HIV Australia | Vol. 13 No. 2 | July 2015
Sean Slavin
SEAN SLAVIN explores the impact of treatment as prevention on health promotion, canvassing the views of people from Australian HIV organisations and other health experts.
Treatment as Prevention (TasP) has been discussed for several years in light of increasingly reliable scientific research about the efficacy of TasP, the social and sexual practices of communities and individuals affected by HIV.
Optimising TasP is a goal of the current national HIV strategy, which aims to ‘work towards achieving the virtual elimination of HIV transmission in Australia by 2020’; and to ‘increase the proportion of people living with HIV on treatments with an undetectable viral load’.1
Over the past six months, AFAO undertook consultations with its members and other experts to identify the key health promotion challenges relating to TasP and its place within ongoing combination HIV prevention efforts.
Sixteen interviews were conducted in total; this article summarises some of the main themes which emerged.
Background
The goal of antiretroviral treatments (ARVs) is to reduce HIV viral load. The viral load test is a measurement of the level of HIV in the blood, as well as a proxy marker for HIV infectiousness.
Thus, ARVs have long been understood as an effective prevention tool in a range of contexts including mother-to-child transmission, occupational exposure to HIV and sexual exposure.
The issue of sexual infectiousness received significant attention in 2008, when the Swiss Federal AIDS Commission published a statement that declared under certain conditions, people with HIV who have an undetectable viral load (UDVL) are not infectious to their sexual partners.
The conditions included the absence of sexually transmissible infections (STIs) and UDVL for at least six months prior.
The statement specifically referred to ‘stable’ heterosexual couples, which caused uncertainty about the implications for gay male serodiscordant couples.2
While the Swiss statement covered the implications of UDVL for individuals and couples, other discussions around the same time focused on the potential population effects.
In Australia, many in the HIV sector expressed concern about the potential risks of substituting UDVL for condom use, with one modelling study predicted a fourfold increase in HIV incidence among gay men if rates of condom use declined under these circumstances.3
Some scientists working in settings with low rates of condom use, testing and treatment took a more positive view about the potential benefits to population health of increasing both testing and treatment.
The province of British Columbia in Canada adopted a ‘test and treat’ strategy4 and a model was developed for high prevalence epidemics in sub-Saharan Africa.
Granich and colleagues5 theorised that with universal testing and immediate treatment following diagnosis it would be possible to eliminate HIV transmission.
While Granich’s argument used a hypothetical model, many recognised the potential to both reduce HIV incidence and to scale up clinical and treatment services for people with HIV, who had been chronically underserviced in many contexts.
Thus a population health approach to prevention also has benefits for individual people with HIV by reducing the morbidity and mortality associated with undiagnosed and untreated HIV cases.
The most notable example of such a program is in San Francisco where great success has been achieved in increasing testing and linkage to care.6
At the time, population health discussions relied on a range of evidence that suggested ARV treatment reduced the risk of transmission to varying degrees.7
What was missing was robust evidence that gave a more precise figure for the degree of individual risk reduction. This arrived in August 2011, with results from the HPTN 052 trial showing that UDVL worked to reduce the incidence of HIV by 96% among heterosexual couples.8
Evidence for homosexual couples came in 2014, with the release of interim results from the PARTNER Study.
At the study’s halfway point, analysis indicated that the risk of HIV transmission in anal sex when the HIV-positive partner had an UDVL was 1%.
When asked to clarify what this meant in practice, the researchers responded that their best estimate of the actual risk was zero.9
Many people with HIV and their HIVnegative partners are highly engaged with these scientific discussions and want to better understand and use the technology to help manage HIV risk in the context of their lives.10
What does ‘Treatment as Prevention’ mean in an Australian context?
A population versus an individual approach
Respondents to AFAO’s consultation on TasP largely saw it as being both a population health and an individual approach to HIV prevention; however, they usually emphasised one aspect over the other, depending on their particular concerns or those of their communities.
