Successfully reported this slideshow.
We use your LinkedIn profile and activity data to personalize ads and to show you more relevant ads. You can change your ad preferences anytime.

AIDS/HIV Testing Methodology (www.ubio.in)

8,163 views

Published on

HIV testing methodologies: an Introduction

for more presentations and tutorials visit
http://www.ubio.in

Published in: Technology, Health & Medicine
  • DOWNLOAD FULL BOOKS, INTO AVAILABLE FORMAT ......................................................................................................................... ......................................................................................................................... ,DOWNLOAD FULL. PDF EBOOK here { https://tinyurl.com/yyxo9sk7 } ......................................................................................................................... ,DOWNLOAD FULL. EPUB Ebook here { https://tinyurl.com/yyxo9sk7 } ......................................................................................................................... ,DOWNLOAD FULL. doc Ebook here { https://tinyurl.com/yyxo9sk7 } ......................................................................................................................... ,DOWNLOAD FULL. PDF EBOOK here { https://tinyurl.com/yyxo9sk7 } ......................................................................................................................... ,DOWNLOAD FULL. EPUB Ebook here { https://tinyurl.com/yyxo9sk7 } ......................................................................................................................... ,DOWNLOAD FULL. doc Ebook here { https://tinyurl.com/yyxo9sk7 } ......................................................................................................................... ......................................................................................................................... ......................................................................................................................... .............. Browse by Genre Available eBooks ......................................................................................................................... Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult,
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here
  • DOWNLOAD FULL BOOKS, INTO AVAILABLE FORMAT ......................................................................................................................... ......................................................................................................................... 1.DOWNLOAD FULL. PDF EBOOK here { https://tinyurl.com/y3nhqquc } ......................................................................................................................... 1.DOWNLOAD FULL. EPUB Ebook here { https://tinyurl.com/y3nhqquc } ......................................................................................................................... 1.DOWNLOAD FULL. doc Ebook here { https://tinyurl.com/y3nhqquc } ......................................................................................................................... 1.DOWNLOAD FULL. PDF EBOOK here { https://tinyurl.com/y3nhqquc } ......................................................................................................................... 1.DOWNLOAD FULL. EPUB Ebook here { https://tinyurl.com/y3nhqquc } ......................................................................................................................... 1.DOWNLOAD FULL. doc Ebook here { https://tinyurl.com/y3nhqquc } ......................................................................................................................... ......................................................................................................................... ......................................................................................................................... .............. Browse by Genre Available eBooks ......................................................................................................................... Art, Biography, Business, Chick Lit, Children's, Christian, Classics, Comics, Contemporary, Cookbooks, Crime, Ebooks, Fantasy, Fiction, Graphic Novels, Historical Fiction, History, Horror, Humor And Comedy, Manga, Memoir, Music, Mystery, Non Fiction, Paranormal, Philosophy, Poetry, Psychology, Religion, Romance, Science, Science Fiction, Self Help, Suspense, Spirituality, Sports, Thriller, Travel, Young Adult,
       Reply 
    Are you sure you want to  Yes  No
    Your message goes here

AIDS/HIV Testing Methodology (www.ubio.in)

