A divergent tale of two citiesWhy HIV control in men who have sex with

men may have differed between London and San Francisco since 2006?

Colin Brown BSc MSc (Epi) MBChB MRCP FRCPath

CS Brown1,2, M Das3,4, L Hsu4, I Hall5, A Brown1, A Aghaizu1, P Birrell1, N Carraher4, S Desai1, J Hecht6, G Hughes1, D Mercey7, A Nardone1, T Packer4, F Post2, A Zaman1, Z Yin1,

N Gill1, V Delpech1

1 2 3 4 5 6 7

Acknowledgements

• Sincere thanks to all colleagues who have generously contributed their time, expertise, and on occasion, unpublished data in London and San Francisco

• All the men who participated in the various behavioural surveys

Background & Methods• HIV endemic in both settings

– 24% prevalence SF (64,000 MSM); 9% London (234,000 MSM)• Similar total prevalent numbers diagnosed

– 13,000 SF; 14,000 London (2010)• Recent treatment differences

– ART initiation at any CD4 count SF; ≤350 cells/μL London

• SF decline in the undiagnosed, new diagnoses & incidence estimates – London largely static

• Extensive surveillance/behavioural data from 2004– Evaluate how differences in risk behaviour, testing and treatment

coverage may account for the divergent trends

2006 2007 2008 2009 2010 2011 2012 20130

200

400

600

800

1000

1200

1400

1600

0

100

200

300

400

500

600

700

800

London new diagnoses

SF new di-agnoses

London rate

SF rate

Year

Num

ber o

f new

dia

gnos

es p

er y

ear

Rate

per

100

,000

MSM

New diagnoses -increasing in London, decreasing in SF

Sources: SFDPH, PHE MPES, *Data as of Jan 2014

*

200420052006200720082009201020110

5

10

15

20

25

30

35

40

0

5

10

15

20

25

London Undiagnosed % SF Undiagnosed %London Recent % (RITA) SF Recent % (BED)

Year

Und

iagn

osed

%

Rece

ntly

infe

cted

%

Incidence, undiagnosed and recency estimates – decreasing in SF

2007 2008 2009 2010 20110

200

400

600

800

1000

1200

Year

SF

inci

denc

e es

timat

es

(rat

e pe

r 100

,000

MSM

)

0

500

1000

1500

2000

2500

3000

Year

Lond

on in

cide

nce

es-

timat

es (t

otal

num

-be

rs)

Sources: NHBS, Birrell (Lancet ID, 2013), PHE MPESSources: SFDPH, Phillips (PLoS One, 2013)

London

SF

Decrease in SF undiagnosed robust

to sensitivity analysis:

• Incidence estimates

• New diagnoses• Inmigration

estimates• Deaths

Comparable MSM hubs – intensive interventions could be replicated

Vauxhall Castro

HIV Epidemiology London, 2011, HPA HIV Report, 2011, SFDPH

Median CD4 and age at diagnosis – similar across both settings

2006 2007 2008 2009 2010 201120

22

24

26

28

30

32

34

36

38

40

350

370

390

410

430

450

470

490

510

530

550

London median age SF median ageLondon median CD4 SF median CD4

Year

Med

ian

age

at d

iagn

osis

Med

ian

CD4

coun

t at d

iagn

osis

R2 – 0.916

Sources: CDC, PHE MPES

Higher frequency of community sexual health tests

Testing patterns – more regular testing in SF

2004 2008 2011London

Tested <1 year 42.8 51.4 58.2

Tested ever 82.2 88.4 91.8

San Francisco

Tested <6 months 44.1 55.2 57.8

Tested <1 year 69.0 73.0 72.0

Tested ever 96.0 96.5 97.2

Higher frequency of self-reported testing Sources: Gay Men’s Sexual Health Survey, NHBS

2009 2010 2011London

Total numbers 25,801 30,529 37,010

% negative MSM tested 12.1 14.1 16.9

San Francisco

Total numbers 13,259 15,240 14,777

% negative MSM tested 26.4 30.4 28.9

Sources: GUMCAD, SFDPH HIV Prevention Department

Retest SF 6 months (28%); London 12 months (39%)Sources: Thorton, Magnet (unpublished)

Self-report Actual tests

2004 2005 2006 2007 2008 2009 2010 20110

10

20

30

40

50

60

70

% M

SM re

porti

ng u

npro

tect

ed a

nal s

exSelf-reported condomless sex – higher

risk in London HIV negative MSM

Source: Gay Men’s Sexual Health Survey Sources: STOP AIDS Project, NHBS

London:12m San Francisco:6m

-ve (discordant)

