HIV Testing in Medical Settings

Mark Thrun, MD

Denver Public Health

Mark.thrun@dhha.org

Prevention is Spectrum

Spans the spectrum of care

of persons at risk for HIV

Positive HIV TestScreening for

STD/HIV

Prevention discussions/ counseling

Personal assessment/

acknowledgement of risk

Ongoing personal behavior modification

Prevention is Spectrum

Spans the spectrum of care

of persons living with HIV

Positive HIV Test

Linkage into HIV

care

Prevention discussions/screening

in care

Compliance with care

Return to HIV care

Updated CDC recommendations for HIV screening in clinical care settings• All patients between 13 – 64 years of age –

an initial screening test

• All patients being evaluated for possible TB

• All patients being evaluated for possible STD

• Annual screening for persons at increased risk– Men who have sex with men– Persons with > 1 sexual partner– Drug users

Awareness of Serostatus Among People with HIV and Estimates of Transmission

~25% Unaware

of Infection

~75% Aware of Infection

People Living with HIV/AIDS: 1,039,000-1,185,000

New Sexual Infections Each Year: ~32,000

Accounting for: ~54% of New

Infections

~46% of New

Infections

Marks, et alAIDS 2006;20:1447-50

Uni-Gold Recombigen

Multispot HIV-1/HIV-2

Reveal G2

OraQuick Advance

Knowledge is Power

Persons aware of HIV infection less likely to have risk of transmission

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SHAS

SHAS

SHAS

SHAS

Clear

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Clear

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HERS

MACS

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Percent Reduction in Prevalence UAVI in HIV + Aware v. Unaware

Marks, JAIDS 2005

Source of HIV Tests and Positive Tests

HIV+ tests**HIV tests*

17%44%Private doctor/HMO

27%22%Hospital, ED, Outpatient

2%

6%

5%

9%

21%

0.7%Drug treatment clinic

0.1%STD clinic

0.6%Correctional facility

5%HIV counseling/testing

9%Community clinic (public)

*National Health Interview Survey, 2002**Suppl. to HIV/AIDS surveillance, 2000-2003

• 38% - 44% of adults age 18-64 have been tested • 16-22 million persons age 18-64 tested annually in U.S.

Many persons living with HIV seek care outside HIV clinic

• HIV clinic 2006 : 220 people at risk for transmitting HIV – 1000 patients x 22% high risk

• STD clinic 2006: 167 people at risk for transmitting HIV – Clients asked HIV status or offered HIV test

• ED estimate 2006: 315 people at risk for transmitting HIV – 3.5% in DH ED HIV+; 0.7% previously unrecognized

infection x approx 45K unique visits/yr(Goggin, J Emerg Med, 2000)

Emergency Department

ED Testing and Counseling

Haukoos, Acad Emerg Med, 2007

Targeted testing

Tested for HIV 681

HIV Positive 15 (2.2%)

Linked into Care 12 (80%)*

* 1 died, 1 incarcerated, 1 homeless

Routine HIV TestingOpt-out Consent

STD Clinic

Changes in the clinic re: HIV testing• HIV testing acceptance and HIV test positivity was

evaluated for 4 time periods:– Period 1: The year before introduction of rapid testing

• December 2002 – November 2003

– Period 2: The 6 months following introduction or rapid testing, before logistical adjustment in the clinic and discontinuation of the standard test

• December 2003 – May 2004

– Period 3: The 10 months following logistical adjustment, but before introduction of the electronic medical record and opt-out testing

• June 2004 – March 2005

– Period 4: The 6 months following opt-out testing• April 2005 – September 2005

HIV Testing Acceptance

60

65

70

75

80

85

90

95

100

Period 1 Period 2 Period 3 Period 4

MSMNon-MSM

Period 1: Before introduction of rapid testingPeriod 2: Following Period 1, before logistical adjustmentsPeriod 3: Following Period 2, before opt-out consentPeriod 4: After Introduction of opt-out

%

HIV Positivity

0

0.5

1

1.5

2

2.5

3

3.5

4

MSM Non-MSM

Period 1Period 2Period 3Period 4

Period 1: Before introduction of rapid testingPeriod 2: Following Period 1, before logistical adjustmentsPeriod 3: Following Period 2, before opt-out consentPeriod 4: After Introduction of opt-out

%

Rapid Testing Trends9/01/03 – 9/31/04

0

100

200

300

400

500

600

700

800

900

DMHC

CTRS

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of

Te

sts

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rmed

Rapid testing only.

Change in clinic logistics

Impacts of Rapid Testing

Denver Metro Health Clinic

Percentage of patients who received their positive test results:

Before: After:

66% 100%

Caveat: False positive tests

Positive predictive values

Single EIA

Test Specificity

HIV Prevalence

Predictive Value, Positive Test

10% 99% 98%92%5% 98% 96%85%2% 95% 91%69%1% 91% 83%53%

0.5% 83% 71%36%0.3% 75% 60%25%0.1% 50% 33%10%

OraQuick Reveal

99.9% 99.8%99.1%

97%95%87%77%63%50%25%

Uni-Gold

99.7%

Caveat: Routine HIV testing may mean more staff time

Lessons in positive predictive valueExample 1: Test 1,000 persons

Test Specificity 99.6%HIV Prevalence 10%

True Positives: 100 False Positives: 4Positive predictive value: 100/104 = 96%

Example 2: Test 1,000 personsTest Specificity 99.6%HIV Prevalence 0.4%

True Positives: 4 False Positives: 4Positive predictive value: 4/8 = 50%

Caveat: What happens when people test positive

Disposition and Linkage into Care

Haukoos, Acad Emerg Med, 2007

Coordination of referrals

Haukoos, Acad Emerg Med, 2007

Linkage to care/Additional prevention counseling

Patients referred to LTC staff:366

Confirmed linked to care:220 (71%)

Linkage to Care: Denver 2005 - 6/2007

Patients seen by LTC staff:311

Training Needs Related to Expansion of Testing

• New technologies require staff to be brought up to speed

• Emphasis of training may need to shift– Less didactic class time– More technical assistance

• Training must be ongoing and collaborative

• Training needs may fall outside “target” topic area: e.g. testing and linkage to care

Acknowledgements

Kees Rietmeijer

Jason Haukoos

Emily Hopkins

Bill Burman

Tom Deem

Marshall Gourley

Reina Lopez

Ryan Westergaard