Sexual practices, sexual behavior and HIV risk profile of key populations in Nigeria

Key populations –people who inject drugs (PWID), men who have sex with men (MSM) and female sex workers (FSW) – have higher vulnerability to HIV infection than the general population. The prevalence of HIV infection among PWID is 28 times higher than that of the general population; while the prevalence of HIV among MSM and FSW is estimated to be 19 and 12 times higher than that of the general population respectively, in low- and middle-income countries [1]. The HIV prevention and treatment needs of key populations have however, been inadequately addressed by the national HIV and AIDS responses in most low- and middle-income countries (LMICs), particularly in sub-Saharan Africa countries [2] one of which is Nigeria.

The HIV response needs of key populations in Nigeria is completely donor driven [3]. Yet the HIV response is critical to the success of achieving epidemic control in Nigeria because the HIV epidemic among key populations is a key driver of the national epidemic – there is a concentrated epidemic among key populations and another epidemic among the general population [4]. Strategic but distinct interventions are needed to reduce the HIV incidence in the general and key populations. The epidemic among the general population is largely driven by unprotected heterosexual intercourse and mother to child transmission of HIV infection [5]. It is speculated that the driver of the epidemic among key populations is unprotected sexual intercourse and untreated sexually transmitted infections [5]. The evidence for the driver of the HIV epidemic among key populations is largely anecdotal.

Strategic interventions were designed for key populations based on these anecdotal evidences. These proposed interventions are documented in key national documents such as the National HIV Strategic Plan [6] and the National HIV Prevention Plan [5]. Specific national guidelines for programming with FSW [7] and PWID [8] were also developed. To facilitate programming, a local epidemiological appraisal was conducted to estimate the size of FSW, MSM and PWID, and map ‘hot spots’ where key populations’ converge in large numbers [9]. Other specific interventions include the design and implementation of one stop-shops to provide services across the prevention-testing-treatment-care cascade for key populations in Nigeria [10]. The HIV prevention packages for MSM, FSW and PWID provide frequent access to HIV testing, condom access (including lubricants for MSM) and access to treatment of sexually transmitted infections. There is no harm-reduction program for PWID [5].

Despite these efforts, the HIV prevalence among the key populations remains higher than that of the general population. Compared to the national prevalence of 3.1% [11], the HIV prevalence is 3.4% for PWID, 19.4% for brothel based female sex workers, 8.6% for non-brothel based female sex workers, and 22.9% for MSM [12]. Key populations and their sexual partners are estimated to account for about 40% of new HIV infections in Nigeria, although they constitute only 3.4% of the national population [13].

Despite the significant contribution of key populations to the HIV epidemic in Nigeria, there is very little evidence-based information on the drivers of HIV infections for FSW, PWID and MSM in Nigeria. FSW, PWID and MSM are often managed as a homogenous group with an assumption that their HIV sexual risk profile is similar. The absence of evidence to suggest differences in the HIV sexual risk profile of FSW, PWID and MSM makes it difficult to develop specific programs that may reduce the HIV risk of each group. When evidence is provided, the contents of education programs can be developed, which should help individuals to improve their perception of threat and increase the likelihood for behavior change [14]. Behavior change happens when there is a raised consciousness of threat from HIV infection, the individual substitutes risk behaviors with alternative behaviors, reinforces the new positive behavior due to the rewards received, and remove cues that reinforce the negative behavior [15].

The objective of this study was to determine and compare the sexual behavior and HIV sexual risk profiles of FSW, MSM and PWID; and identify factors associated with recent condom use among the groups, with the aim of providing evidence to strengthen HIV interventions for FSW, MSM and PWID in Nigeria.

The questionnaires retrieved from 488 respondents were analysed – response rate of 97.6%. The study population consisted of 188 (38.5%) FSW, 145 (29.7%) MSM and 155 (31.8%) PWID. Six (1.2%) respondents were transgender (Table 1). The key populations groups differed significantly in their marital status: FSW had higher proportion of divorced, widowed and separated persons but less proportion of those who were never married when compared with MSM and PWID (p < 0.001).

A high proportion of FSW, MSM and PWID engage in high risk behaviors: they practiced unprotected anal sex; and will not use condom if their partner refuses to use condom; MSM and PWID were less likely to have used condom when compared to FSW; and a lower proportion of FSW and PWID used condom during anal sex when compared with MSM. The proportion of MSM and FSW who use psychoactive drugs and who inject drugs was also high. The use of psychoactive substance and the ability to negotiate condom use were associated with consistent use of condom use in the last 30 days of the survey. Finally, we found that PWID had the highest HIV risk behavior: they were less likely to use condom during sexual intercourse and refuse sex with partners who refused to use condoms when compared with FSW and MSM; and more than a third of the population share needles and syringes.

One of the strength of this study was the engagement of focal persons from each of the key populations with the data collection process. Although they are formally less qualified than the research staff and field workers, the focal persons had extensive experience and understanding of the nuances of their communities [24, 25], which proved valuable in planning and implementing the study. Their engagement enhanced access and responsiveness of peers to the survey questions, strengthened consent and information processes since potential participants felt freer to ask questions [24], and increases the authenticity of the data generated for this study. Their involvement also increased the ability to recruit from different sub-groups of key populations. The extensive training provided to the focal persons on data collection using ethically appropriate methods and techniques, enhanced the value added to the research process. A second strength of the research methodology was the recruitment of study participants through four waves of snowballing. This enhanced the diversity of the study participants thereby addressing possible concerns about the representativeness of the sample [26].