+ve(discordant)

+ve (all UAI)

-ve (all UAI)

Year

2004 2005 2006 2007 2008 2009 2010 20110

10

20

30

40

50

60

70

+ve (discordant)

-ve (discordant)

-ve (all UAI)

+ve (all UAI)

2006 2007 2008 2009 2010 20110

500

1000

1500

2000

2500 London HIV positive gonorrhoea London HIV negative gonorrhoea SF HIV positive gonorrhoea SF HIV negative gonorrhoea

Year

STI r

ate

per 1

00,0

0 M

SM

2006 2007 2008 2009 2010 20110

500

1000

1500

2000

2500

3000

3500 London HIV positive syphilis London HIV negative syphilis SF HIV positive syphilis SF HIV negative syphilis

STIs largely concentrated in HIV positive MSM in SF

Sources: SFDPH STD, PHE GUMCAD

Diagnosed Linkage <12 months

Retention Viral supression0

20

40

60

80

100

London - 2010

Diagnosed Linkage <12 months

Retention Viral supression0

20

40

60

80

100

San Francisco - 2010

Infected

Diagnosed

Linkag

e <12 m

onths

Retention

Viral su

pressio

n0

20

40

60

80

100

London - 2010

Infected

Diagnosed

Linkag

e <12 m

onths

Retention

Viral su

pressio

n0

20

40

60

80

100

San Francisco - 2010

Care cascade differences

London’s main problem is the static undiagnosed population

Increasing retention in SF may allow for greater reduction in transmission

Sources: PHE SOPHID/MPES Sources: CDC & NHBS

% MSM suppressed among diagnosed

Sources: PHE SOPHID/MPES, CDC

2006 2007 2008 2009 2010 20110.0

10.0

20.0

30.0

40.0

50.0

60.0

70.0

80.0

90.0

San Francisco London

Year

% su

ppre

ssio

n am

ong

diag

nose

d M

SM a

live

the

follo

win

g ye

ar

R2 – 0.970

Substance use and other markers of high risk – increasing in London

• HCV reinfection rate up to 25% in 2 years in LondonSF HCV prevalence stable, likely older infections

• Recreational drug use prevalent during London Shigella fleneri outbreak– 76% recreational drug use– 31% injection drug use

• London - 13.6% crystal meth use last year & 3.5% injection drug use (12% per year in SF, and decreasing)Sources: Martin, AIDS, 2013; Gilbart, Lancet, 2014; Bourne, SIGMA, 2014 ; Raymond, JAIDS, 2013

SF social marketing

Source: STOP AIDS Source: STOP AIDS

Summary• Caveats - MSM denominator assumptions; comparable reporting

mechanisms; shared population characteristics• Apparent reduced proportion of undiagnosed HIV and new

diagnoses in SF may be due to:– Higher proportion of HIV-negative MSM reporting more regular HIV testing

(and possible retesting)– Safer sex practices - increased condom use, disclosure, and seroadaptive

practices– Culture of ‘positive’ openness

• Critical importance for prevention of very high rates of HIV testing, awareness, and disclosure of HIV status

• Safety myth of negative-negative serosorting needs aggressively challenged

Key next questions

• How best to implement novel risk reduction strategies in London? – Achieving SF’s testing patterns/status disclosure challenging– Larger, less dense, lower prevalence population – Campaign methods: social media, community marketing, other?

• Who is driving transmission in London vs SF?– Acute, undiagnosed or untreated infections – Contribution of inmigration (~20% new diagnoses in 2011)

• Behaviour data needs disaggregated by:– Treatment uptake– Viraemia – PreP use

Selected data sourcesLondon• Gay Men’s Sexual Health Survey (UCL)• Gay Men’s London Gym Survey • Gay Men’s Sex Survey (SIGMA)• National Survey of Sexual Attitudes and

Lifestyles II• Office of National Statistics• PHE Genitourinary Medicine Clinic

Activity Dataset (GUMCAD)• PHE HIV and AIDS New Diagnoses

Database (HANDD)• PHE Multi-Parameter Evidence

Synthesis (MPES)• PHE Recent Infection Testing Algorithm

(RITA)• PHE Survey of Prevalent HIV Infections

Diagnosed (SOPHID)

San Francisco• CDC HIV Surveillance data• Consensus Meetings on HIV/AIDS

Incidence and Prevalence in California

• National HIV Behavioural Surveillance Survey

• San Francisco AIDS Foundation• SFDPH STD data• SFPDH HIV Prevention data• SFPDH HIV Epidemiology data• STOP AIDS Project• UCSF• United States Census Bureau

Literature review