The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique Final Report

Transcription

1 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique Final Report

2 Ministério da Saúde

3 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique Final Report Partners National Institute of Health (INS) The United States Centers for Disease Control and Prevention (CDC) University of California, San Francisco (UCSF) Pathfinder International International Training and Education Center for Health (I-TECH) Improving health and reducing inequities worldw

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5 Acknowledgments The study team (see Appendix 12.1) acknowledges the immense contributions of all who in diverse ways contributed to the successful implementation of The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique The survey team would like to dedicate this report in memory of Neusa de Silva, an invaluable team member of the IBBS-FSW in Mozambique. Disclaimer This research has been supported by the President s Emergency Plan for AIDS Relief (PEPFAR) through the US Department of Health and Human Services and the Centers for Disease Control and Prevention (CDC) Mozambique Country Office under the terms of Cooperative Agreement Number U2GPS The views expressed in this report do not necessarily reflect the views of the US Centers for Disease Control and Prevention or the U.S. Government. Recommended style for citation INS, CDC, UCSF, Pathfinder & I-TECH (2013). Final Report: The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique San Francisco: UCSF. The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

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7 Table of Contents 1. Preface Executive Summary Acronyms Introduction The HIV epidemic in the region The HIV epidemic in Mozambique Epidemiological importance of HIV surveillance among FSWs in Mozambique Description of FSWs in the region Description of FSWs in Mozambique Survey objectives Methodology Respondent-driven sampling (RDS) Survey sites and implementation training Eligibility criteria Sample size Informed consent Behavioral data collection Laboratory procedures Procedures for population size estimation Data management Ethical considerations Results Survey population Socio-demographic characteristics of the FSW population Sexual history and risk behaviors Condom use HIV knowledge Coverage of prevention programs Access and use of health services Violence and sexual assault Consumption of alcohol and drugs Information on STI s Previous HIV testing and risk perception Access to HIV care and treatment HIV Test Results HIV prevalence by demographic characteristics HIV prevalence and reproductive health HIV prevalence and sexual behavior HIV prevalence and access to prevention and health services HIV prevalence among FSWs by violence and alcohol consumption HIV prevalence by HIV testing history, risk perception, and self-report of STI symptoms or diagnosis...55 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

8 Table of Contents 8. FSW Population Size Estimates Unique event multiplier Unique object multiplier Population size estimates based on literature review Stakeholder feedback and consensus Conclusion Key findings Survey limitations Recommendations References Appendices Survey team FSW population size estimation data IBBS-FSW survey questionnaire The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

9 1. Preface It is with great satisfaction that we present the final report of the Integrated Biological and Behavioral Survey among Female Sex Workers in Mozambique (IBBS-FSW 2011, 2012). This is the first representative survey of its kind conducted in Mozambique. This survey estimated the prevalence of HIV and syphilis and associated risk behaviors among FSW, estimated the FSW population size, and assessed the use of and access to health and social welfare programs among FSW to identify means for increasing their coverage and uptake in Mozambique. While the National Survey on Prevalence, Behavioural Risks and Information on HIV and AIDS in Mozambique (INSIDA) provides important information on the HIV epidemic among the general population, there is a need for additional information about key populations at higher risk for HIV. This need is clearly expressed in the National Strategic Plan for HIV and AIDS in Mozambique (Plano Estratégico Nacional de Resposta ao HIV e SIDA de Moçambique - PEN III ), which urges the completion of representative surveys to provide evidence and define specific actions targeting these groups. The World Health Organization has defined populations at higher risk as those that have behaviors that can put them at greater risk of HIV infection including multiple unprotected sexual partnerships, unprotected anal sex with multiple partners, and injecting drugs with non-sterile equipment. PEN III calls for an IBBS to provide HIV prevalence data and associated risk behaviors among FSW, long distance truck drivers, mine workers who work in South African mines, and men who have sex with men. This report represents the results of the IBBS-FSW and is one of four IBBS conducted in among populations at higher risk for HIV in Mozambique. The data from the IBBS-FSW confirm that FSW are a key population at risk for HIV and that within the FSW population older FSW are disproportionately affected and a substantial proportion of FSW did not know they were infected with HIV. We have the opportunity to improve access to HIV care and treatment and to support positive prevention interventions among older FSW, as well as enhance social and behavioral prevention interventions toward younger FSW to prevent the spread of HIV. This IBBS provided a safe environment for FSW-friendly HIV counseling and testing and is an example of the types of services that can be achieved nationally for key populations at higher risk for HIV. Based on this scientific evidence, it is our hope that the Ministry of Health and the National HIV and AIDS Council, together with partners involved in HIV programming, will strive to implement strategic and comprehensive HIV prevention and care programs that will address the unique characteristics and vulnerabilities identified among FSW in Mozambique. This IBBS serves as a baseline for future IBBS rounds of the same design as part of a national biological and behavioral surveillance system that tracks changes in the HIV epidemic and the national response to the epidemic. Future rounds of IBBS-FSW will monitor the progress achieved by targeted interventions for the prevention of HIV infection and provision of care and treatment among FSW. In order to effectively respond to HIV, it is necessary to know your epidemic by gathering important epidemiological data. With this in mind, the National Institute for Health of Mozambique (Instituto Nacional de Saúde INS) welcomes this important epidemiologic contribution and will continue to facilitate a collaborative environment where such important findings can be actionable at the highest level of the national response with the ultimate goal of an AIDS free generation. We thank those who agreed to participate in this survey. The success of the survey was possible due to the commitment and professionalism of the team of survey investigators, community outreach workers, site supervisors, HIV counselors, nurses, interviewers, coupon managers, receptionists, and laboratory technicians. Our thanks are extended to various institutions, including the Centers for Disease Control and Prevention (CDC), the University of California at San Francisco, Pathfinder International, International Training and Education Center for Health (I-TECH), the Provincial Directorates of Health in Sofala and Nampula, Maputo City Directorate of Health, and members of the IBBS Technical Working Group. Ilesh V. Jani, MD, Ph.D Director, National Institute of Health Maputo, November 2012 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