  1. 1. <ul><li>HIV testing </li></ul><ul><li>Methods and Procedures </li></ul>
  2. 2. <ul><li>diagnosis of infection </li></ul><ul><ul><li>acute, recent, established or late stage disease </li></ul></ul><ul><li>prognostic markers </li></ul><ul><li>monitoring of ARV therapies </li></ul><ul><ul><li>immunological and virological markers </li></ul></ul><ul><ul><li>toxicities </li></ul></ul><ul><li>diagnosis of opportunistic infections </li></ul><ul><li>drug resistance testing </li></ul><ul><li>Laboratory Tests </li></ul>
  3. 3. <ul><li>Typical Primary HIV-1 Infection </li></ul>symptoms HIV-1 p24 antigen 0 1 2 3 4 5 6 / 2 4 6 8 10 weeks years HIV antibodies Time following infection HIV viral load HIV proviral DNA symptoms ‘ window’ period 1° infection
  4. 4. <ul><li>Types of HIV Assays </li></ul>DIAGNOSIS Virus Detection & Quantification Antibody Antigen Detection RNA modified Ag Viral Culture, phenotyping CD4+ ARV Resistance – genotyping ARV Sensitivity EIA Simple, rapid tests Immunoblots Incident assays MANAGEMENT DNA (RNA)
  5. 5. <ul><li>HIV Test Spectrum </li></ul>DNA PCR RNA PCR p24 Ag 3rd gen ELISA 1st gen ELISA Detuned ELISA 1wk 2wk 3wk 2mo 6mo 1yr 2yr 3yr +8yr early recent / established advanced
  6. 6. <ul><li>HIV p24 antigen– serology </li></ul><ul><ul><li>In isolation or Ab/Ag Combo test </li></ul></ul><ul><ul><li>Diagnosis of primary infection viraemia </li></ul></ul><ul><li>Virus culture/isolation </li></ul><ul><li>Nucleic acid detection (NAT) </li></ul><ul><ul><li>Clinical uses Proviral DNA vs. plasma RNA(viral load) resolution of inconclusive serology/neonatal </li></ul></ul><ul><ul><li>subtyping </li></ul></ul><ul><ul><li>drug resistance monitoring </li></ul></ul><ul><li>Direct Virus Detection </li></ul>
  7. 7. <ul><li>Principle of Immunoassays </li></ul>SOLID PHASE ANTIGEN SAMPLE ANTIBODY ANTI-HUMAN IMMUNOGLOBULIN WITH DETECTOR
  8. 8. <ul><li>EIAs including </li></ul><ul><ul><li>rapid, simple assays </li></ul></ul><ul><ul><li>particle agglutination </li></ul></ul><ul><ul><li>dot/blot </li></ul></ul><ul><ul><li>Western blot </li></ul></ul><ul><ul><li>Antigen and Antibody/Antigen (Ab/Ag) </li></ul></ul><ul><ul><li>Incidence assays </li></ul></ul><ul><li>Direct Virus Detection </li></ul><ul><li>Available Assays </li></ul>
  9. 9. <ul><li>Dot/Blot Assays </li></ul>
  10. 10. <ul><li>Particle Agglutination Assays </li></ul>
  11. 11. <ul><li>technically more difficult </li></ul><ul><li>visual interpretation </li></ul><ul><li>lack standardisation </li></ul><ul><ul><li>Performance </li></ul></ul><ul><ul><li>Interpretation </li></ul></ul><ul><li>‘ Gold Standard’ for confirmation </li></ul><ul><li>Western Blot </li></ul>
  12. 12. <ul><li>Difficulties in interpretation </li></ul><ul><li>Limitations - ‘window period’ </li></ul><ul><li>antibodies appear within 3-4 weeks </li></ul><ul><ul><li>Direct detection for early detection </li></ul></ul><ul><ul><li>HIV p24 antigen </li></ul></ul><ul><ul><li>DNA/RNA (NAT) </li></ul></ul><ul><li>Combo test = earlier detection </li></ul><ul><li>Primary infection + therapy = delayed antibody response </li></ul><ul><li>Incident populations – ‘at risk’ </li></ul><ul><li>Antibody Testing: Limitations </li></ul>
  13. 13. <ul><li>Detection of Ag & Ab in a single test </li></ul><ul><li>utility in primary infection – pre-seroconversion ‘window period’ </li></ul><ul><li>Useful for blood banks </li></ul><ul><li>Automated platforms available </li></ul><ul><li>Ag/Ab Combo Tests </li></ul>Ag & Ab
  14. 14. <ul><li>Chance of false reactivity </li></ul><ul><li>Might need confirmation tests </li></ul><ul><li>Replacement by other assays (especially in the USA) </li></ul><ul><li>More expensive than Antibody assays </li></ul><ul><li>Ag/Ab Assays: Limitations </li></ul>
  15. 15. <ul><li>Detect HIV-1 & HIV-2 </li></ul><ul><li>Cannot differentiate between HIV types </li></ul><ul><li>Procedural control using anti human IgG </li></ul><ul><li>Can test using whole blood, serum or plasma </li></ul><ul><li>Widely available </li></ul><ul><li>No additional reagents required </li></ul><ul><li>Storage at room temperature </li></ul><ul><li>15 minutes to get result </li></ul><ul><li>Simple Assays: HIV Determine </li></ul>
  16. 16. <ul><li>Detects HIV-1 and HIV-2 </li></ul><ul><li>Will differentiate between types 1 and 2 </li></ul><ul><li>Procedural control using anti-human IgG </li></ul><ul><li>Serum/plasma only </li></ul><ul><li>Need additional reagents (included in kit) </li></ul><ul><li>Requires refrigerated storage </li></ul><ul><li>‘ Immunoconcentration’ principle </li></ul><ul><li>15 minutes to result </li></ul><ul><li>BioRad HIV-1/2 Multispot </li></ul>
  17. 17. <ul><li>Strategy I : Test all samples with one EIA </li></ul><ul><li>Strategy II: Strategy I with all reactives retested in a more specific test with different principle and/or antigen. </li></ul><ul><li>Strategy III: Strategy II with reactives tested in a third test differing from the first two tests. </li></ul><ul><li>Transfusion Safety </li></ul><ul><ul><li>Strategy I </li></ul></ul><ul><li>Surveillance </li></ul><ul><ul><li>>10% Strategy I, < 10% Strategy II </li></ul></ul><ul><li>Diagnosis </li></ul><ul><ul><li>>10% Strategy II, < 10% Strategy III </li></ul></ul><ul><li>WHO Test Strategies </li></ul>
  18. 18. <ul><li>Use strategy for confirmation </li></ul><ul><ul><li>Use combination of affordable and simple assays </li></ul></ul><ul><ul><li>Use tests with different principles </li></ul></ul><ul><ul><li>Use different antigen preparations </li></ul></ul><ul><li>Use two or three types of ELISAs or rapid tests </li></ul><ul><li>diagnosis confirmed by second sample </li></ul><ul><li>Use direct detection of virus (PCR) for final confirmation </li></ul><ul><li>Important: Always use a QC sample </li></ul><ul><li>WHO Test Guidelines </li></ul>
  19. 19. <ul><li>www.ubio.in </li></ul>

×