexBefore 1992, when blood screening for HCV became available, blood transfusion was a leading means of HCV transmission.The most recent surveys of active IDUs indicate that approximately one third of young (aged 18–30 years) IDUs are HCV-infected. Older and former IDUs typically have a much higher prevalence (approximately 70%–90%) of HCV infectionWhat are the symptoms?80% of people no symptomsSymptoms may not show up for over yearsSimilar symptoms to Hepatitis BRisky behaviour = Consider seeing a doctor about it?
11 Hepatitis C Diagnosis: blood test 75% of adults with Hep C develop chronic infectionChronic Hep C can lead toLiver scarringLiver cancerThe cure rate with medication is ~50%At least 75% of people infected with Hep C develop Chronic Hep C (15-25% clear it without treatment)Most people with chronic HCV infection are asymptomatic.Prior infection with HCV does not protect against later infection (for the same reason why there is no vaccine)Chronic Hep C, like chronic Hep B, can lead to cirrhosis and liver cancerDiagnosis: anti-HCV (can be detected 4-10 weeks after infection) or HCV RNA (can be detected 2-3 weeks after infection)There’s no vaccine, but there are drugs to reduce the damage to the liver. Approximately 50% of chronically infected people respond to therapy.
12 Oral Herpes How do you get it? Touching infected saliva or skin Examples - lips, mouth, nostrils, ears, eyelids, genital area, anusSymptoms?Painful soresFever and muscle achesCommonly no symptomsNo cureWhat is it and what are the symptoms?an infection of the mouth and lips caused by the herpes simplex virus 1causes painful sores on the lips, gums, tongue, inside cheeks, the roof of mouth and sometimes on the face and neck (commonly called “cold sores”)can also cause fever and muscle achesup to 65% of the population will have been exposed to the virus by age 40commonly asymptomaticHow do you get it”touching infected saliva, skin or mucous membranes (lips, mouth, nostrils, ears, eyelids, genital area, anus)Progression: 3 Stagesprimary infection: virus enters skin through small breaks or cracks, replicates, and sores develop and last for 2 to 3 weeksLatency (dormant or quiet stage): virus moves to nerve tissue where it remains inactive, and there are no symptomsRecurrence: the virus may reactivate and cause symptoms again after certain events (such as stress, fatigue, sunshine) There is no cure but medication (antiviral drugs like Denavir or Valtrex) does exist to shorten outbreaks and lessen symptoms
13 Genital Herpes How do you get it? Skin-to-skin contact Sexual intercourse and oral sexSymptomsLesions and ulcersNo cureMedications to prevent and treat recurrencesHow do you get it?sexual intercourse and oral sexSkin-to-skin contactMany people are asymptomaticProgression and recurrence:Lesions typically last 2-3 weeks, then progress to ulcers,There is no cure but medications do exist to shorten outbreaks and lessen symptoms
14 Chlamydia and Gonorrhea How do you get it?Spread through vaginal, anal or oral sexSymptomsOften no symptomsDischarge, painful urination, feverTreatment is with antibioticsPreventionLimiting sexual partnerssafe sex practicesChlamydia and gonorrhea are most common sexually transmitted infections caused by bacteriaSpread is through vaginal, anal or oral sex, and from mother to baby during birthSymptoms:up to 50% of men and up to 75% of women do not experience symptomswomen: yellow or greenish cervical discharge that comes out of the vagina; painful urination; fever; abdominal painmen: painful or burning urination; yellow, white or green discharge from penis; tender testicals; feverDiagnosis:women: cervical secretions collected during pelvic examination are sent to the lab for testingmen: tiny cotton swab inserted into penis and sent to the lab for testingTreatment is with antibioticsLimiting sexual partners and safe sex practices are most effective prevention
15 Head Lice Live on the head and lay eggs How do you get it? Direct contactSharing hairbrushesHats, towels, clothing and beddingInsects that live on the scalp and lay eggs; may also be found in eyebrows and eyelashesAdult lice live ~30 daysEasily spreadDirect contact or sharing hairbrushes, hats, towels, clothing, bedding, etcCheck Family Members
16 Head Lice Symptoms Itchy scalp See nits in hair Live lice near scalp TreatmentShampoosProper cleaning of brushes, clothes and sheetsSymptoms (intense itching, but does not lead to serious medical problems)Itchy scalpSee nits in hair (whitish-grey, tan, yellow) that are size of sand. Often look similar to dandruffConfirm with identifying live lice near scalpTreatment (is recommended if even one egg is found)Insecticides (Found in special shampoo)No prescription neededNoninsecticideBreaks down exoskeleton of liceWash bedsheets in hot water
17 Scabies How do you get it? Direct contact such as sexual relations and handshakingTowels, clothing, beddingSymptomsSmall, raised bitesVery itchyWorse at nightBurrows under skin and lay eggsVery itchy lesions, worse at night (the itchy rash is an allergic response to the mites)Small papules with burrowsCommon in skin foldsSpreadpets and animals cannot spread human mitesHighly contagious with personal contact, infected bedding, sexual relations, handshakingCan be asymptomatic 2-4 weeks