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11 2. Executive Summary The National Strategic Plan for HIV and AIDS in Mozambique (Plano Estratégico Nacional de Resposta ao HIV e SIDA de Moçambique - PEN III) considers female sex workers (FSWs) a priority group for interventions to prevent HIV because of their increased vulnerability to HIV infection. The Integrated Biological and Behavioral Survey (IBBS) among FSWs in Mozambique (IBBS-FSW) was the first to be carried out in the country and sought to determine the prevalence of HIV in the urban areas of Maputo, Beira, and Nampula and the prevalence of syphilis in Maputo, together with their behavioral risk factors. It was also intended to estimate the size and distribution of the FSW population in the three urban areas. Furthermore the survey enabled evaluation of utilization and access to health care programs among FSWs, and assessed the possibility of including syphilis testing at other locations outside of Maputo in future rounds of IBBS-FSW. Survey participants were sampled with a methodology known as respondent driven sampling (RDS), which is widely used for reaching hard to reach populations that are stigmatized or considered at high risk for HIV and sexually transmitted infections (STI s). Women and girls 15 years of age or older who had exchanged sex for money in the six months preceding the survey and who lived, worked or socialized in one of the three urban areas of the survey were eligible to participate. In total 400 eligible FSWs were recruited to participate in the survey in Maputo, 411 in Beira, and 429 in Nampula. The survey was conducted between September 2011 and March This report does not present the findings on syphilis but focuses on HIV and population size estimations. The results of syphilis testing will be published in a separate report. HIV prevalence The prevalence of HIV among FSWs was 31.2% (95% confidence interval CI: %) in Maputo, 23.6% (CI: %) in Beira, and 17.8% (CI: %) in Nampula. The prevalence of HIV among FSWs in each urban area was significantly higher among FSWs aged 25 and over as compared to FSWs aged years: 60.3% (CI: %) versus 14.5% (CI: %) in Maputo, 47.9% (CI: %) versus 17.4% (CI: %) in Beira, and 48.0% (CI: %) versus 8.8% (CI: %) in Nampula, respectively. A substantial proportion of FSWs who are infected with HIV in Maputo, Beira and Nampula did not know their HIV status (48.1%, 79.8%, and 89.6%, respectively). Map of Mozambique with HIV prevalence among FSWs, IBBS-FSW % 23.6% Maputo Beira 17.8% Nampula Demographic characteristics Most of the FSWs in the three survey areas were in the 15-to-24-year-old age group. In Maputo, Beira, and Nampula, 36.5%, 58.8%, and 59.0% FSWs, respectively, were students at the time of the survey. Among FSWs in the three urban areas, most had reached but did not necessarily complete secondary education. Many FSWs, 76.3%, 69.6%, and 83.2% in Maputo, Beira, and Nampula, respectively, had no other work than sex work. A majority of FSWs in the three survey areas (63.8%, 76.5%, and 65.4% in Maputo, Beira, and Nampula, respectively) had never married or cohabitated. Sexual risk behaviors and access to health and prevention services In Maputo 34.9%, in Beira 51.5%, and in Nampula 48.4% of FSWs sold sex for money for the first time between the ages of In addition, 8.5%, 7.9%, and 15.5% of FSWs in Maputo, Beira, and Nampula, respectively, started having sex for money under the age of 15 years. The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

