Lec 13 HIV-HBV-HCV PDF

HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 III) Blood borne diseases Lecture 13: Blood borne diseases Intended Learning Outcomes (ILOs): Understand the size of the problem...

HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 III) Blood borne diseases Lecture 13: Blood borne diseases Intended Learning Outcomes (ILOs): Understand the size of the problem Describe the epidemiological determinates of HIV infection, HBV& HCV. Identify measures of prevention and control for HIV infection, HBV& HCV HIV/AIDS Blood borne diseases are threat to socioeconomic development, because it affects men and women in the most productive stage of their lives. It is a serious clinical condition with various manifestations, and characterized by underling cellular immunodeficiency Susceptibility: It is general, as no population is immune. - Age incidence: children and adolescents. - both sexes are affected but females are more affected during sexual intercourse. - High - risk: prostitute , Homosexuals, Drug addicts, STD patients. Etiology: Retrovirus. HIV: Human Immunodeficiency Virus Incubation period: It is unknown exactly. The mean of I.P is approximately 1 year in children and more than 5 years in adults. Mode of transmission: a. sexual intercourse (90%). b. Transmission through contaminated bloods or bloods products. Or contaminated skin piercing instruments (5%). c. From an infected woman to her child (20-45%) Clinical manifestations: 1- Acute (initial) infection: 83  HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 ▪ Following the infection of HIV and after a short period which is around 2 weeks 70% the infected persons may have non specific general manifestations such as fever, rashes, sore throat, depression ▪ lymphadenopathy (cervical, axillary and inguinal) ▪ muscular pain, fatigue, headache, maculopapular rash with truncal distribution, and cough.  These manifestations may remain for 1-2 weeks and disappear and the general condition returns too normal.  The person is highly infectious during this stage and capable of transmitting the virus efficiently. -Window period: patient is infectious because of high viral concentration in the blood but the antibodies are not produced in the blood (-ve test) 2- Latency period: Following the acute phase there is usually a period of latency, which lasts for a period varying from months to years. During this period the virus multiplies and infects more cells. 3-Persistent generalized lymphadenopathy (PGL): The patient with HIV infection has enlarged lymph nodes (greater than 1 cm in diameter) Involving two or more extra-inguinal sites 4- AIDS related complex (ARC): Occur due to damage of immune system: - Un explained diarrhea < 1 month - Loss of weight < 10% in all pts and it is progressive - Night sweating, headache, itching, amenorrhoea - Fever , malaise, fatigue, lethargy, anorexia, abdominal discomfort - generalized lymphadenopathy - enlarged spleen - Many present mucocutaneous lesions, these are important for early diagnosis of AIDS 5- AIDS: End stage of HIV infections, MOST sever stage. The same clinical pictures of ARC. Many opportunistic infections as T.B and Cancer specific to immuno- deficiency state occurs. Also known as Slim disease because of presence of chronic diarrhea and weight loss. WHO criteria for clinical diagnosis of HIV/ AIDS 84  HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 A person is considered to have AIDS if at least 2 of the following major signs are present in combination with at least 1 of the minor signs: 2 Major signs + 1Minor sign = - Weight loss ≥ 10% of body - cough >1 month AIDS weight - generalized pruritic dermatitis - chronic diarrhea > 1 month - Zoster - fever > 1 month - oropharyngeal candidiasis - disseminated herpes simplex - generalized lymphadenopathy Laboratory diagnosis: Lab. diagnosis services for HIV infections include: a. Serologic testing for antibodies to HIV (ELISA) b. Confirmatory test (Western Blot Techniques). c. Diagnosis of the degree of immunosuppressant (CD4 Cell count) d. Diagnosis of opportunistic infections. Prevention General measures: 1. Health education: About the nature of the disease, modes of transmission and dangers of promiscuous sexual relations. Special educational massages should be directed to the high- risk groups who are more prone to infection. 