The study however had some limitations. The cross-sectional approach limits the study to only establishing associations as no cause-inferential deductions can be made. Also, participants had to recall information on condom use which introduces recall bias. It is also possible that subgroups of the study population not represented by the seeds recruited for the study, may have been inadvertently left out in the recruitment process. Individuals who are hiding due to legal and policy restrictions - FSW, MSM and PWID are criminalized in Nigeria –may also have been left out during the recruitment [27].

We, acknowledge that the use of audio computer assisted self-administered instruments (ACASI) may have improved the reporting on some high-risk behavior. Adebajo et al. [28] had reported improved reporting of high-risk behavior by MSM and PWID in Nigeria with the use of ACASI. In the absence of ACASI, the engagement of peers as community recruiters was the next best option we had and used. The engagement of the focal persons in studies involving key populations in environments with high level of stigma against them like Nigeria, is invaluable irrespective of the use of ACASI.

The study findings provide valuable evidence on peculiar sexual and reproductive health needs of FSW, MSM and PWID in Nigeria. Although a number of studies conducted in Nigeria have examined the sexual pattern and or HIV risk profile of MSM [29‐31], FSW [32, 33] and PWID [28], including the bisexual profile of MSM in Nigeria [34], studies comparing findings on sexual and reproductive health of the populations are rarely reported. We are not aware of any study conducted in Nigeria on the study topic prior to our study.

One of the key findings was that PWID had more risk behaviors for HIV infection than MSM and FSW. Ironically, the national HIV prevalence for key populations in Nigeria is lowest for PWID: less than half the prevalence for MSM and FSW; and close to the HIV prevalence for the general population [12]. The reason for this is not clear. Past studies had attributed the low prevalence of HIV infection among PWID to low prevalence of needle sharing [35], but the outcome of this study does not suggest that the prevalence of needle sharing is low. The high vulnerability of PWID to HIV infection identified in this study, and the actual national HIV prevalence figures for PWID suggests that HIV prevention efforts targeting PWID need to be considerably strengthened to keep the HIV prevalence in the community low. Stigma associated with drug use and the criminalization of injecting drug use hinder PWID from access HIV prevention services [36]. Unfortunately, stigmatization and criminalization of drug use are still major problems in Nigeria [37] and may likely detract PWID from accessing HIV prevention services. Currently, the Nigeria HIV prevention programs for PWID do not include needle and syringe exchange and other harm reduction interventions. HIV prevention interventions for PWID also need to include access to treatment for substance abuse since those treated for substance abuse are more likely to adopt safer behaviors [36].

Unlike Lancaster et al. [38], who demonstrated that use of psychoactive substances is significantly associated with lower use of condom during sexual intercourse, we found that users of psychoactive substances were more likely to have used condom in the last 30 days of the survey. The use of psychoactive substances is expected to increase the risk for HIV infection [39]. We assume this finding may not be unconnected to the intense HIV education provided to drug users in the states were the study was conducted. The finding may suggest that the investment of GFATM funds for education of key populations may be having impsct. The finding however need further investigations.

We found that a significant proportion of FSW and PWID practice anal sex. Previous studies conducted in Nigeria had also highlighted that anal sex is practiced between heterosexuals [40‐42]. Unfortunately, education about the risk of contracting HIV through anal sex has been limited to the HIV education curriculum of MSM, and may explain the observed higher use of condom for anal among MSM when compared with FSW and PWID. This study finding highlights the need for the national HIV response program to broaden the HIV preventive education to include anal sex education for FSW and PWID.

Psychoactive substance use prevention education and interventions also need to be targeted at MSM and FSW. Prior studies had indicated that a significant number of MSM and FSW inject drugs [38, 43]. This finding further highlights the challenges associated with the design and implementation of siloed programs that may be ineffective in reaching out to populations that have multiple cross-silo-cutting HIV risk behaviors [44]. Our study however did not explore the proportion of MSM and PWID who sell sex. The exchange of sex for money by female PWID was identified as the major driver of the high prevalence of HIV among female PWID [5], and the justification for focusing on sexual prevention of HIV for PWID [5]. Future studies on sexual and reproductive health of key populations in Nigeria could explore transaction sex as a possible third intersect in the HIV risk profile of key populations.

The low proportion of MSM and FSW who use condom consistently in this study; and the global decrease in condom use [45] remains a challenge for HIV prevention among key populations. The continued challenge with use of condom in this study population makes it imperative to explore the use of pre-exposure prophylaxis (PrEP) for key populations who engage in condomless sex. Thus, when screening for persons who should be eligible for PrEP access, the inability to negotiate condom use and the use of psychoactive substance should be an eligibility criteria for MSM, FSW and PWID. Though a national policy on the use of PrEP identified persons at substantial risk of HIV infection eligible for PrEP access [46], and a PrEP demonstration study was conducted with sero-discordant couples in Nigeria [47], there is currently no roadmap drawn on how PrEP can be accessed in Nigeria. With the available evidence on the efficacy of PrEP for those at substantial risk for HIV infection [48], it is an ethical imperative and a human rights requirement that PrEP be made accessible to key populations in Nigeria in view of their HIV risk profile.

Our study findings indicate that the sexual risk behavior and HIV risk profile of FSW, MSM and PWID are not clearly distinct. There are commonalties in HIV infection risk behaviors amongst the populations – inconsistent condom use during sex, use of psychoactive substances and injecting drug use. The cross-silo-cutting HIV risk behavior we have demonstrated in this study indicates however, that programmatic interventions for the groups cannot be limited to a specific group; interventions to reduce risk of sexual transmission of HIV, and transmission of HIV infection through sharing of needle and syringes are applicable to MSM, FSW and PWID. Future studies need to explore the prevalence of transactional sex among MSM and PWID.