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Rapid HIV Tests

Rapid HIV Tests. Norman Moore, Ph.D. Director of Medical Affairs.

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Rapid HIV Tests

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  1. Rapid HIV Tests Norman Moore, Ph.D. Director of Medical Affairs

  2. A majority of the information in this lecture was taken from the CDC Lecture by Bernard Branson, M.D.Associate Director for Laboratory DiagnosticsDivisions of HIV/AIDS PreventionNational Center for HIV, STD, and TB PreventionCenters for Disease Control and PreventionThe views of Dr. Branson are not necessarily the official views of the CDC.

  3. Awareness of HIV Status among Persons with HIV, United States Number HIV infected 1,039,000 – 1,185,000 Number unaware of their HIV infection 252,000 - 312,000 (24%-27%) Estimated new infections annually 40,000 Glynn M, Rhodes P. 2005 HIV Prevention Conference

  4. Late HIV Testing is CommonSupplement to HIV/AIDS Surveillance, 2000-2003 • Among 4,127 persons with AIDS*, 45% were first diagnosed HIV-positive within 12 months of AIDS diagnosis (“late testers”) • Late testers, compared to those tested early (>5 yrs before AIDS diagnosis) were more likely to be: • Younger (18-29 yrs) • Heterosexual • Less educated • African American or Hispanic *16 states MMWR June 27, 2003

  5. Reasons for testing: late versus early testers Supplement to HIV/AIDS Surveillance, 2000-2003

  6. Previous Recommendations

  7. Previous CDC RecommendationsAdults and Adolescents • Routinely recommend HIV screening in acute-care hospital settings with HIV prevalence >1% • Targeted testing based on risk assessment in clinical settings with lower HIV prevalence

  8. HIV Testing Practices in EDs • Survey of 154 ED providers • Average: 13 STD patients per week • Only 10% always recommend HIV test • Reasons for not testing for HIV: • 51% concerned about follow up • 45% not a “certified” counselor • 19% too time-consuming • 27% HIV testing not available -Fincher-Mergi et al, 2002: AIDS Pat Care STDs

  9. Previous CDC RecommendationsPregnant Women • Routine, voluntary HIV testing as a part of prenatal care, as early as possible, for all pregnant women • Simplified pretest counseling • Flexible consent process

  10. Revised Recommendations for HIV Testing of Adults, Adolescents, and Pregnant Women in Health-Care SettingsMMWR 2006;55 (No. RR-14):1-17Published September 22, 2006 http://www.cdc.gov/mmwr/pdf/rr/rr5514.pdf

  11. Revised RecommendationsAdults and Adolescents - I • Routine, voluntary HIV screening for all persons 13-64 in health care settings, not based on risk • All patients with TB, or seeking treatment for STDs, should be screened for HIV • Repeat HIV screening of persons with known risk at least annually

  12. Revised RecommendationsAdults and Adolescents - II • When acute retroviral infection is a possibility, use an RNA test in conjunction with an HIV antibody test • Settings with low or unknown prevalence: • Initiate screening • If yield from screening is less than 1 per 1000, continued screening is not warranted

  13. Revised RecommendationsAdults and Adolescents - III • Opt-out HIV screening with the opportunity to ask questions and the option to decline testing • Separate signed informed consent should not be required • Prevention counseling in conjunction with HIV screening in health care settings should not be required

  14. Revised RecommendationsAdults and Adolescents - IV • Screening is voluntary • Inform patients orally, or in writing, that HIV testing will be performed unless they decline. • Arrange access to care, prevention, and support services for patients with positive HIV test results

  15. Rationale for Revising CDC Recommendations • Many HIV-infected persons access health care but are not tested for HIV until symptomatic • Effective treatment available • Awareness of HIV infection leads to substantial reductions in high-risk sexual behavior • Inconclusive evidence about prevention benefits from typical counseling for persons who test negative • Great deal of experience with HIV testing, including rapid tests

  16. Veterans Health System • December 2008 – The Veterans’ Mental Health and Other Care Improvements Act of 2009 repealed the limitation on HIV screening. • August 2009 Written consent is no longer required for HIV testing in the VHA • Patients only need to provide verbal informed consent prior to HIV testing • VHA National HIV Program Directive • HIV testing should be a part of routine medical care and pro

  17. Criteria that Justify Routine Screening • Serious health disorder that can be detected before symptoms develop • Treatment is more beneficial when begun before symptoms develop • Reliable, inexpensive, acceptable screening test • Costs of screening are reasonable in relation to anticipated benefits • Treatment must be accessible Principles and Practice of Screening for Disease -WHO Public Health Paper, 1968