A representative from an HIV-positive organisation spoke about the potential of TasP to allow people with HIV to more fully enjoy their sex life without worrying about transmitting HIV or needing to use condoms.
This respondent said that results of HPTN 052 and the PARTNER study meant that for people with UDVL, condoms were no longer necessarily the preferred or even the best method of HIV prevention.
Two social researchers working with serodiscordant couples suggested that individuals and couples are grappling with the personal implications of population health discussions about TasP in different ways.
They said that some research participants are using TasP to support condomless sex, while others see it as something to be used in combination with condoms, providing even greater protection against HIV.
Another social researcher said that while TasP has been promoted as an HIV prevention measure, this has primarily been through ‘test and treat’ programs to reduce the ‘community viral load’, but without necessarily engaging in detailed discussion about the implications of treatment for individual sexual practice.
Other respondents were cautious about TasP for individuals and emphasised that consistent condom use remains the cornerstone of HIV prevention in Australia.
They emphasised the role of TasP within combination prevention, aiming to increase testing and treatment alongside condom reinforcement messages.
This additive approach was then extrapolated to individual circumstances where TasP was seen as additional to condoms.
There was broad agreement that increasing the range of ways to reduce risk was a positive step, but whether individuals decided to use more than one option, or only one, was ultimately up to individuals to decide.
This decision is informed by available information and guided by a number of factors including personal disposition, comfort or discomfort with risk, personal sexual preferences regarding condoms and the ways in which couples enact intimacy, care and safety.
Is TasP an effective standalone safe sex strategy for individuals?
According to a senior clinical and epidemiological researcher, it is possible to recommend TasP as a standalone safe sex strategy for individuals under certain conditions; these include restriction of the approach to individuals in ongoing relationships, where the person with HIV is adherent to medication and has maintained and monitored an UDVL for six months or longer.
The principal reason given for limiting the strategy to couples in regular relationships was that TasP relies on a high level of communication about technical issues such as viral load, trust that the person with HIV is adherent to medication and truthful about their viral load results. Managing this could be difficult in casual sexual encounters.
Notwithstanding this, some respondents wanted to guard against the development of a normative view of what constitutes a ‘good’ serodiscordant relationship because this could stigmatise those who have casual sex or open relationships.
Treatment commencement
The question of treatment commencement was discussed by several respondents and there was broad agreement about a set of principles that guide our approach on this issue:
- The decision to start life-long treatment is significant for most people. Being well prepared is a crucial determinant of ongoing adherence and success. A senior clinician and medical researcher said that preparedness includes a range of clinical and psycho-social concerns.
- Compulsion or coercion to commence treatment should not be a feature of TasP. Informed individual decisions to defer treatment should be respected.
- Treatment should be universally available and easily accessible to all individuals who are willing and prepared to start. An ongoing concern exists for people with HIV living in Australia whose access to treatment is limited due to Medicare and the Pharmaceutical Benefits Scheme (PBS) ineligibility.
Since conducting the consultations, the START study has shown that treatment is beneficial for people with recent infections and high CD4 counts.
This removes uncertainty about the balance of individual risks and benefits when treating people with CD4 cell counts at levels higher than 500 and helps health promoters to further focus on treatment preparedness.
What does TasP involve for individuals?
TasP requires a high level of adherence to medication—higher than 90% of doses per month. TasP also requires regular monitoring of viral load. Current clinical practice involves testing at three month intervals and this was regarded as sufficient to support a TasP approach.
Less frequent testing among stable patients may need to be reviewed if a TasP arrangement exists.
The meaning of an UDVL was cited as variable, socially and culturally contingent and needing clarification through health promotion (see for example: Gagnon and Guta, 201411 and Race, 200112).
One social researcher described a conflation among some survey respondents between HIV serostatus and undetectability.
Some HIV-negative people believe themselves to be undetectable and some HIV-positive people with UDVLs believe themselves to be HIV-negative.