12 2. Executive Summary Condoms were not universally used during sex: 14.2%, 26.6%, and 37.2% of FSWs in Maputo, Beira, and Nampula, respectively, did not use a condom the last time they had sex with a client. As for female condoms, 74.8% of FSWs in Maputo, 63.3% in Beira, and 65.9% in Nampula had heard of female condoms but had never used one. In the month preceding the survey, 27.9% of FSWs in Maputo, 47.0% in Beira, and 26.5% in Nampula had 1-2 clients. Some FSWs had substantially higher numbers of clients: 24.9% of FSWs in Maputo, 10.5% in Beira, and 21.8% in Nampula had seven or more clients in the month preceding the survey. In Maputo, Beira and Nampula, 65.4%, 51.9% and 60.0% of FSW respectively, did not have sex with a stable partner in the month preceding the survey. A stable partner is a partner, such as a boyfriend, husband, or lover that is not regarded as a client. A small proportion of FSWs had sex with more than one stable sexual partner in the last month: 6.8% in Maputo, 17.5% in Beira, and 13.5% in Nampula. 2. Results demonstrate the need to improve programs and interventions that contribute to universal and consistent use of (male or female) condoms, especially in sexual relationships with clients, as consistent condom use is not universal among the FSWs in the three urban areas; 3. The high prevalence of HIV among FSWs in the survey areas and the proportion they make up of the adult female population in each area draws attention to the epidemiological importance of health service planning for FSWs and conducting future IBBS rounds among FSWs in order to monitor progress achieved by prevention and care interventions. In Maputo, Beira, and Nampula, 42.1%, 35.2%, and 38.4%, respectively, of FSWs had sought the assistance of a health professional in the six months preceding the survey. Among FSWs seeking assistance from a health professional in the six months preceding the survey, 3.1%, 11.3%, and 9.4% (Maputo, Beira, and Nampula, respectively) had some difficulty obtaining care. The percentage of FSWs who were not using any birth control at the time of the survey was 44.1% in Maputo, 60.6% in Beira, and 48.9% in Nampula. Population size estimate It is estimated that there are 13,554 FSWs in Maputo (including Matola), 6,802 in Beira, and 6,929 in Nampula. In Maputo this represents 2.0% of the adult female population ages 15-49, in Beira 5.0% of the adult female population, and in Nampula 4.5% of the adult female population. Recommendations 1. HIV prevalence was significantly higher among FSWs aged 25 and older compared to those between the ages of 15 to 24 in the three urban areas. This suggests that prevention programs should prioritize younger FSWs, while treatment programs should focus on older FSWs; 12 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

13 3. Acronyms AIDS ARV ATS AUDIT-C CAPI CDC CI CNBS COW DBS EIA FSW HIV IBBS INE INS INSIDA LDH MISAU/MoH NICD PEPFAR PSI QDS RDS Acquired Immune Deficiency Syndrome Antiretroviral Aconselhamento e Testagem em Saúde/HIV Counseling and Testing Alcohol Use Disorders Identification Test-Consumption Computer Assisted Personal Interview Centers for Disease Control and Prevention of the United States of America Confidence Interval Comité Nacional de Bioética para a Saúde/National Bioethics Committee for Health Agente Comunitário de Sensibilização/Community Outreach Worker Dried Blood Spots Immuno-enzymatic Assays Female Sex Worker Human Immunodeficiency Virus Integrated Biological and Behavioral Survey Instituto Nacional de Estatística/National Statistics Institute Instituto Nacional de Saúde/National Institute of Health Inquérito Nacional de Prevalência, Riscos Comportamentais e Informação sobre o HIV e SIDA em Moçambique/National Survey on Prevalence, Behavioural Risks and Information on HIV and AIDS in Mozambique Liga dos Direitos Humanos/Human Rights League Ministério da Saúde/Ministry of Health National Institute of Communicable Diseases in South Africa U.S. President s Emergency Plan for AIDS Relief Population Services International Questionnaire Development System Respondent Driven Sampling The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

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15 4. Introduction 4.1. The HIV epidemic in the region The HIV epidemic in sub-saharan Africa continues to contribute disproportionately to the global burden of HIVrelated morbidity and mortality. From 2001 to 2011 there was a decline of new HIV infections all over the world. In 39 countries, the incidence of HIV among the adult population showed a decline of 25% from 2001 to Thirty-three of these countries were in sub-saharan Africa, where the majority of new HIV infections occur, with an estimated 1.8 million people infected in 2011 (UNAIDS, 2012). Sub-Saharan Africa contributed with 71% of all new HIV infections among adults and children in Although this represents a reduction in the estimated 2.2 million people in sub-saharan Africa with new HIV infections in 2001, the total number of people living with HIV is still on the rise. In 2011, this number reached 23.5 million in the region, representing 69% of the world total (UNAIDS, 2012). The vast majority of people infected with HIV in sub-saharan Africa are infected by unprotected heterosexual intercourse. Unprotected sex with multiple partners remains the biggest risk factor for HIV in the region (UNAIDS, 2010) The HIV epidemic in Mozambique Mozambique has a generalized HIV epidemic, predominantly based on heterosexual transmission. Although it appears to be stabilizing, Mozambique has the eighth highest HIV prevalence in the world (UNAIDS, 2011, UNAIDS, 2010). The most recent national data show an HIV prevalence of 11.5% in adults aged years in 2009 and substantial regional variation: higher HIV prevalence in the Central and Southern regions and lower HIV prevalence in the north (INE, INS, and ICF Macro, 2010). Among adults age 15-49, HIV prevalence is higher in urban areas (15.9%) compared to rural areas (9.2%). Regionally, HIV prevalence is highest in the Southern region (17.8%), followed by the Central region (12.5%), and then the Northern region (5.6%). The prevalence in adult women in the general population aged is highest in the provinces of Gaza (25.1%), followed by Maputo and Maputo City (20.5% and 20.0%), and Sofala (17.8%). Nampula (5.5%) has the lowest prevalence (INS, INE, and ICF Macro, 2010). In Mozambique, women are disproportionately affected by HIV infection compared to men. HIV prevalence among women is 13.1% compared to 9.2% among men (INS, INE, and ICF Macro, 2010). Among adults aged 15-49, HIV prevalence increases with age, level of education, and wealth. HIV prevalence is highest among women aged years (16.8%) and men aged years (14.2%) (INS, INE, and ICF Macro, 2010) Epidemiological importance of HIV surveillance among FSWs in Mozambique While the majority of transmission in countries with generalized HIV epidemics occurs through unprotected heterosexual sex, certain groups engaging in higher risk behaviors may have higher rates of HIV infection than the general population (Kritmaa, 2011; Johnston, 2010). Sex work is regarded as an important source of new HIV infections in Mozambique, with indirect estimates suggesting that sex workers, their clients and their clients partners contributed with 19% of new HIV infections in Mozambique (CNCS, UNAIDS & GAMET, 2009). Surveillance of HIV and risk behaviors among FSWs allows for monitoring a sub-epidemic that has important implications for the overall control of the general epidemic. In addition, FSWs are a stigmatized group and are harder to reach with care and prevention programs designed for the general population. Continued IBBS-FSW will enable an evaluation of the coverage of these interventions Description of FSWs in the region Sex work in sub-saharan Africa is notable for the variety of contexts in which it occurs. Paid sex in sub-saharan Africa typically happens in bars, stalls, the street, hotels, or the residence of FSWs and is often solicited directly without the use of intermediaries (Scorgie, 2011). The situational analysis of FSWs in sub-saharan Africa is complicated by the lack of a stable and universal definition of sex work, in part due to the high prevalence of transactional sex in the region Description of FSWs in Mozambique There is a paucity of literature related to FSWs in Mozambique. A rapid ethnographic mapping that included FSWs in the Maputo corridor was conducted in The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

