Matching preven.on to epidemic types and evidence David Wilson and Marelize Gorgens World Bank 15 July, 2011
The three core HIV preven.on ques.ons we want program science to help us answer Where do new HIV infec-ons come from? What proven, feasible interven-ons do we have for each major source of new infec-ons? How do we implement, monitor and evaluate the delivery of proven feasible interven-ons for each major source of new infec-ons?
The first duty of program science Knowing our epidemics, understanding our last 1,000 infec-ons, understanding transmission dynamics And fundamentally, making sure the money follows the epidemic and the interven4ons follow the evidence
Global epidemic diversity Insufficient recogni-on of global epidemic diversity
Transmission sources vary widely by region 100% 80% 60% 40% 20% 0% AF CAR EE ASIA LA Heterosexual MSM IDU MTCT
Women a majority of those infected in one region - Africa N America W Europe E Asia Oceania E Europe L America S/SE Asia Caribbean Africa Total 21 27 27 30 31 32 37 50 50 59 0 50 100
Core program science focus on epidemic typologies Core program science dis.nc.on between CONCENTRATED and GENERALIZED epidemics Not based on arbitrary <> 1% prevalence thresholds, but transmission paxerns Epidemics CONCENTRATED if protec.ng SW, MSM, IDU would prevent wider epidemic Epidemics GENERALIZED if epidemics would persist despite effec.ve SW, MSM, IDU programmes
Most epidemics globally are concentrated
600 Asian epidemic are not driven by the general popula.on 500 High risk including clients From high risk to partner 400 Casual sex in general popula.on 300 200 100 0 1990 1995 2000 2005 2010 2015 2020
Can we respond effec.vely? Once we beeer understand our epidemics, can we respond effec-vely with proven approaches - experience sobering in both concentrated and generalized epidemics
Addressing concentrated SW epidemics Consider concentrated epidemics ini-ated by SW Asian epidemics are only ini-ated by sex work if: Men uncircumcised Many men visit sex workers (> 10%) Sex workers have many clients (> 20 weekly) Thus, first wave of epidemics in Asia - Thailand, Cambodia, India (outside North East) largely ignited by SW
HIV prevalence by percentage of men visi.ng sex workers, Asia
HIV prevalence by number of clients per sex worker
Addressing concentrated SW epidemics Concentrated SW epidemics - know what to do in real world at scale Have successfully checked numerous SW epidemics in virtually all regions perhaps the most robust single preven-on success globally
We know the elements of effec.ve SW interven.ons Six -ghtly interconnected components: Behavior change communica-on usually through peer educa-on Condom promo-on and provision Tailored sexual health services HIV tes-ng and counseling Solidarity and group empowerment A suppor-ve local and na-onal legal environment
However, the complexity of sex work in Africa poses a challenge Clients per week 28 18 2-3 57% 40% 37% 29% 15% 15% Seaters Roamers Bar waitresses Mobile traders Students selling sex Beer brewers/ sellers Professional, self-identifying Non self-identifying
And concerted SW investments are elusive
Addressing concentrated IDU epidemics Throughout Asia and Eastern Europe, IDU drives HIV, directly and by injec-ng HIV into commercial sex networks Injec-ng drug use the spark plug that ignites sexual transmission, sex work the engine that maintains it - injec-ng drug use fuels HIV in sex work, fundamentally amplifying epidemic poten-al
Ini.ators of HIV epidemics in Asia Mainly SW ini-ated Mainly IDU ini-ated Mainly MSM
HIV higher in SW who inject drugs in Vietnam
Addressing concentrated IDU epidemics Yet real world experience discouraging Can we keep saying that harm reduc-on works, for example, in former Soviet Union or Asia, when we can t convince authori-es it is preferable to coercion? Limited progress towards large- scale harm reduc-on programs in major IDU epidemics Yet, if we can increase programs, we have inherent advantages - unlike condoms, which inhibit spontaneity, no- one WANTS to share dirty needles
Access to opioid subs.tu.on therapy in Eastern Europe and China 25 Number of OST recipients per 100 IDU 20 20 17 15 13 10 5 0 10 7 6 3 3 2 1 1 1 0 0 0 0 0
Addressing concentrated MSM epidemics Greatly underes.mated contribu.on of MSM to HIV transmission in developing countries Fron-ers photograph, 2008
MSM epidemics may incubate slowly then surge Abu- Raddad, 2009
HIV prevalence among MSM in La.n America 30 HIV Prevalence (%) 25 20 15 10 5 0 N MSM Mexico Trinidad & Tobago Bolivia Colombia Uruguay Ecuador Brazil Hondurus Paraguay Peru Argentina Guatemala Panama Nicaragua El Salvador Puerto Rico Population
HIV prevalence far higher in MSM than FSW in La.n America Argen-na Buenos Aires Ecuador Quito Bolivia Chile Colombia Provinces (7 ci4es) La Paz Santa Cruz Border ci4es with Argen4na San4ago Bogotá 0.0 0 5 10 15 20 25 30 % HIV prevalence Paraguay Peru Uruguay Guayaquil Other city ports (4) Asunción and 4 other ci4es Lima Provinces Montevideo Border ci4es with Brazil Venezuela 0.0 Isla Margarita 0 5 10 15 20 25 30 Female sex workers Men who have sex with men % HIV prevalence