Meanwhile, some HIV-positive people are inventing new ways to describe their status, especially in online hookup environments that attempt to frame ‘undetectable’ as a new HIV status, signalling health and reduced infectiousness.13
Viral load blips are not uncommon, particularly as tests have become more sensitive. Very low readings are thought to be clinically insignificant and probably not a risk for transmission when the blip is marginal (i.e. <400 copies/ml).14
Another social researcher reported that many of their research participants held folk beliefs about viral load and the factors affecting it. These included a common belief that other infections like colds could lead to an increase in viral load.
Interestingly, people relying on TasP for sexual risk reduction may vary their sexual practice around such periods to reduce risk in other ways.
This suggests that risk reduction within couple relationships can be understood as a process involving ongoing communication and adjustment that is responsive to changing circumstances.
A number of respondents expressed concern about the possibility of creating division or hierarchy among people with HIV according to viral load.
While HIV-positive people with detectable viral loads should not be stigmatised or made to feel inadequate, one of the limitations of TasP for individuals is the need for an UDVL.
Regular STI testing was also regarded as important. The recommended frequency depends on behavioural risk but Australian guidelines suggest at least annually for people with HIV (both heterosexual and homosexual) and quarterly if other risk factors are involved (see the Australian STI Management Guidelines at: www.sti.guidelines.org.au).
While the residual risk of HIV transmission in the context of TasP may be small, it is nonetheless important that HIV-negative partners in serodiscordant relationships establish a regular HIV testing routine and are aware of symptoms associated with HIV seroconversion illness.
There was a broadly shared view that individual TasP practices should include discussion and understanding of the approach by both partners in order to ensure informed consent to the approach. This inevitably involves disclosure of HIV status by the HIV-positive partner.
The most compelling reason cited for limiting promotion of TasP as the primary risk reduction approach to regular relationships was that complex discussions including disclosure could more reasonably occur between partners who know or are getting to know each other.
Given the persistence of stress about disclosure among people with HIV, there was broad support for health promotion to provide more specific support around this issue.
Several respondents raised concerns about the potential legal implications of individuals using TasP as an alternative to condoms, in some jurisdictions.
There was, however, endorsement of the harm reduction principle that HIV health promotion should offer advice to empower individuals to reduce the risk of HIV, even when it involves illegal behaviour.
There was also acknowledgement that health promotion must address the reality that many couples do not like using condoms and awareness about TasP as an alternative is steadily increasing, in any case.
A number of respondents discussed the positive potential that might arise from a relational and shared approach to treatment and prevention within couples.
Mostly, management of HIV takes place outside the context of relationships, in the clinic and the involvement of HIVnegative partners in these practices is generally limited to understanding their partner is well and perhaps being kept informed of viral load results.
Given that TasP is a prevention tool that both partners may rely upon, it is worth considering the health information needs of HIV-negative people, including about HIV-related health and treatments.
This has the potential to lighten the burden for the person with HIV and engender confidence in the HIV-negative partner.
Conclusion
The prevention benefits of treatment continue to be a crucial feature of combination prevention in pursuit of national goals to significantly reduce HIV incidence.
Treatment as prevention also has potential to reduce HIV-related stigma by reconfiguring what it means to have HIV.
Some people with HIV are already claiming ‘undetectable’ as a new HIV status that encompasses health and reduced infectiousness.
There is growing interest among people with HIV and their sexual partners about the potential of TasP as an individual safe sex strategy that may or may not also include condoms.
This represents an opportunity for HIV health promotion to develop clear and consistent advice on how to do this safely.
This requires improved HIV health literacy among HIV-negative partners of people with HIV, including more detailed information on treatments, viral load and condom and non-condom based sexual risk reduction.
Providing guidance to people with HIV and their partners about sexual risk reduction without condoms may continue to cause concern, including for legal, political and epidemiological reasons.
But providing such guidance draws on strong scientific evidence about the safety of the practice and has potential to assist those individuals and couples wanting better sexual intimacy, less self-stigma and reduced anxiety about transmitting HIV to their partners.