16 4. Introduction According to the study, sex work varies in terms of price, social class of FSWs and their clients, and the locations where FSWs are found (bars, hotels, streets, markets, and at least one brothel). The study also identified transactional sex as being more common than paid sex (Wilson et al, 2001). A mapping of street-based FSWs in Maputo in 2006 found an average of 191 FSWs working per day in five areas of the city (Rufino et al, 2006). A 2007 study counting 350 FSWs using convenience sampling in two cities along the transport corridor in Tete estimated 4,415 FSWs worked in the area, equivalent to 9.1% of the female adult population between years of age. Over half of the participants (56%) were Mozambican. Among those sampled in the study, the prevalence of active syphilis was 6.3%, HIV was 49.7%, and herpes simplex virus 2 was 83.1%. The study noted that most FSWs appeared to be occasional in nature. That is, most women had a low number of customers and were not selling sex on a daily basis (DPS Tete and ICRH/ UGhent, 2008) Survey objectives To estimate the prevalence of HIV and associated risk behaviors among FSWs in Beira, Maputo, and Nampula To estimate the population size and distribution of FSWs in Beira, Maputo, and Nampula To identify and assess determinants of access and utilization of health and social welfare programs in Mozambique among FSWs To enhance the national capacity to conduct IBBS for MARPs in Mozambique as a key component of a strengthened second generation national HIV surveillance system To evaluate the possibility of including syphilis testing in future IBBS rounds 16 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

17 5. Methodology 5.1. Respondent-Driven Sampling (RDS) Worldwide FSWs comprise a relatively hidden and stigmatized population making them difficult to reach through conventional population-based survey methods. In response to this challenge, methods were developed to approximate a population-based sample through other systematic and rigorous methodologies. Respondent-driven sampling (RDS) is a variant of chain-referral sampling, and when implemented and analyzed properly, produces data that are representative of the target population. RDS uses theoretical and mathematical techniques from various disciplines (such as social network theory, physics, and statistics). These techniques are used to mitigate the biases generally associated with chain referral methods (Heckathorn, 2002). The principles of RDS are well established in the literature (Heckathorn, 2002). RDS has been effective in recruiting FSWs for surveys conducted in other countries in Africa such as Zanzibar (Malekinejad et al, 2008), Sudan (Abdelrahim, 2010), Somalia (Kriitmaa et al., 2010), Kenya (Kriitmaa, 2011), and Mauritius (Johnston, 2010). RDS begins with the selection of seeds that are known to be members of the target population of the survey and who will be the initial participants. Seeds are not randomly selected. Seeds participate in the survey and after participation are instructed to randomly refer three more female sex workers who are part of their social circle. The FSWs invited to participate in the survey form the first wave of recruitment. After participating, they are instructed to refer three more FSWs to participate in the survey, thus forming the second wave of recruitment. These women in turn are also instructed to refer three FSWs that they know, and so on. Each participant in the survey answers questions about the size of their social network. Network size questions can be found in the survey questionnaire located in Appendix The size of the social network reported by each participant forms the sampling base used during data analysis to produce survey weights in order to derive representative estimates of the FSW population. The number of referrals for each participant is usually restricted to three to recruitment chains progress through various social networks. Referrals are made through invitation via a coupon, see Figure 5.1. Each participant receives a primary incentive for participation in the survey and a secondary incentive for each person they recruit who is eligible and who participates in the survey. Management of referral coupons The referral coupon is essential to link enrolled participants with the people whom they refer to the survey and is required for analysis of RDS data to adjust for network size and homogeneity within social networks. Possession of a valid coupon was an eligibility criterion for this survey (Figure 5.1). Issuance and receipt of coupons were tracked electronically using RDS Coupon Manager (RDSCM, version 3.0) and manually using a log book. Initially, eligible participants received three coupons each. In the case of Maputo, due to the low level of recruitment at the beginning of the survey, it was necessary to increase the Figure 5.1: Survey coupon from the IBBS-FSW, Coupon The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