HIV prevalence among MSM in Asia HIV Prevalence (%) 30 25 20 15 10 5 MSM Population 0 N Thailand India Indonesia Cambodia Nepal Vietnam China East Timor
HIV prevalence among MSM in India 20 18 17.6 17 16.4 16 14 % 12 11.8 11.7 10 8 7.4 8.4 7.9 7.4 6.6 6 5.6 4 2 0
% 10 HIV prevalence among MSM in China 8 6 5.7 5 2007 4 4.1 2009 2.8 2 1.4 2.1 0 <25 25+ Total
% HIV prevalence among MSM in Chongqing, China 25 20 19.2 15 16.3 10 10.4 10.8 5 0 2006 2007 2008 2009
% HIV prevalence among MSM in Sichuan, China 12 10.6 10 8 6 4.6 4 2 0.6 1 1.3 0 2003 2004 2005 2006 2007
Mauritania, 2007, 19.1% Egypt, 2006, 1% Egypt, 2008, 6.2% Senegal, 2005, 22% Senegal, 2007, 22% Mali, 2007, 37% Cote D Ivoire, 2006, 25% Ghana, 2006, 25% Nigeria, 2006, 13.4% Nigeria, 2007, 13.5% Sudan, 2005, 9.3% Sudan, 2008, 7.8% Uganda, 2008, 15% Mombassa, 2007, 25% Nairobi, 2008, 37% Zanzibar, 2007, 12.3% Zambia, 2006, 33% Malawi, 2008, 21% General Adult Prevalence 2007 Namibia, 2008, 12% Botswana, 2008, 20% Soweto, South Africa, 2008, 29% Cape Town, South Africa, 2007, 13.2%
HIV prevalence and incidence among MSM and FSW in Mombasa, Kenya 35 30 25 23 32 20 15 10 5 8.6 3.2 0 MSM FSW Prevalence Incidence
S-ll need to navigate between southern unwillingness to address male- male sexuality and northern tempta-on to frame response within western constructs of limited relevance to developing countries Addressing concentrated MSM epidemics Despite developed world successes, few developing country MSM programs have demonstrably reduced HIV incidence at scale In developing countries, know liele about how to reach hidden MSM, reduce s-gma, effect policy change and manage large- scale programs Easier in contexts open to homosexuality, such as India, China or Nepal, where implementa-on at scale is the greatest challenge than more repressive contexts
Addressing generalized epidemics Let s remind ourselves what generalized epidemics look like
60% 50% 40% 30% 20% 10% 0% 80% 60% 40% 20% 0% Sexual partnerships in Swaziland Casual sex Commercial sex Guards Drivers Soldiers Police Seasonal workers Sexual partnerships in Lesotho Soldiers Miners Drivers
Household HIV prevalence in Francistown, Botswana
Addressing generalized epidemics Do we have proven interven-ons in generalized epidemics? Consider this updated familiar summary of 50 HIV preven-on randomized controlled trials, including 37 completed/stopped studies, with HIV incidence end- points
Results of HIV preven.on trials Intervention Number Completed/ Stopped Microbicides 12 10 1 Behavior change 9 8 0 STI treatment 8 7 1 HIV vaccines 5 4 0 PEP 5 1 0 Male circumcision-male acquisition 3 3 3 HIV treatment as prevention 3 1 1 PREP 5 5 4 Total 50 37 10 Effective
Addressing generalized epidemics Four major challenges First, many trusted interven-ons treatment of sexually transmieed infec-ons, tes-ng and counseling, school and youth programs, condom promo-on - at best unproven, at worst disproven, for reducing HIV incidence
Addressing generalized epidemics Second, best proven interven-on, male circumcision, advancing slowly Yet immense poten-al safe circumcision in Eastern and Southern Africa countries could prevent 2+ million deaths Swaziland more providers than clients
Addressing generalized epidemics Third, major contributor to reduced HIV transmission in generalized epidemics is partner reduc-on have seen this in country amer country Yet, partner reduc-on investment, implementa-on and evalua-on s-ll neglected
10 Impact incidence changes HIV incidence (per 100pyar) 8 6 4 2 HIV incidence and behavior change in Zimbabwe 0 1980 1985 1990 1995 2000 2005 2010 Year 80 Proximate factors 60 Late 1990s Early/Mid 2000s % 40 20 0 15-19s men 15-19s women Men with had sex [DHS] had sex [DHS] extra-marital partners [DHS] Men paid for sex last year [DHS] Men with multiple concurrent partners [Manicaland] Men with casual partners in last month [Manicaland] Men using condom at last casual sex [DHS] Starting sex Multiple partnerships Condom use
Addressing generalized epidemics Fourth, what do we do about ART- based preven-on, including treatment as preven-on and PREP? How do we establish real world effec-veness, finance it and balance ART- based preven-on with obliga-on to treat the sick? WHO WILL PAY???
Conclusion why program science maxers so much CONCENTRATED formal SW epidemics preventable, but protec-ng informal SW in Africa, MSM and IDU in repressive contexts requires crea-ve approaches In GENERALIZED epidemics, core challenge to reallocate resources from unproven approaches to proven but sensi-ve approaches such as male circumcision and partner reduc-on and to figure out role of ART- based preven-on Common challenge is to align investments to epidemic dynamics and interven-ons to evidence Need clear dis-nc-on between contexts where we have the evidence and the challenge is implementa-on, implementa-on, implementa-on (most concentrated epidemics) and contexts where we lack decisive evidence (behavior change in hyper- epidemics)