References
1Australian Government Department of Health. (2014). Seventh National HIV Strategy 2014–2017. Commonwealth of Australia, Canberra.
2 Vernazza, P., Hirschel. B., Bernasconi, E., Flepp, M. (2008). Les personnes séropositives ne souffrant d’aucune autre MST et suivant un traitement antirétroviral efficace ne transmettent pas le VIH par voie sexuelle. (HIV-positive individuals without additional sexually transmitted diseases (STD) and on effective antiretroviral therapy are sexually non-infectious.) Bulletin des médecins suisses, 89(5), 165–169. English translation retrieved from: www.edwinjbernard.com
3 Wilson, D., Law, M., Grulich, A., Cooper, D., Kaldor, J. (2009). Relation between HIV viral load and infectiousness: a model-based analysis. The Lancet, 372(9635), 314–320. doi: dx.doi.org/10.1016/S0140-6736(08)61115-0
4 Montaner, J., Lima, V., Barrios, R., Yip, B., Wood, E., Kerr, T., et al. (2010). Association of highly active antiretroviral therapy coverage, population viral load, and yearly new HIV diagnoses in British Columbia, Canada: a population-based study. The Lancet, 376(9740), 532–539. doi: dx.doi.org/10.1016/S0140-6736(10)60936-1
5 Granich, R., Gilks, C., Dye, C., De Cock, K., Williams, B. (2009). Universal voluntary HIV testing with immediate antiretroviral therapy as a strategy for elimination of HIV transmission: a mathematical model. The Lancet, 373(9657): 48–57. doi: dx.doi.org/10.1016/S0140-6736(08)61697-9
6 Das, M., Chu, P., Santos, G., Scheer, S., Vittinghoff, E., McFarland, W., et al. (2010). Decreases in community viral load are accompanied by reductions in new HIV infections in San Francisco. PLOS ONE, 5(6), e11068. doi: dx.doi.org/10.1371/journal.pone.0011068
7 Anglemyer, A., Rutherford, G., Easterbrook, P., Horvath, T., Vitória, M., Jan, M., et al. (2013). Early initiation of antiretroviral therapy in HIV-infected adults and adolescents: a systematic review. AIDS, 28 (Suppl 2), S105–S118 . doi: dx.doi.org/10.1097/QAD.0000000000000232
8 Cohen, M., Chen, Y., McCauley, M., Gamble, T., Hosseinipour, M., Kumarasamy, N., et al. (2011). Prevention of HIV-1 infection with early antiretroviral therapy. N Engl J Med., 365, 493–505. doi: dx.doi.org/10.1056/NEJMoa1105243
9 Rodger, A., Bruun, T., Weait, M., Vernazza, P., Collins, S., Estrada, V., et al. (2014). HIV transmission risk through condomless sex if HIV+ partner on suppressive ART: PARTNER study. Presentation delivered at the 2014 Conference on Retroviruses and Opportunistic Infections (CROI 2014), 3–6 March, Boston. Abstract 153LB.
10 Persson, A. (2010). Reflections on the Swiss Consensus Statement in the context of qualitative interviews with heterosexuals living with HIV. AIDS Care, 22(12), 1487–1492. doi: http://dx.doi.org/10.1080/09540121.2010.482122
11Gagnon, M., Guta, A. (2014). HIV Viral Load: A Concept Analysis and Critique. Research and Theory for Nursing Practice, 28(3), 204–227.
12 Race, K. (2014). Speculative pragmatism and intimate arrangements: online hook-up devices in gay life. Culture, Health & Sexuality, 17(4), 496–511. http://dx.doi.org/10.1080/13691058.2014.930181
13 ibid.
14 Taiwo, B., Bosch, R. (2012). More Reasons to Reexamine the Definition of Viral Blip During Antiretroviral Therapy. Journal of Infectious Diseases, 205(8), 1189–1191. dx.doi.org/10.1093/infdis/jis109
Dr Sean Slavin is an HIV Health Promotion Officer at AFAO.