2. Prevention of sexual transmission: Efforts should be made to benefit from the strong religious believed in promoting healthy lifestyles and refereeing from unhealthy ones, including promiscuous relations. Prevention of perinatal transmission: Infected women should advise against pregnancy, both for their health and for fear of transmitting infection to the baby. 3. Prevention of blood-borne transmission: - Avoiding unnecessary blood transfusion. - Strictly use protective equipment in contact with blood or non-intact - tissues. - Screening of blood and blood donors. - Proper precautions while producing blood products. - Changing socio-cultural behaviors such as tattooing, drug abuse etc. 4. Case management: Case detection, notification and inform them about the nature of the disease and how they can protect others. 5. Vaccine development: There are numerous vaccine under development Treatment: 85  HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 3 main fields are present: ▪ Drugs that suppress HIV infection. ▪ Drugs that improve host immune functions so reduce the development Of HIV associated infections and malignancies. ▪ drugs that prevent or treat AIDS-related infections including opportunistic infections and malignancies. Effectiveness of antiretroviral drugs Take more than one antiretroviral drug at a time. Is known as Combination Therapy. Highly Active Antiretroviral Therapy (HAART) Is used to describe a combination of three or more anti-HIV drugs. Taking two or more antiretrovirals at the same time TO reduces the rate at which resistance develops. Post-exposure prophylaxis for HIV (PEP): is the use of ARV (antiretrovirals) drugs within 72 hours of exposure to HIV to prevent infection. PEP includes counselling, first aid care, HIV testing, and administration of a 28-day course of ARV drugs with follow-up care. WHO recommends PEP use for both occupational and non-occupational exposures and for adults and children. Hepatitis B It causes 80% of hepatocellular carcinoma. In Egypt, its prevalence 2-4%. Etiology: HBV (hepadena virus), DNA virus. Reservoir: case, carrier (convalescent, incubatory and healthy carrier). About 6-10% of infected adults develop carrier and 90% of perinatal infections develop carrier. Communicability: during HBsAg positive. Modes of transmission: 1. Percutaneous and per-mucosal exposure to infective body fluids: Blood transfusion. Organs transplants, Sharing needles, Hemodialysis, Needle stick, Tattooing, toothbrushes. 2. Sexual transmission. 3. vertical transmission High risk for hepatitis B: 1. Live with a person who has chronic hepatitis B. 86  HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 2. Have sex with an infected person 3. Infants born to infected mothers. 4. Travel to countries with moderate to high rates of hepatitis B. 5. Inject drugs or share needles, syringes, or other drug equipment. 6. Exposed to blood on the job. 7. Hemodialysis patients. 8. Have a sexually transmitted disease or homosexual. Incubation period: 6 weeks to 6 months Symptoms of acute hepatitis B: Fever, Fatigue, Loss of appetite, Nausea, Vomiting, Abdominal pain, Dark urine, Clay colored stool Joint pain Jaundice Symptoms usually last a few weeks, but some people can be ill for as long as 6months. Symptoms of chronic hepatitis B Most individuals are asymptomatic for as long as 20 or 30 years. Symptoms similar to acute hepatitis B A serious disease that can result in long-term health problems, including liver damage, liver failure, liver cancer, or even death Diagnosis: Clinical picture. Laboratory (Hepatitis markers): Hepatitis B Surface Antigen (HBsAg): appear during incubation period and persist for 3 month. A positive test means that person has an acute or chronic hepatitis B virus infection and can pass the virus to others, A negative test means: person does not have the hepatitis B virus in his or her blood. Hepatitis B Surface Antibody (anti-HBs): A person is protected or immune from getting the hepatitis B virus for one of two reasons: he or she was successfully vaccinated against hepatitis B OR he or she recovered from an acute infection (and can’t get hepatitis B again). HBc Core: active replication of virus, Accurate more than HBeAg, Used mainly for monitoring response to therapy 87  HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 