Petra De Koker (UCT/Ugent) PREPARE CONSORTIUM MEETING BERGEN, NORWAY 6-8 OCTOBER 2010

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1 Petra De Koker (UCT/Ugent) PREPARE CONSORTIUM MEETING BERGEN, NORWAY 6-8 OCTOBER 2010

2 HIV and Herpes Simplex Virus (HSV) 1 & 2 HIV prevalence SA Adolescents (15-19y): M (2.5%), F (6.7%) Adults (15-49y): 18.1% [15.4% %] (UNAIDS, 2010) HSV-1 & HSV-2 in SA Prevalence/incidence? Amongst the commonest human viral infections Many infected individuals are asymptomatic HSV-2 Occurs with the onset of sexual activity Prevalence increases with age (Johnson Ret al., 1989) Associated with early first intercourse, having many sexual partners (Stavraky et al., 1983; Koutsky et al., 1990) = surrogate marker for HIV-1 (Benjamin et al., 2008)

3 Importance for adolescents Sexually active adol at increased risk for many STDs (incl HIV & HSV- 2) (Cowan & Mindel, 1993) Preventing STDs/STIs => reduce HIV-1 transmission (de Jong et al., 2010) Vulnerability depends on e.g. Experiments (also substance abuse), age at sex debut, physical & psychological maturity Systematic review & meta-analysis of LT studies, to estimate the sexspecific effect of HSV-2 on the acquisition of HIV infection (Freeman et al., 2006) 19 studies; 18 adjusted for age & at least one measure of sexual behaviour => HSV-2 infection associated with a three-fold increased risk of HIV acquisition

4 Evidence-based research in Zimbabwe & Uganda Brown et al., 2007 (Zim & Ug) A prospective cohort study among 4531 sexually active, HIV neg F (18 35y) To estimate the effects of prevalent & incident HSV-2 infection on HIV acquisition HSV-2 and HIV serostatus evaluated at enrollment & quarterly for months HSV-2 seroprevalence at enrollment: 52% (Ug), 53% (Zim) => Needed to curb the spread of HIV: implement known HSV-2 control measures => HSV-2 plays an important role in the acquisition of HIV among women

5 Evidence-based research in South Africa (SA) descriptive study Auvert et al., 2001 (SA) Community-based, cross-sectional study among M (N=723) & F (N=784) (14-24 y). Questionnaires and biological tests HIV prevalence: M: 9.4%; F: 34.4% HSV-2 prevalence: M: 17.0%; F: 53.3% => HIV infection among F increases rapidly after the onset of sexual activity & reaches extremely high levels by 24 y => HSV-2 plays a major role in the spread of HIV

6 Evidence-based research in SAintervention studies Ross et al., 2007 (Tanzania) Multicomponent intervention programme on the sexual health of adol (14-19y) => Some impact of the school, clinic & community-based intervention on knowledge, attitudes & sexual behaviour, particularly among young men, but no impact of the intervention on biological outcomes (incl HIV, HSV-2) or pregnancy Cowan et al., 2008 (Zimbabwe); Cowan et al., Multicomponent community-based intervention delivered to inschool & out-of-school youth (9 th y of schooling), parents and clinic staff - 4 y intervention => Impact of the intervention on knowledge, self efficacy & attitudes, pregnancy but had no effect on HIV and HSV-2

7 Evidence-based research in SAintervention studies (cont.) Jewkes et al., 2008 (SA) RCT to assess the impact of Stepping Stones, a HIV prevention programme, on incidence of HIV & HSV-2 & sexual behavior 1360 M & 1416 F aged year Tested at baseline, after 12 & 24mnths => No evidence that Stepping Stones lowered HIV incidence => Reduction of about33% in the incidence of HSV-2 => Sign improved reported risk behaviours in M, with a lower proportion of M reporting perpetration of IPV => HSV-2 & IPV are risk factors for HIV

8 Evidence-based research in SAintervention studies (cont.) Pronyk et al., 2006 (SA) RCT intervention with Microfinance for AIDS and Gender Equity (IMAGE) study to assess a structural intervention that combined a microfinance programme with a gender and HIV training curriculum year-old household co-residents => Experience of IPV reduced by 55% => No affect on the rate of unprotected sexual intercourse with a non-spousal partner => No effect on HIV incidence => A combined microfinance and training intervention can lead to reductions in levels of IPV

9 Conclusions Adolescents = important target group Evidence-based research Several age groups (range: 14-35y) Intervention studies: effect sex behaviour, knowledge & attitudes; effect on biological markers varies; effect on IPV. HIV HSV-2 (acquisition and transmission)

10 Questions regarding PREPARE Use HSV-2 as marker for sexual debut? Test adolescents for HSV-2? Test adolescents for other STIs?