18 5. Methodology number of coupons issued to five for a few weeks. However, as the survey drew to a close and recruitment targets were achieved, the number of coupons distributed was systematically reduced Survey sites and implementation training Survey sites The survey was conducted in three urban areas: Maputo, Mozambique s capital located in the south; Beira, a port city with the second largest population situated in the province of Sofala in the center of the country; and, Nampula, the third largest city in Mozambique located in the north of the country. Formative research found that these areas contained a high number of FSWs representative of the geographical and cultural diversity of the country. Furthermore, in these urban areas, programs were being developed to provide FSW-friendly STI and HIV services. The peri-urban areas surrounding each city were included in the sample (e.g. the city of Matola was included as part of the Maputo survey). Training of the implementation team Before survey implementation began survey team members took part in a two-week training, including general awareness of FSWs in the world, sub-saharan Africa, and Mozambique; ethical issues in research involving human subjects and RDS; the use of netbooks for data collection; preparation and management of dried blood spots (DBS); and, rapid testing for HIV and syphilis. The training consisted of theoretical presentations and practical simulations of survey procedures. Team members from all three survey sites were trained. The teams included a supervisor, a coupon manager, a receptionist, three interviewers/counselors, a nurse (only for Maputo), and two community outreach workers (COW). The teams were centrally supervised by the study investigators Eligibility criteria Eligibility for the IBBS-FSW included the following criteria: 1. Biologically female 2. Age Received money in exchange for sex from someone other than a main partner in the last six months 4. Possession of a valid referral coupon 5. Lived, worked or socialized in the survey area within the last six months 6. Capable and willing to provide written informed consent to participate Exclusion criteria: 1. Previous participation in the survey (in any of the cities) 2. Inability to provide informed consent (including people under the influence of alcohol or drugs) Nationality and citizenship were not exclusion criteria because formative research indicated that foreigners living in Mozambique form part of the FSW population in the survey areas Sample size Sample size estimates are based on the surveillance objective of detecting major changes in the epidemic over time, i.e. between successive IBBS rounds. In this survey, each site was considered a separate survey with the estimated sample size required to follow changes in each location. The size required for the sample was set at 400 FSWs per site, totaling 1200 FSWs for the three sites. To establish the sample size, a common indicator of prevention was used that would be able to measure behavior change through future rounds of IBBS-FSW: condom use at last sex with a client. A proxy of 68% condom use at last sex with a client was used from a study conducted in a night clinic offering FSW-friendly services in Tete Province (Lafort et al. 2010). The sample size was estimated using R (R Development Core Team, 2010) using the function bsamsize in the Hmisc package (Harrell et al, 2011). The estimation is based on the method of Fleiss, Tytun, and Ury (without the continuity correction) to estimate the sample size to achieve a given power of a two-sided test for the difference in two proportions (Fleiss et al, 1980). Using a statistical power of 80% and assuming a design effect of 2.0, a minimum sample of 256 participants per site was calculated in order to detect a significant change (p <0.05) of 15% in condom use between this survey and future rounds using a chi-square test. The estimate was rounded to 400 to take into account the possibility of a higher design effect. Design effects usually vary between 1.2 to 4.6 in RDS surveys (Lane et al, 2009; Kajubi et al, 2008). 18 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