  18. Knowledge of HIV Infection and Behavior After people become aware they are HIV-positive, the prevalence of high-risk sexual behavior is reduced substantially. Reduction in Unprotected Anal orVaginal Intercourse with HIV-neg partners: HIV-pos Aware vs. HIV-pos Unaware 68% Meta-analysis of high-risk sexual behavior in persons aware and unaware they are infected with HIV in the U.S. Marks G, et al. JAIDS. 2005;39:446

  19. Effect of Counseling in Conjunction with HIV Testing • Meta-analysis of 27 studies of HIV-CT: • HIV-positive participants reduced unprotected intercourse and increased condom use. • HIV-negative participants did not modify their behavior more than untested participants. - Weinhardt et al, 1999: Am J Public Health

  20. Opt-Out Screening Prenatal HIV testing for pregnant women: • RCT of 4 counseling models with opt-in consent: • 35% accepted testing • Some women felt accepting an HIV test indicated high risk behavior • Testing offered as routine, opportunity to decline • 88% accepted testing • Significantly less anxious about testing Simpson W, et al, BMJ June,1999

  21. Cost Effectiveness • Expanded screening for HIV in the U.S. – an analysis of cost effectiveness. Paltiel AD, et al. NEJM 2005;352:586. “In all but the lowest-risk populations, routine, voluntary screening for HIV once every 3 to 5 years is justified on both clinical and cost-effectiveness grounds. One-time screening in the general population may also be cost-effective.”

  22. Cost Effectiveness • Prenatal HIV screening • Averts ~1500 cases of neonatal HIV per year • Cost saving • HIV antibody testing of 15 million blood donations • Averts ~1500 HIV infections per year • Costs $3,600 per QALY • Pooled RNA screening for HIV and HCV • Averts 4 HIV and 56 HCV infections per year • Costs $4.3 million per QALY

  23. HIV Rapid Tests

  24. Role for Rapid HIV Tests • Increase receipt of test results • Increase identification of HIV-infected pregnant women so they can receive effective prophylaxis • Increase feasibility of testing in acute-care settings with same-day results • Increase number of venues where testing can be offered to high-risk persons

  25. HIV Testing Can Be Done in Unusual Places

  26. Rapid Lateral Flow Tests • Capture antibody or antigen immobilized as a line on nitrocellulose • Detector antibody or antigen is a gold particle or latex particle

  27. Generations of Rapid Tests • 1st Generation – Detect antibody to HIV with viral lysate • 2nd Generation – Detect antibody to HIV with recombinant proteins or synthetic peptides • 3rd Generation – Detect both IgG and IgM antibody to HIV • 4th Generation – Detect antibody and viral protein

  28. Detection of HIV by Diagnostic Tests

  29. Clearview® COMPLETE HIV 1/2 Uni-Gold Recombigen™ Multispot HIV-1/HIV-2 OraQuick Advance® Reveal® G3 Clearview® HIV 1/2 STAT-PAK®

  30. FDA-approved Rapid HIV Tests

  31. OraQuick Advance® HIV-1/2 • CLIA-waived for finger stick, whole blood, oral fluid • Store at room temperature • Screens for HIV-1 and 2 • Read time 20-40 minutes • Shelf life: 1 year

  32. Collect oral fluid specimens by swabbing gums with test device. Reduce hazards, facilitate testing in field settings.

  33. Insert device; test develops in 20 minutes.

  34. Reactive Control Positive HIV-1/2 Positive Negative Read results in 20 – 40 minutes.

  35. Uni-Gold Recombigen™ • CLIA-waived for finger stick, whole blood • Store at room temperature • Screens for HIV-1 • Detects IgG and IgM • Read time 10-12 minutes • Shelf life: 1 year

  36. Fingerstick with disposable pipette

  37. Add 1 drop specimen to well

  38. Add 4 drops of wash solution

  39. Positive Negative Read results in 10 minutes

  40. Clearview® COMPLETE HIV 1/2 • CLIA waiver for whole blood • Store at room temperature • Screens for HIV-1 and 2 • Read time 15-20 minutes • Shelf life: 2 years

  41. Obtain fingerstick blood sample

  42. Insert device into buffer vial.

  43. Read results in 15-20 minutes

  44. Clearview® HIV-1/2 STAT-PAK® • CLIA-waived for whole blood and fingerstick • Store at room temperature • Screens for HIV-1 and 2 • Read time 15-20 minutes • Shelf life: 2 years

  45. Obtain fingerstick specimen.

  46. Add 5 microliters specimen.

  47. Add 3 drops buffer to well.

  48. Read results in 15-20 minutes.

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