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Hepatitis B and C Virus

Hepatitis B and C Virus. What is Hepatitis……..? Medical condition defined by the inflammation of the liver. The condition can progress to fibrosis (scarring) and cirrhosis. Hepatitis may occur with limited or no symptoms, but often leads to jaundice, anorexia (poor appetite) and malaise.

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Hepatitis B and C Virus

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  1. Hepatitis B and C Virus

  2. What is Hepatitis……..? • Medical condition defined by the inflammation of the liver. The condition can progress to fibrosis (scarring) and cirrhosis. • Hepatitis may occur with limited or no symptoms, but often leads to jaundice, anorexia (poor appetite) and malaise. • Hepatitis is acute when it lasts less than six months and chronic when it persists longer.

  3. Types of Hepatitis A B C D E Source of feces blood/ blood/ blood/ feces virus blood-derived blood-derived blood-derived body fluids body fluids body fluids Route of fecal-oral percutaneous percutaneous percutaneous fecal-oral transmission permucosal permucosal permucosal Chronic no yes yes yes no infection No vaccine blood donor Passive immunization Active immunization Prevention ensure safe Prevention of HBV infections drinking • Blood donor • screening screening; water Active immunization risk behavior modification

  4. Hepatitis B Virus Characteristics of the virus • DNA virus from Hepadna virusfamily

  5. Hepatitis B Virus Modes of Transmission • Sexual- Sex workers and homosexuals are particular at risk. • Parenteral– Intra venous drug abuse (IVDA), Health Workers are at increased risk. • Perinatal- Mothers who are HBeAg positive are much more likely to transmit to their offspring than those who are not. Perinatal transmission is the main means of transmission in high prevalence populations.

  6. Concentration of Hepatitis B Virus in Various Body Fluids Low/Not High Moderate Detectable blood semen urine serum vaginal fluid feces wound exudates saliva sweat tears breastmilk

  7. 1- Clinical Features of acute hepatitis B: The incubation period: Between 45 and 120 days, with an average of 60 to 90 days. Common clinical features are : Chronic Persistent Hepatitis – asymptomatic. Chronic Active Hepatitis - symptomatic exacerbations of hepatitis. Cirrhosis of Liver. Hepatocellular Carcinoma.

  8. Markers for Diagnosis Various serological tests are used for the diagnosis of acute and chronic hepatitis B infection. • HBsAg- used as a general marker of infection. • HBsAb- used to document of immunity to HBV infection. • anti-HBcIgM- marker of acute infection. • anti-HBcIgG– indicates past or chronic infection. • HBeAg- indicates active replication of virus. • HBV-DNA – Also indicates active replication of virus. Used mainly for monitoring response to therapy.

  9. Laboratory Diagnosis (Techniques) • Several serological Test are available for detection of above mention markers as: • ELISA • Immunochromatography • RIA • Also DNA of the virus can be detected using PCR Technique.

  10. HBsAg Rapid Test • The HBsAg rapid test device: Is a chromatographic immunoassay for the qualitative detection of HBsAgin whole blood, serum or plasma. • The membrane is pre-coated with anti-HBsAgantibodies on the test line region of the device. Specimen + Anti-HBsAg antibodies conjugated particles Generates a colored line which indicates a positive result.

  11. Method: • Allow the test device, specimen, buffer and/ or control to equilibrate to room Temperature prior to testing. • For serum or plasma specimen:Hold the dropper vertically, transfer 3 drops of serum or plasma to the specimen well (S) of test device and then start the timer. • For Whole Blood specimen: Hold the dropper vertically, transfer 3 drops of venipuncture or 75 ul of fingerstick whole blood to the specimen well (S) of test device, then add 1 drop of buffer and start the timer. • Wait for the colored line(s) to appear. The result should be read at 15 minutes.

  12. Interpretation of Results • Positive: Two distinct colored lines appear. One line should be in the control region(C) and another in the test region(T). • Negative: one colored line appears in the control region(C). • Invalid: Control line fails to appear.

  13. HEPATITIS C VIRUS (HCV) Characteristics of the virus Single -stranded RNA virus of family: Flaviviridae

  14. Mode of Transmission of HCV • Transfusion or transplant from infected donor. • Intravenous drug abuse (IVDA). • Hemodialysis (years on treatment). • Accidental injuries with needles/sharps. • Sexual/household exposure to HCV-positive contact. • Multiple sex partners. • Birth to HCV-infected mother.

  15. Hepatitis C - Clinical Features • Incubation period: • Average (6-7 wks) - Range (2-26 wks). • Chronic Hepatitis C Infection: • The spectrum of chronic hepatitis C infection is essentially the same as chronic hepatitis B infection. • All the manifestations of chronic hepatitis B infection may be seen, although with a lower frequency i.e. chronic persistent hepatitis, chronic active hepatitis, cirrhosis, and hepatocellular carcinoma.