19 5. Methodology Design Effect Upon completion of the survey, the observed design effect were close to 2.0 based on the condom use variable and summarized in the table below. Estimate of Condom use with Last Client Lower CI Upper CI RDS Sample Size Design Effect (DEFF) Maputo 85.8% 81.0% 90.0% Beira 73.4% 67.6% 79.1% Nampula 62.8% 56.5% 69.4% Note, however, that equilibrium must also be reached (i.e. the point at which the sample composition for the key variable does not change even though the sample size increases before the conclusion of the survey. To check for equilibrium (or crude sample stability) key variables such as age, education level, student status, marital status, neighborhood where the FSW met her last customer, number of customers in the last month were monitored weekly during recruitment. Furthermore, to secure the main objective of estimating the prevalence of HIV, with an acceptable confidence interval, the sample size was calculated for the confidence interval for a single ratio. Using the function n.for.survey in the epicalc package (Chongsuvivatwong, 2012) version R 2.14, it was determined that a sample of 377 would be sufficiently large to ensure an accuracy of 0.07, with a design effect of 2.0, around an estimated HIV prevalence of 50% in a population of 5,000 female sex workers. HIV prevalence estimated at 50% is based on a cross-sectional survey conducted in 2007 among 350 FSWs in Tete Province (DPS Tete& ICRH / UGhent. 2008) Informed consent Survey participants gave written informed consent to participate. After participants were explained and agreed with the objectives and procedures of the survey, in Portuguese or in a local language by the interviewer, the participants were asked to put their initials or thumbprint on the consent document written in Portuguese. The consent process allowed participants to give separate consent for each component of the survey, including: 1. Completion of the questionnaire 2. Rapid HIV test with return of results 3. Preparation of DBS samples (and serum samples in Maputo) to be sent to the National Institute of Health (Instituto Nacional de Saúde - INS) for testing Additionally in Maputo: 4. On-site syphilis testing with same day return of results 5.6. Behavioral data collection Behavioral data were collected using a standardized questionnaire based on models successfully used in other countries and adapted to the Mozambican context. The questionnaire included questions that would contribute to national and international indicators used to monitor the response to the HIV epidemic (e.g., UNGASS indicators). The domains of the questionnaire included demographic data, behaviors potentially related to HIV infection and other STI s, discrimination, and access to and utilization of health services, among others. The questionnaire was developed in English and Portuguese and verified by study investigators fluent in both languages. The questionnaire was tested and reviewed by study investigators and members of the survey team during the formative assessment and training for the implementation of the IBBS-FSW. The questionnaire was programmed electronically using Questionnaire Development System (QDS ) version and administered by interviewers using a netbook. The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

20 5. Methodology Figure 5.7: Flowchart of HIV testing, FSW-IBBS, NEG HIV- 1. HIV Rapid Test Determine POS Unigold NEG Indeterminate POS HIV+ NEG HIV- NEG HIV- 2. HIV Test on DBS samples Vironostika POS Murex NEG Genscreen POS HIV+ POS HIV Laboratory procedures HIV and syphilis testing was performed using tests approved by the Ministry of Health of Mozambique (MoH) and following standardized national testing protocols. In Beira and Nampula, rapid tests for HIV were performed using a finger prick. In Maputo, tests were conducted using 10 ml of venous blood. At the time of finalizing this report syphilis results were not available. Thus, they are not presented in the report, but will be available in a future publication. HIV testing HIV rapid testing was conducted on-site, after pre-test counseling by certified counselors. HIV testing was done using two rapid tests according to the sequential algorithm used in Mozambique (MoH, 2008). Screening was done using Determine HIV-1/2 (Abbott Laboratories, UK): non-reactive results were considered negative, and reactive results were confirmed using the Uni-Gold TM HIV (Trinity Bioetch, Ireland) rapid test. Discordant results were classified as indeterminate. Participants with reactive results on both tests were classified as HIV-positive. All participants were offered counseling after testing which contained specific messages tailored to their test results. Participants with an HIV-positive or indeterminate result were referred to health facilities that had received sensitivity training for providing care to female sex workers in order to receive care and treatment or a definitive diagnosis. Dried blood spots (DBS) were collected on two filter papers for centralized HIV testing from each participant that provided informed consent. The results of these tests were anonymous and used solely for surveillance purposes. DBS samples were stored at room temperature at the survey site in waterproof containers with desiccants and humidity indicators and sent weekly to the INS Serology Laboratory where they were stored in a -20 c freezer. HIV testing at the national laboratory was conducted on samples anonymously linked to participant s behavioral data by means of an alfanumeric code. The algorithm used for testing consisted of three enzyme immunoassays (EIA) which detect anti-hiv antibodies. The same algorithm was used during the INSIDA survey in 2009 (INS, NSA, ICF Macro, 2010). Screening was done with Vironostika HIV Uniform II plus O (biomérieux SA, France). Reactive samples and 5% of negative samples were confirmed with Murex HIV 1.2.O (Murex Biotech Ltd, UK). Discrepant results were retested using Genscreen HIV 1/2 Version 2 (Bio-Rad, France). The HIV prevalence estimates presented in this report are based on this surveillance testing algorithm. 20 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