11 References UNAIDS. South Africa Progress Report. March Johnson RE, Nahmius AJ, Magder MPH, Lee FK, Brooks CA, Snowden CB. A seroepidemiologic survey of the prevalence of Herpes simplex virus type 2 infection in the United States. NEnglJ Med 1989;321:7-12. Stavraky KM, Rawls WE, Chiavetta J, Donner AP, Wanklin JM. Sexual and socioeconomic factors affecting the risk of past infections with herpes simplex virus type 2. Am_J Epidemiol 1983;118: Koutsky LA, Ashley RL, Holmes KK, et al. The frequency of unrecognised Type 2 Herpes simplex virus infection among women. Sex Transm Dis 1990; 17:90-4. Benjamin RJ, Busch MP, Fang CT, Notari EP, Puren A, Schoub BD, Tobler LH, Hogrefe W, Heyns A du P, Stramer SL, and Crookes RL. Human immunodeficiency virus-1 infection correlates strongly with herpes simplex virus-2 (genital herpes) seropositivity in South African and United States blood donations. Transfusion, Volume 48, February 2008, Cowan MF, Mindel A. Sexually transmitted diseases in children: adolescents. Genitourin Med 1993;69:

12 References (cont.) Marein A. W. P. de Jong, Lot de Witte, Maureen E. Taylor, and Teunis B. H. Geijtenbeek. Herpes Simplex Virus Type 2 Enhances HIV-1 Susceptibility by Affecting Langerhans Cell Function. The Journal of Immunology, 2010, 185: Freeman EE, Weiss HA, Glynn JR, Cross PL, Whitwortha JA, and Hayes RJ. Herpes simplex virus 2 infection increases HIV acquisition in men and women: systematic review and meta-analysis of longitudinal studies. AIDS 2006, 20: Brown JM, Wald A, Hubbard A, Rungruengthanakit K, Chipato T, Rugpao S, Mmiro F, Celentano DD, Salata RS, Morrison CS, Richardson BA and Padian NS. Incident and prevalent herpes simplex virus type 2 infection increases risk of HIV acquisition among women in Uganda and Zimbabwe. AIDS 2007, 21: Auvert Ballard R, Campbell C, CaraeÈl M, Carton M, Fehler G, Gouws E, MacPhail C, Taljaard D, Van Dam J and Williams B. HIV infection among youth in a South African mining town is associated with herpes simplex virus-2 seropositivity and sexual behavior. AIDS 2001, 15: Ross DA, Chnagalucha J, Obasi A, et al. Biological and behavioural impact of an adolescent sexual health intervention in Tanzania: a community-randomized trial. AIDS 2007; 21:

13 References (cont.) Cowan FM, Pascoe SJ, Langhaug LF, et al. The Regai Dzive Shiri project: a cluster randomized controlled trial to determine the effectiveness of a multicomponent community based HIV prevention intervention for rural youth in Zimbabwe: study design and baseline results. Trop Med Int Health 2008; 13: Cowan FM, Pascoe SJ, Langhaug LF, et al. The Regai Dzive Shiri project: the results of a cluster randomised trial of a multicomponent HIV prevention intervention for young people in rural Zimbabwe [abstract]. 15th ICASA Conference. Dakar, Senegal; Jewkes R, M Nduna, J Levin, N Jama, K Dunkle, A Puren, N Duvvury. Impact of Stepping Stones on incidence of HIV and HSV-2 and sexual behaviour in rural South Africa: cluster randomised controlled trial BMJ 2008;337:a506. Pronyk PM, Hargreaves JR, Kim JC, Morison LA, Phetla G, Watts C, Busza J, Porter JD. Effect of a structural intervention for the prevention of intimate-partner violence and HIV in rural South Africa: a cluster randomised trial. Lancet Dec 2;368(9551):