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Treatment as prevention: cannot succeed without increased testing AND PRIMARY PREVENTION example from the United Kingdom? Dr Valerie Delpech Head of HIV surveillance Public Health England
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HIV team at Public Health England Andrew Phillips, UCL All the patients living with HIV as well as clinicians, health advisors, nurses, microbiologists, public health practitioners, data managers and other colleagues who contribute to the surveillance of HIV and STIs in the UK.
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Outline of talk Background to the UK epidemic Focus on MSM – group most at risk What does success look like? Trends in the HIV and STIs epidemic HIV care in MSM Models showing trends in HIV incidence and the undiagnosed Conclusions and fture projections
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HIV epidemic in the United Kingdom 100,000 people living with HIV 25,000 people remain undiagnosed Over half of infections concentrated in MSM and most are in London >80% of MSM acquire HIV in the UK NHS provides free and open access HIV testing, treatment and care HIV care is excellent 4 Presentation title - edit in Header and Footer
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5 HIV in the United Kingdom: 2013 Men who have sex with men (MSM) MSM remain the group most affected by HIV with 47 per 1,000 living with the infection (18% unaware). New diagnoses continued to rise and reached an all time high of 3,250 in 2012. This reflects both an increase in HIV testing and on-going transmission. 34% were diagnosed late (CD4<350) 29% had a concurrent acute STI (chlamydia, gonorrhoea and/or syphilis) at diagnosis HIV in the United Kingdom, 2012
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Optimal treatment uptake leading to elimination (decrease) in incidence (new HIV infections) in conjunction with elimination of AIDS and AIDS deaths and no impact on other STIs What is successful TasP?
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Granich RM et al, Lancet 2009; 373: 48–57 HIV incidence 7 2000 2020 2040
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8 Among approximately 77,600 persons living with diagnosed HIV infection in the UK 97% are linked to care after diagnosis within 3 months 95% are retained in care annually 92% of persons in need of treatment are on treatment 95% of persons on treatment achieve VL<200 copies/ml
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MSM in HIV care, UK 9Presentation title - edit in Header and Footer
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HIV and STI Department, Health Protection Agency - Colindale HIV and AIDS Reporting System
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Median CD4 count at diagnosis among MSM by age-group
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New diagnoses and one year mortality, MSM diagnosed with CD4>350 cells/mm 3
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New diagnoses and one year mortality, MSM diagnosed with CD4≤350 cells/mm 3
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Back-calculation method Annual HIV incidence in MSM in England & Wales 2001-2010, Birrell et al: Birrell P.J. Gill O.N., Delpech V.C et al (2013). HIV incidence in men who have sex with men in England and Wales 2001–10: a nationwide population study. The LancetID-D-12-0107 - S1473-3099(12)70341-9
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HIV in the United Kingdom: 2013 Back-calculation estimate of HIV incidence and prevalence of undiagnosed infection among MSM: UK, 2003-2012
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HIV and STI Department, Health Protection Agency - Colindale HIV and AIDS Reporting System Distribution of the infectious population among HIV-infected MSM: UK, 2010
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People living with HIV by diagnostic and treatment status, and number with detectable viral load, UK, 2006-2012
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Phillips et al, HIV Synthesis transmission model of HIV in MSM
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All people: Age, longer term condomless anal sex partner, number of short-term condomless anal sex partners People with HIV: CD4 count, viral load, ART drugs, adherence, resistance, risk of AIDS / death. Phillips et al HIV Synthesis transmission model of HIV in MSM Simulation model - each time the model program is run it creates a ‘dataset’ of the lifetime experiences of a 1 in 10 sample of adult MSM in UK Methods and fit to HIV natural history and effect of ART extensively documented in Phillips et al, PLOS One 2013
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Phillips et al – Plos One 2013 Incidence of HIV per 100 MSM-year, UK
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Model Fit, MSM in the UK
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Counter – factual scenarios, Phillips et al PLOS One 2013 No condom use (a)ART at diagnosis from 2000 (b)Increased testing rates (c)Higher testing and ART at diagnosis (A) (d) NOTE (A)Cessation of all condoms in 2000 would have resulted in a 400% increase in incidence 22
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0 1 2 3 4 5 Proportion Potential increases in testing: probability of diagnosis by time from infection For those infected after 2015 Years from infection base test rate (Current situation) test rate + test rate ++
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Number of new infections per year 2015 2020 2025 2030 Year HIV incidence test rate ++ ART 350 base test rate ART at diagnosis test rate + ART at diagnosis test rate ++ ART at diagnosis test rate + ART at 350 base test rate ART at 350 95% CI given for two lines to illustrate uncertainty over mean effect
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HIV and STI Department, Health Protection Agency - Colindale HIV and AIDS Reporting System Sexual Health Messages for MSM Have an HIV/STI screen at least annually, and every three months if having unprotected sex with new or casual partners. Unprotected sex with casual and new partners who are believed to be of the same HIV status (serosorting) is unsafe. – For HIV positive men, serosorting poses a risk of acquiring other STIs and hepatitis with serious treatment implications. – For HIV negative MSM it carries the risk of HIV transmission (as a quarter of HIV positive MSM are unaware of their infection), as well as acquiring STIs
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HIV and STI Department, Health Protection Agency - Colindale HIV and AIDS Reporting System Predictors of incidence: Getting the evidence Role of primary infection Role of multiple partners Role of ‘regular’ vs ‘casual’ Frequency of testing Impact of ART at diagnosis Impact of PREP Role of PN Role of STIs Role of recreational drugs
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Conclusion Treatment as prevention’ is unlikely to be sufficient to reduce HIV transmission in the UK since it is estimated that two-thirds of HIV positive people with detectable viral loads are unaware of their infection and those in early infection are most likely to transmit their infection Earlier treatment must be combined with a substantial increase in the frequency of HIV testing among groups most affected. Other prevention strategies, condom use, PREP, reduced partners, treatment of STIs, and improvements in sexual well being remain critical in the control of HIV and other STIs epidemic 27
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HIV team at Public Health England Andrew Phillips, UCL All the patients living with HIV as well as clinicians, health advisors, nurses, microbiologists, public health practitioners, data managers and other colleagues who contribute to the surveillance of HIV and STIs in the UK.