21 5. Methodology All samples were tested using internal quality controls run with all assays during DBS testing. In addition, for external quality assurance 2% of negative samples and 5% of positive samples were randomly selected and sent to an external reference laboratory, the National Institute for Communicable Diseases (NICD) in South Africa Procedures for population size estimation FSWs in Mozambique are considered a hard-to-reach or hidden population. Currently no gold standard exists to determine the true size of the FSW population in Mozambique. Reliable estimates of FSW population size are required for advocacy, resource allocation, planning the provision of appropriate services, and program evaluation. In the FSW-IBBS, three methods were used to estimate the FSW population size in Maputo, Beira, and Nampula. These methods included two multipliers (unique event multiplier and unique object multiplier) and an estimate based on literature (or document analysis). After obtaining FSW population size estimates for each method in each location a consensus meeting was held to present the findings to key stakeholders. Stakeholders evaluated the estimates presented and chose a consensus estimate with upper and lower plausibility bounds (the highest and lowest reasonable estimate). Multiplier methods Multiplier methods used two basic sources of target population data (UCSF & UNAIDS, 2010). The first source was an unduplicated count that included the number of FSWs who attended a specific event or received an object before the launch of the survey. The second source involved the inclusion of some specific questions within the IBBS questionnaire. The specific questions asked if the FSW had participated in the event and/ or received an object (for example, did you participate in an event which took place in XX location on date XX? ). In the IBBS-FSW, the survey participants responded to specific questions related to each of the multipliers to estimate population size. Using these two data sources, the multiplier method provides a population size estimate using the formula: N = n / p. N is the size of the population, n is the number of FSWs counted, and p is the percentage of FSWs who claimed to have participated in a unique event and/or received a unique object. Method 1: Unique object multiplier The unique object multiplier procedures comprised two basic steps: 1. Distribution of a purse made from palm fronds and covered with local fabric called capulana. For each of the three urban areas a different capulana was selected. The purses were distributed to FSWs in the geographical areas of the survey. The distribution was carried out by community outreach workers. 2. Questions were included in the IBBS-FSW questionnaire about whether the participants had received a purse. Method 2: Unique event multiplier 1. The unique event involved holding a party for FSWs prior to the launch of the IBBS-FSW. The party was organized in locations suggested by the COWs and identified as being easy to reach. Music and food were organized for the party, as well as beauty kits, and a dance show. The aim of the event was to record the number of FSWs who attended the event. 2. Questions were included in the IBBS-FSW questionnaire with the purpose of determining whether the survey participants had attended the event. Method 3: Literature review Scientific literature was consulted to gather estimates of the percentage of adult women engaging in sex work in the country and the region Data management Data entry During the questionnaire administration, data were entered directly by the interviewer on a netbook using QDS software. Coupon distribution data were entered by the coupon manager using RDSCM software. The results of on-site rapid tests were entered by the supervisor on a weekly basis using EpiData version 3.1 (EpiData Association, The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

22 5. Methodology Odense Denmark). The supervisor copied all QDS, RDSCM and EpiData files from the individual netbooks onto an on-site password protected computer and ed the encrypted files to the project Data Manager in Maputo each day. HIV results from the INS laboratory were entered into the Census and Survey Processing System (CSPro). Data analysis All survey data were captured using four different databases. The behavioral questionnaire was entered into a QDS database, rapid test results were recorded in an EpiData database, each participant coupon was registered in an RDSCM database, and the HIV test results from the INS laboratory were entered into a Census and Survey Processing System (CSPro) database. The different databases were merged, checked, and cleaned using R version 2.15 (R Development Core Team, 2011). Clean and recoded data from R were exported for data analysis using the RDS Analysis Tool (RDSAT) (Version 6.0, software. RDSAT version 6.0 uses the RDS-II estimator (Volz and Heckathorn, 2008). RDSAT software was used to produce specific population proportions and prevalence estimates with 95% confidence intervals. In RDSAT the number of re-samples for bootstrap was set to 15,000 and the algorithm type as enhanced data-smoothing. Network size was determined by the following questions: Approximately how many other women who have sex for money do you think live in and around <Study area: Maputo, Beira or Nampula>?, Of these, how many do you know by name and they know yours?. Of these, how many can you contact in the next month?, and Of these, about how many of them would you say are 15 years of age or older?. The answer to the last question was used as the network size question. RDSAT also produced survey weights. The data and RDSAT survey weights were exported back to the R 2.15 statistical package for bivariate analysis using logistic regression (svyglm function) to determine individual associations between HIV prevalence and demographic and risk behavior variables. P-values from Wald tests are reported. P-values less than 0.05 were considered statistically significant and those between 0.05 and 0.10 as marginally significant. The recruitment network figures were developed using NetDraw (Borgatti, 2002) Ethical considerations All recommended ethical considerations were taken to protect participants, as they belong to a socially marginalized group and the survey included questions about HIV. The survey was approved by the National Bioethics Committee for Health (CNBS) in Mozambique, the Committee on Human Research (CHR) at the University of California, San Francisco (UCSF) and the Center for Global Health (CGH) at CDC as a research activity involving human subjects but in which CDC involvement does not constitute engagement in human subject research. All data collection staff completed training on human subjects research and signed a confidentiality agreement before commencing survey duties. Any adverse event was reported to both committees using a formal report. Participation in the survey required written informed consent. To protect the identity of participants they were not requested to show an identification document. For participants who consented to rapid HIV testing, pre- and post-test counseling was given by certified counselors, and all of the participants with positive results were referred to a local health facility. In Maputo, all participants with a positive result for syphilis were offered treatment at the survey site. Participant anonymity and data confidentiality were protected in the collection, transmission and processing of data by using unique numeric and alpha-numeric codes that were not derived from any personal identifying information. As is routine in RDS surveys, participants received primary incentives (health and beauty kit) for their participation in the survey and secondary incentives (phone credit) for referral of their peers who were eligible and participated in the survey. The participants were also reimbursed for transportation costs. The amount of reimbursement for the transportation and package of incentives were modest enough so as to not encourage participation of people outside the target population. 22 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