  16. Laboratory Diagnosis • HCV antibody:Generally used to diagnose hepatitis C infection. Not useful in the acute phase as it takes at least 4 weeks after infection before antibody appears. • HCV-RNA: Various techniques are available e.g. PCRmay be used to diagnose HCV infection in the acute phase. However, its main use is in monitoring the response to antiviral therapy. • HCV-antigen:ELISA is used for detection. It is used in the same capacity as HCV-RNA tests but is much easier to carry out.

  17. HCV Rapid Test Device • HCV Rapid Test Device (Serum/plasma): Is a qualitative, membrane based immunoassay for the detection of antibody to HCV in serum or plasma. The serum or plasma The recombinant HCV antigens coated particles. Colored line. reacts with

  18. Method • Allow the test device, specimen, buffer and/ or control to equilibrate to room Temperature prior to testing. • Using Disposable Specimen Dropper : Hold the dropper vertically, draw the specimen up to the fill line and transfer to the specimen well (S) of test device, then add 2 drops of buffer and start the timer. • Wait for the colored line(s) to appear. The result should be read at 10 minutes

  19. Interpretation of Results • Positive: Two distinct colored lines appear. One line should be in the control region(C) and another in the test region(T). • Negative: one colored line appears in the control region(C). • Invalid: Control line fails to appear.

  20. Human Immunodeficiency Virus(HIV)

  21. Introduction • It causes Acquired Immunodeficiency Syndrome (AIDS). • Discovered during 1983-1984. • HIV-2 discovered in 1986, antigenically distinct virus and endemic in West Africa.

  22. Characteristics of the virus • Icosahedral (20 sided), enveloped virus of the lentivirus subfamily of retroviruses. • Retroviruses transcribe RNA to DNA. • Two viral strands of RNA found in core surrounded by protein outer coat. • Outer envelope contains a lipid matrix within which specific viral glycoproteins are imbedded. • These knob-like structures responsible for binding to target cell.

  23. HIV-1 and HIV-2: • HIV-1 and HIV-2 are:• Transmitted through the same routes.• Associated with similar opportunistic infections. • HIV-1: is more common worldwide. • HIV-2 : • Is found in West Africa, Mozambique, and Angola. • Is less easily transmitted. • HIV-2 is less pathogenic.

  24. :Mode of transmission • Sexual transmission, presence of sexually transmitted disease (STD) increases likelihood of transmission. • Exposure to infected blood or blood products. • Use of contaminated clotting factors by hemophiliacs. • Sharing contaminated needles (IV drug users). • Transplantation of infected tissues or organs. • Mother to fetus (perinatal transmission) is variable and dependent on viral load and mother’s CD-4 count.

  25. Primary HIV Syndrome • Mononucleosis-like, cold or flu-like symptoms may occur 6 to 12 weeks after infection. • Lymphadenopathy. • Fever. • Rash. • Headache. • Fatigue. • Diarrhea. • sore throat. • neurologic manifestations. • Some times no symptoms may be present

  26. Symptoms are relatively nonspecific. • HIV antibody test often negative but becomes positive within 3 to 6 months, this process is known as seroconversion. • Large amount of HIV in the peripheral blood. • Primary HIV can be diagnosed using viral load titer assay or other tests. • Primary HIV syndrome resolves itself and HIV infected person remains asymptomatic for a prolonged period of time, often years.

  27. Clinical Latency Period: • HIV continues to reproduce, CD4 count gradually declines from its normal value of 500-1200. • Once CD4 count drops below 500, HIV infected person at risk for opportunistic infections. • The following diseases are predictive of the progression to AIDS: • persistent herpes-zoster infection (shingles) • oral candidiasis (thrush) • oral hairy leukoplakia • Kaposi’s sarcoma (KS)

  28. Oral candidiasis (thrush) Herpes-zoster infection • Oral hairy leukoplakia Kaposi’s sarcoma

  29. Spectrum of HIV Tests 1- HIV diagnosis (Antibody/Antigen testing): • Enzyme Immunoassays (EIAs) • Rapid tests • Western blot (WB) 2- Early diagnosis in infants: • P24 3- Monitoring of ART: • CD4 • Viral Load

  30. HIV Rapid Tests: • Qualitative assay to detect HIV antibodies. • Most detect HIV 1 and HIV 2. • As reliable as EIAs . • Body Fluids Used for HIV Rapid Testing: • Serum. • Plasma. • Whole blood.

  31. Immunochromatography Rapid Test:Method The test procedure and interpretation of results is same as in HCV & HBV Rapid tests.

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