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Cowan SA, and Haff J Statens Serum Institut, and the AIDS-foundation, Copenhagen, Denmark Materials and methods Re-analysing self-reported data from the 2009 Sex Life Survey, we changed the criteria for inclusion in the groups US and non-US. If a HIV-positive respondent had UAI with a non-positive partner, and had a high VL, we didn’t change his US-status, but if he had low VL, we changed his status to non-US. For HIV-negative MSM with steady partners we didn’t change the US-status but for HIV-negative MSM who had UAI with casual partners we changed the status to US. Proportions of MSM who had US as seen conventionally, and according to the new paradigm were calculated, and compared to each other, and to the proportion of respondents reporting UAI. Introduction In the context of HIV transmission prevention, risk behaviour or unsafe sex (US) among men who have sex with men (MSM) has conventionally been defined as unprotected anal intercourse (UAI) with a non-concordant partner, i.e. the partners have opposite sero- status, or one or both have unknown sero-status. Recent research has shown that HIV-positive persons who have very low viral load (VL) are practically incapable of transmitting HIV sexually. Thus from an HIV-epidemiological perspective it may no longer be meaningful to assign the label US to UAI when one of the partners is an HIV-positive MSM who has an undetectable VL. Likewise it can be argued that labelling UAI between casual partners, based on self-reported negative HIV-status of the respondent and his partner(s), as non-US, results in a falsely low rate of US. The aim of this study was to explore a new paradigm for the concept of US in the context of HIV-transmission prevention. Results Out of 108 HIV-positive MSM who had UAI with non-positive men, 45, who had undetectable VL, were no longer considered to have had US. Out of 898 HIV-negative MSM, 187 changed from non-US to US because they had UAI with casual partners. The overall proportion who had US changed from 37% to 49%. Among HIV-positive men it changed from 65% to 20%, among HIV-negative it changed from 27% to 48%. Figure 3. Changes in the proportion of US among HIV-negative and HIV-positive MSM after applying a new paradigm for US where HIV-positive MSM with low VL are no longer considered to have US, even if they have UAI with non-positive partners, and HIV-negative MSM are considered to have US if they have UAI with casual partners, even if they believe the casual partner to be HIV-negative too. Contact Susan Cowan: sco@ssi.dk. Table 1. Definitions of when unprotected anal intercourse (UAI) is considered unsafe sex (US) according to the conventional, and the new paradigm, by respondent's and partners' HIV-status and by steady/casual partners. Changes in definition are marked in purple *) In theory it would be Non-US in case the HIV-positive partner had low VL, but this was not reported in the survey **) In theory it would be NON-US in case the casual partner disclosed positive HIV-status Presented at AIDS 2014 – Melbourne, Australia Conclusions The new paradigm dramatically changes the prevalence and distribution of US. A larger proportion of MSM who have US is found among HIV-negative MSM than among HIV-positive MSM, even though HIV-positive report more UAI. The new paradigm helps explain how HIV-incidences keep rising despite the preventive effect of treatment: HIV-negative MSM have UAI with undiagnosed HIV-positive MSM who consider themselves negative. This is conventionally not considered as US, although transmission potentially occurs. In contrast, UAI with diagnosed, treated HIV-positive MSM with low VL doesn’t involve a transmission risk, and should therefor not be considered as unsafe sex in relation to HIV-transmission. Behavioral surveys that use the term Unsafe Sex should take this new paradigm into account when calculating rates among HIV- negative and HIV-positive MSM.
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