23 6. Results 6.1. Survey population Recruitment summary Recruitment took 26 weeks in Maputo, 18 weeks in Beira, and 17 weeks in Nampula. Seven seeds were selected in Maputo, six in Beira, and five in Nampula. Of the seven selected seeds in Maputo, three produced recruitment chains that contained more than five participants. The longest chain consisted of 313 participants or 78.2% of the total sample of participants in Maputo. The maximum number of waves of recruitment in Maputo was 14. This means a seed was able to recruit at least one person who formed the 1st wave, who in turn recruited at least one person who formed the 2nd wave, who then recruited at least one other person and so on until the 14th wave. Of the six selected seeds in Beira, five produced recruitment chains. The longest chain consisted of 209 participants or 50.9% of the total sample of participants in Beira. The maximum number of waves of recruitment in Beira was 19. All five selected seeds in Nampula produced recruitment chains. The longest chain consisted of 191 participants or 44.5% of the total sample of participants in Nampula. The maximum number of waves of recruitment in Nampula was 19. The three diagrams in Figure 6.1.A illustrate the recruitment chains for Maputo, Beira, and Nampula. The seeds are represented by large squares with arrows that always point outwards. Yellow squares represent participants aged years and red squares participants aged 25 years and older. In Maputo, it may be observed that of the six seeds only two were years old. The age of participants diversified throughout the recruitment process, i.e. participants 25 years old and older recruited not only participants in the same age group but also those years old and vice versa. This demonstrates that despite the fact that the seeds were not selected at random, the sample turned out to be random. The same age diversification was also evident in Beira and Nampula. Table 6.1: Summary of recruitment with RDS in IBBS-FSW, # of seeds # of participants per chain % of participants per chain Max # of waves per chain Median # of waves Max # of waves Study duration (in weeks) Maputo % % % % % & % 0 Beira % % % % % % 0 Nampula % % % % % 2 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

24 6. Results Figure 6.1.A: RDS recruitment network in three urban areas, IBBS-FSW, Maputo Legend Seeds in age group Participants in age group Seeds in age group 25 and up Participants in age group 25 and up Beira Nampula 24 The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique

25 6. Results Summary of eligibility and survey enrollment A total of 2,160, 1,455, and 1,446 coupons were distributed in Maputo, Beira, and Nampula, respectively. Of these distributed coupons, 432, 485, and 482 coupons in each city returned to the survey site with FSWs who had received the coupon from a peer, corresponding to a coupon return rate of 20% in Maputo, 33% in Beira, and 33% in Nampula. All FSWs who arrived at the survey site with a valid coupon were screened for eligibility. Of these, 32 were not eligible in Maputo, 74 were not eligible in Beira, and 53 were not eligible in Nampula. The majority were not eligible because they had not had sex for money in the last six months preceding the survey. Other main reasons for not being eligible were being under 15 years of age and having refused to give informed consent. There were three cases (one in Beira and two in Nampula) in which participants completed all survey procedures but interviewers failed to save the questionnaire data. The study investigators made the decision to exclude these three participants due to lack of data, they were the last in their reference chains, and did not recruit other participants. The final sample size was 400 in Maputo, 411 in Beira, and 429 in Nampula. HIV test results for two participants in Maputo and one in Beira were not available because these participants did not consent to having a DBS prepared. The HIV test done on DBS in the National Laboratory is the result presented in the survey. Not all participants opted to have an on-site rapid test done; there were 55 refusals in Maputo, 115 in Beira, and 130 in Nampula. The main reasons given for refusing testing were that they already knew they were HIV-positive and/or were receiving treatment, they had already been tested recently, or were afraid to know the outcome. Figure 6.1.B: Recruitment flow diagram, IBBS-FSW, Maputo Beira Nampula Coupons Distributed n= 2160 Coupons Distributed n= 1455 Coupons Distributed n= 1446 Screened for Eligibility n= 432 (Coupon return rate: 20%) Screened for Eligibility n= 485 (Coupon return rate: 33%) Screened for Eligibility n= 482 (Coupon return rate: 33%) Not Eligible, n= 32 2 Previously participated 2 Did not consent 3 Did not have sex in past 6 months 24 Did not have set for $ in past 6 months Not Eligible, n= 74 4 Under 15 years of age 1 Did not consent 2 Did not have sex in past 6 months 66 Did not have sex for $ in past 6 months 1 Lost questionnaire and no recruitment Not Eligible, n= 53 4 Under 15 years of age 9 Did not consent 4 Did not have sex in past 6 months 34 Did not have sex for $ in past 6 months 2 Lost questionnaire and no recruitment Enrolled n= 400 (Eligibility rate: 93%) Enrolled n= 411 (Eligibility rate: 85%) Enrolled n= 429 (Eligibility rate: 89%) Refused to provide a DBS, n=2 (Rate of consent for DBS 99.5%) Refused to have an HIV rapid test, n=55 (HIV rapid test consent rate: 86%) Refused to provide a DBS, n=1 (Rate of consent for DBS 99.8%) Refused to have an HIV rapid test, n=115 (HIV rapid test consent rate: 72%) Refused to provide a DBS, n=0 (Rate of consent for DBS 100%) Refused to have an HIV rapid test, n=130 (HIV rapid test consent rate: 70%) The Integrated Biological and Behavioral Survey among Female Sex Workers, Mozambique