05 gilbert marksummit 2011

1

Sustaining an Effective Response to Acute HIV Infection Among Gay Men

BC Gay Men’s Health Summit – November 3, 2011Mark Gilbert

BC Centre for Disease Control

Contributors

Michael Kwag Malcolm Steinberg Darrel Cook Mel Krajden

2

3

CIHR Acute HIV Study Team and Collaborators

HIV Emerging Team

National HIV and Retroviral LaboratoriesJames Brooks

National Lab for HIV GeneticsPaul Sandstrom Terry Trussler, Rick Marchand, Olivier Ferlatte

North Carolina HIV/STD PreventionPeter Leone

Josephine McIntoshMathematics Department

Daniel Coombs

STI/HIV Prevention & ControlMichael Rekart, Mark Gilbert, Malcolm

Steinberg, Michael Kwag, Bill Coleman, Gina Ogilvie, Melanie Achen,

Glenn Doupe, Daphne Spencer, Cory Genereaux, Daniel Grace, Sarah Chown,

Robin ParryMathematical Modeling

Babak Pourbohloul, Jennifer Lindquist, Flavia Moser

Laboratory ServicesMel Krajden, Darrel Cook, Wendy Mei

EpidemiologyDavid Patrick

Benedikt Fisher

Elgin LimJody Jollimore, Hans BosgoedWayne Robert

Captain Snowden

Richard Rothenberg

Recruitment Sites12th Avenue, Bute Street, Spectrum Health, 3 Bridges, Dr Richard Taylor, Cook Street, HIM SHC

Presentation Outline

Background (Acute HIV, Window Periods) Overview of CIHR study & social marketing

campaigns Description of the impact of introducing testing for

acute HIV infection (pooled NAAT testing) Review of current policy options & next steps

4

Why is acute HIV important? HIV prevention

– High viral load = high probability of transmission– Earlier diagnosis & potential for behaviour change– Active sexual networks

(Brenner JID 2007; Fraser CROI 2006; Galvin Nature Rev Micro 2004; Hayes JID 2005)

Appearance of markers of HIV infection

(BCCDC 2010)

Window period – “standard testing”

3 - 4 weeks

Window period – pooled NAAT

10-12 days

Not easy to understand, or explain!

Window periods HIV test options Acute HIV and why important

Ramifications?– Delays in testing (wait 3-6 months to test)– Not taking advantage of current tests

10

December 2009 - Feb 2010

12

August 2011 to present

13

Relevant CIHR study objectives To diagnose acutely infected gay, bisexual and other MSM using

innovative laboratory testing methods (NAAT and 4th generation EIA tests)

To promote HIV testing as a first response to risk events through community based social marketing initiatives

Methods – HIV positive cohort Mixed-methods (quant/qual), longitudinal cohort study Recruitment: April 2009-December 2012 Eligibility:

Gay or MSM, 19 or older Acute or recent HIV diagnosis

Study sites: 7 clinics in Vancouver– Gay men as clients; history of frequent HIV diagnosis in gay men

Intervention: Enhanced HIV testing protocol (NAAT) Enhanced support: Professional and Peer-based counseling

Current participants: 23 (9 acute; 14 recent)

14

For this analysis

Used PHSA laboratory testing data to describe the impact of introducing pooled NAAT testing at the CIHR study sites

Compared pre- and post-pooling periods

15

New positive HIV tests, Men 19+ years CIHR study sites

0

5

10

15

20

25

30

Other

Recent

Acute

Pooled NAAT

Summary of HIV test results from AHI CIHR project sites (Q1 2007 – Q2 2011)

Pre-Pooling(Q1 2007 – Q4 2008)

Post-Pooling**(Q1 2009 – Q2 2011)

% Change

Test Volume* (specimens)

14,178(~525 per month)

16,075(~600 per month)

13% increase

Test Volume* (individuals)

10,284 11,056 8% increase

All New positive HIV Cases

173 155 10% decrease

Acute HIV Cases 15 34 127% increase

Recent HIV Cases 36 40 11% increase

For the acute HIV cases identified post-pooling, 14 (41%) would have been missed if only the standard HIV test algorithm had been used.

* Negative Point of Care tests not included. **HIM clinic added Sept 2010

Factors explaining increase?

Introduction of pooled NAAT testing Impact of social marketing campaigns Increased testing volume Other?

18

Conclusion?

Introducing Pooled NAAT testing is effective! – Diagnoses made that would otherwise be missed– Greater opportunities for prevention of HIV transmission

Valuable prevention tool for gay men

What now? The study ends December 2012…

19

Acute HIV “Buzz”

Potential benefit recognized from outset by community and public health partners

These results have been discussed within STOP Considered a success

20

Option1 : Sustain or expand pooled NAAT…

Problem: $$$ Not cost-effective to implement province-wide Looking into:

– Sustaining beyond 2012 at the study sites– Expansion to select HIV testing sites with high diagnosis

rates

21

… and/or Option 2: 4th generation screening tests

2 - 3 weeks

… and/or Option 2: 4th generation screening tests

Implemented in Quebec Cheaper test, could implement across province Reduces window period of “standard” test, would detect

more acute HIV infections than 3rd gen EIA However, would miss many acute HIV infections as well

– We looked to see how well two types of 4th gen EIA tests did at detecting HIV in the 14 men with acute HIV infection diagnosed through pooled NAAT: approximately 40-70% were missed.

Gay men are more likely to test during the acute phase of HIV infection

What next? Merits to both options (our preference: both) Preparing appropriate policy documents & business

case for decision-makers Conducting further head-to-head comparison of

pooled NAAT and 4th gen screening tests, to better understand impact (2012)

Publication of findings & knowledge translation

24

What do you think?

Contact Info: – Mark Gilbert, Co-Principal Investigator

• [email protected] – Michael Kwag, Research Project Manager

• [email protected]• 778-886-7781