18 Scabies Treatment Topical cream Wash bedding and clothing Diagnosis See burrowsMicroscopic visualization of mites, egg for accurate diagnosisTreatmentTopical Permethrin, a scabicide to kill mitesUsually only one applicationTreat all close contacts, even if not symptomaticWash bedsheets and clothing with hot waterPreventionDo not share clothes, towels, bedsheets
19 Syphilis How do you get it? Sexually transmitted Direct contact Symptoms6 weeks – ulcer6 months – rash, fever, aches6 years and longer – affects heart, brain, etc.TreatmentAntibioticsAbstain from sex during treatmentTreponema pallidum infectionSymptomsPrimary syphilis: Ulcer at area of infection, resolves on its own 3-6 weeksSecondary syphilis (weeks to months after 1°): Systemic rash, mucocutaneous lesions, adenopathyTertiary syphilis: Neurologic (asymptomatic, visual or hearing problems), cardiovascular (aortitis and aneurysm formation), gummatous (Granulomatous lesions in skeletal, skin, and mucocutaneous tissue)Latent syphilis: Asymptomatic positive treponemal antibody testCongenital syphilis: to fetus in utero
20 Tuberculosis How do I get it? Coughing Sneezing Talking Contributing FactorsImmunosuppressedDiabetesAlcoholInjection drug useSpread airborne from droplets from coughs, sneezes, talkingEnter the lungs and enter macrophages and spread to lymph nodesSeed distant organsKidneySkeletonJointsCentral nervous systemPleural and pericardial infectionContributing FactorsImmunosuppressed individualsDiabetesAlcohol useInjection drug useHigher among homeless, malnourished, and poorer populations
21 Tuberculosis Diagnosis Treatment Lungs infected most often Symptoms May have no symptomsCoughing and chest painFever and chillsNight sweats and weight lossDiagnosisSkin test, chest x-ray, labsTreatmentMultiple antibioticsAsymptomatic Primary InfectionBody protects itself and walls the bacteria in caseous granulomas that become fibrous and calcifiedSymptomatic Primary TBImmunocompromised (ex: AIDS)Secondary TBReactivation of infection in any organs that had primary infection due to a weakening of immune system (such as AIDS)
22 HIV Human immunodeficiency virus How do you get it? Sexual activity Blood transfusionsNeedle sharingMother to fetusHuman immunodeficiency virus (HIV)Retrovirus that is reverse transcribed into DNA and joins cell DNA (can hide from body defenses and be latent)SpreadSexual activity: present in seminal fluid and vaginal secretionsBlood transfusionsNeedle sharingMother to fetus (during pregnancy or at birth)Enter T-helper cells, which are cells that help protect the body from getting sickT-helper cells die and the body cannot protect itself from other illness
23 HIV Stages Acute viral illness Clinical latency (average 8 years) No symptomsLater symptomsFever and chillsNight sweats and weight lossHerpes infectionOral thrush – fungal infectionAIDSPneumoniaMeningitisBrain infectionsSevere mono infectionsAcute viral illnessusually 2-4 weeks post exposure – flu or mono like symptomsClinical latency (average 8 years)Constitutional Symptomsweight lossOral thrushHerpes zosterTBAIDS (CD4 Count<200)opportunistic infections and malignancies
24 HIV Diagnosis Blood testing Treatment Antiretroviral therapy with multiple medicationsPrevention! Avoid:Needle sharingUnprotected sexGet educated!DiagnosisAntibodies (initial screening)Viral RNAAntigens p24 found in blood with Western Blot TestAntibodies detected with Enzyme-linked immunosorbent assay (ELISA) testAIDSCD4 T-lymphocyte count less than 200TreatmentLower viral loadTreat opportunistic infectionsHighly Active Antiretrovial Therapy (HAART) – combination of at least 3 drugsPreventionAvoid needle sharing, unprotected sex, become educated!A course of antiretroviral treatment administered immediately after exposure, referred to aspost exposure prophylaxis, reduces the risk of infection If begun as quickly as possible.
25 A Few Questions… True or False: Hepatitis B is preventable with a vaccine, but there is no cureIf you have Hepatitis C, you will look very sickTricky questions:True and False: Hep B is preventable with a vaccine, and some people clear the virus on their own (they are cured), but there is no cure for people in whom the virus becomes chronic.False: If you have Hep C, you may not necessarily look sick. In fact, you may be asymptomatic.25
26 A Few Questions True or False: Oral Herpes has a cure Chlamydia and gonorrhea are the most common sexually transmitted infections caused by bacteriaFalse: Oral herpes has no cure, but there are medications you can take to lessen the severity and length of outbreaksTrue: Chlamydia and gonorrhea are the most common sexually transmitted infections caused by bacteria
27 A Few Questions… True or False: Head lice cannot be spread by sharing a hairbrushTuberculosis only affects the lungsHIV and AIDS mean the same thingFalse: head lice can be spread by sharing a hairbrushFalse: Tuberculosis can affect many different organs, including the lungs, kidneys, bones, and brainFalse: HIV and AIDS are different…we’ll talk about that later.27