HIV Testing. ECHO Hep C. Judith Feinberg, MD June 22, 2017

Transcription

1 HIV Testing ECHO Hep C Judith Feinberg, MD June 22, 2017

2 Overview A few basics HIV epidemiology in the US HIV testing

3 Time course of HIV-1 infection symptoms HIV proviral DNA symptoms window period HIV antibodies HIV viral load HIV-1 p24 antigen / infection weeks years Time following infection

4 Phases of HIV Infection Acute Phase Chronic Phase AIDS Acute HIV Infection Adapted from: Hoffman C, et al. HIV Medicine

5 At what stage of disease is HIV frequently being transmitted to another person?

6 Estimated HIV Transmission Risk Exposure Route Risk Per 100 Exposures to an Infected Source Blood Transfusion 90% Needle-sharing (IDU) 0.67% Receptive Anal Intercourse 0.5% Percutaneous Needle Stick 0.3% Receptive Vaginal Intercourse 0.1% Insertive Anal Intercourse 0.065% Insertive Vaginal Intercourse 0.05% Receptive/Insertive Oral Sex 0.005%-0.01% Antiretroviral Postexposure Prophylaxis After Sexual, Injection-Drug Use, or Other Nonoccupational Exposure to HIV in the United States Recommendations from the U.S. Department of Health and Human Services. MMWR 54(RR02);1-20.

7 HIV Risk by Type of Exposure Sexual intercourse female-to-male transmission 1 in 700-3,000 male-to-female transmission 1 in 200-2,000 male-to-male transmission 1 in 10-1,600 fellatio largely unknown Blood exposure needlestick (with AZT PEP) 1 in 200 (1 in 10,000) needle-sharing 1 in 150 transfusion of infected blood 95 in 100 Mother-infant transmission without AZT treatment 1 in 4 with AZT treatment <1 in 10 with combination antiretroviral therapy <1 in 50

8 Southeast Indiana: Recent Scott County HIV/HCV Outbreak* Cincinnati * to date: 210 HIV+, 87% HCV+ in Austin, a community of ~3,000

9 Demographic Characteristics of Scott County of all 92 counties in Indiana, it ranks 92 nd for health status limited access to healthcare; few providers 9% unemployment 19% poverty rate 21% without a high school diploma Brooks JT. The evolving epidemiology of HIV infection in persons who inject drugs: Indiana CROI; Boston, MA; February 22-25, 2016, abstract 132.

10 more than 50% are in Appalachia

11 West Virginia Counties at Risk for HIV and/or Hepatitis C Outbreak 28 of 220 high-risk counties are in WV (13% of US total) WV had 2 nd highest number of risk counties in the US (KY is #1 with 54, 25% of US total)

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14 Revised CDC Recommendations for HIV Testing in Adults and Adolescents Routine, voluntary, HIV screening for all persons aged years, not based on risk If known risk (eg MSM, PWID), repeat annually Opt-out HIV screening Opportunity to ask questions Option to decline Consent for HIV test is part of general consent for care Separate consent not recommended Prevention counseling not required in conjunction with HIV screening Low-prevalence setting If yield <0.1%, continued routine screening not warranted but we need to know about HIV intro into PWID population Branson BM et al. MMWR Recomm Rep. 2006;55(RR-14):1-17.

15 Experience With Implementing Opt-Out Testing HIV Test Rates San Francisco Department of Public Health Tests Per 1000 Visits Written consent requirement for HIV testing eliminated (Policy Δ) Jan May Sep Jan May Sep Jan May Sep Number of positives increased 50% Trend Pre/Post Δ in Policy *P<.001 observed vs expected trend. Zelota NM. JAMA. 2007;297(10): Expected Trend if No Δ in Policy 95% CI for Trend Pre/Post Δ in Policy*

16 Screening for HIV older test required 2-stage testing: ELISA or EIA for broad antibodies that react with HIV, then confirmation by Western blot for antibodies to specific HIV proteins current test ( 4 th generation ) tests simultaneously for HIV antibodies and antigens advantage: narrows the window period when someone may be infected and infectious to others but specific antibodies have not yet developed from 6-10 weeks to less than 10 days

17 New HIV Testing Algorithm +HIV 1 & 2 4 th generation immunoassay HIV-1 Ab+ HIV-2 Ab+ HIV ½ Ag+ RNA RNA+: Acute HIV RNA-: HIV Neg

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19 Percent of Persons Ever Tested and Tested in the Preceding 12 Months - NHIS Ever tested Preceding 12 months Percent MMWR August 8, 2008

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21 Barriers to HIV Testing Belief that effective treatment does not exist Stigma Distrust of medical establishment Cost Health care providers unwillingness