Total Hepatitis B Core Antibody (anti-HBc): IgM indicate acute infection, IgG indicate currently or was infected in past. Hepatitis B “e” Antigen (HBeAg): indicate high infectivity and detect the effectiveness of treatment. Hepatitis B e Antibody (HBeAb or anti-HBe): indicate reduced infectivity and reduced viral replication. Hepatitis B Viral DNA: high infectivity. Prevention 1. Primary Prevention: 1-General Measures: - blood and its products; strict sanitary measures - Sterilization and use disposable syringe - Preventive measure of tattooing, acupuncture, and ear piercing, - Avoidance of sexual promiscuity and drug addiction. - Health education of transmission and preventive measures 2- Specific Measures: ▪ Inactivated, Plasma-derived vaccine; it is inactivated virus developed from plasma of persistent HBV carriers. ▪ Recombinant DNA vaccine it is prepared on yeast by genetic engineering. It is very expensive. HBV vaccine had been started compulsory to be given in Egypt to infant at 0, 2, 4, and 6 months and is given routinely to medical and paramedical personnel and cases of repeated blood transfusion in 4 doses 0.5 ml each, IM. After receiving all 4 doses, hepatitis B vaccine provides greater than 90% protection to infants, children, and adults N.B It is the first vaccine ageist cancer. Post exposure prophylaxis for: 1- Infants born to HBsAg positive mothers. 2 - Individuals who had exposed to HBV. First 12 h. of birth or exposure: receive dose of HBIG & HB vaccine. 2-3 doses of vaccine given over the next 1–15 months. 4- Secondary Prevention: 1. Cases: Notification, isolation, and treatment, symptomatic 88  HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 Concurrent disinfection of excreta, articles and fomites. Strict sanitary measures 2.Contacts: surveillance for 6weeks Seroprophylaxis by immunoglobulin Health education Hepatitis C According to WHO, 2017: Globally, an estimated 71 million people have chronic hepatitis C infection. 55–85% of infected persons will develop chronic HCV infection. In Egypt: according to WHO (2015) it affects about 20% of Egyptian.. Hepatitis C usually disease of adult, infectious liver disease that ranges in severity from a mild illness lasting a few weeks to a serious lifelong illness. Etiology: HCV, RNA flavivirus. Reservoir: cases, carrier. (incubatory Transmission / Exposure 1. Mode of transmission: mainly by blood:Contact with contaminated blood or less commonly contaminated body fluids (e,g, sharing infected needles, razors or tooth brushes). 2. Being born to a mother who has hepatitis C (vertical transmission). 3. Having sexual contact with infected person (less common). Incubation period: 6 - 10 weeks (acute cases), 2 - 6 months (chronic cases). Clinical picture: 1-Acute HCV infection: insidious onset, with vague abdominal discomfort, anorexia, nausea, vomiting, fever and fatigue progressing to jaundice in about 25% of patients. The fate of acute disease: Fulminant liver failure: rare. Resolve without squeal: 15-25%. Become chronic : in 75-85%. Cirrhosis: 5-20% Death from cirrhosis and/or liver cancer: 5% 2- Chronic HCV infection: No symptoms in most cases (60%-80%). 89  HEALTH AND ILLNESS IN THE COMMUNITY BLOCK HIC-211 A complex clinico-pathological syndrome with varying stages of necro- inflammatory and sclerosing liver damage. 60-70%, persistent or fluctuating ALT elevations indicating developing of active liver disease. Diagnosis: Clinically Laboratory by: RT-PCR: Hepatitis C viremia may be detected by RT-PCR within days acute hepatitis C and in 50-70% of patients with chronic hepatitis C. Therefore, anti HCV IgM cannot be used a reliable marker of acute HCV infection Prevention: There is no vaccine or immune globulin (IG) products A. General measures: Implementation and maintenance of infection-control practices Adequate sterilization of reusable material such as surgical instruments. Screening and testing of blood, plasma & plasma-derived products, organs, tissues, and semen. Risk-reduction counseling and services. B. Secondary prevention Professional and public education Identification, counseling, and testing of persons at risk Medical management of infected persons. Surveillance and research to monitor disease trends and the effectiveness of prevention activities and to develop improved prevention methods. 90