The HIV/AIDS Context in Kenya

As of 2007, 1.42 million Kenyans were living with HIV/AIDS, translating to an HIV prevalence of 7.1% [5]. Overall in Kenya, urban residents have a significantly higher risk of HIV infection (7.2%) than rural residents (6.0%) [6]. However, even in urban areas there are huge disparities in HIV prevalence with urban slum settlements having a significantly higher prevalence of HIV than non-slum urban areas. For example, a recent study conducted in two urban slum settlements in Nairobi [7] showed that the overall HIV prevalence in these slum settlements is estimated at 12%, which is much higher than the national average (7.1%) and the overall prevalence in Nairobi (7.0%) [6].

HIV/AIDS among Kenyan Youth

Data from the 2007 Kenya AIDS Indicator Survey show a dramatic difference in HIV prevalence between 15-19 year olds (2.3%) and 20-24 year olds (5.2%) [5]. This difference suggests that many young people are infected during adolescence. Female youth are significantly more likely to be infected than their male peers [5]. For instance, among 15-19 years olds, 3.5% of females and 1% males are HIV positive, while among 20-24 year olds, 7.4% and 1.9%, respectively, are infected [5].

HIV Counseling and Testing (HCT) in Kenya

HCT is an important component of government efforts to address HIV/AIDS in Kenya. Substantial efforts have been made by the Kenyan government and international development partners to increase access to voluntary counseling and testing (VCT) services in Kenya. Through these efforts, the number of VCT facilities, nationally, has increased significantly. For example, between 2000 and 2005, the number of testing facilities increased from 3 to over 500 [8]. Correspondingly, annual service uptake increased from 1000 to 380,000 people during this period [8]. Further, one of the objectives of the Government of Kenya's 2005-2015 Plan of Action under the Adolescent Reproductive Health Development Policy [9] is to establish and promote adolescent-friendly VCT services in order to improve access to and utilization of sustainable youth-friendly sexual and reproductive health services. Although the VCT to population ratio is highest for Nairobi (around one site for every 25,000 people) [8], few studies are available on access to HIV testing services in urban slum settlements in Nairobi, and sub-Saharan Africa, in general.

The 2008-9 Kenya Demographic and Health Survey (KDHS) [6] estimates show a substantial increase in the proportion of youth aged 15-24 years who have ever been tested for HIV and knew their HIV test results compared to 2003 KDHS [10] estimates. The proportions of youth reporting an HIV test during both surveys are illustrated in Figure 1. Overall, although these estimates reflect a significant improvement in the coverage of HIV counseling and testing, these numbers still fall short of the government's 2010 goal of 80% coverage [5].

Correlates of HIV Testing among Youth

Policy and programmatic efforts to develop effective HIV prevention and treatment programs targeted towards youth living in resource-poor urban settings require empirical evidence on the drivers of HIV-related behavior including HIV testing and counseling. However, although there is substantial evidence that young people in urban slum settlements are more likely to engage in high risk sexual behavior and are at significantly higher risk for HIV infection than their peers in other settings [6, 7, 11–15], we know very little about the HIV testing behavior of youth in general. The limited existing research on the correlates of HIV testing among youth, in general, primarily focuses on attitudes toward HIV testing [16, 17], intentions to test [18], differences in the timing of HIV testing from a life course perspective [19], or the correlates of HIV testing among convenience samples of specific groups of young people at high risk for infection such as gay and bisexual youth [20]. Existing studies provide useful insights on which youth are more likely to get tested for HIV. However, few examine the context under which a person gets tested-that is whether a person is offered the test, volunteers for a test, or whether the test is mandatory; and the motivation for the test. Yet, the motivation for testing and circumstances of the test might have significant bearing on subsequent behavior.

The health belief model (HBM) model [21] provides a useful framework for studying HIV testing behavior among youth. The model posits that a person's likelihood of engaging in a particular health behavior is influenced by his or her perceived susceptibility to the health outcome (e.g., the subjective perception of the risk of contracting HIV), the perceived seriousness of the health outcome (e.g., one's feelings about the medical and social consequences of living with HIV/AIDS), the perceived benefits of preventive actions (e.g., using condoms or being tested for HIV), the perceived barriers or costs of taking a certain health action (e.g., stigma associated with being diagnosed with HIV), cues to action or cues that prompt one to take a certain action (e.g., media campaigns encouraging HIV testing); and self-efficacy or perceived competence in taking a particular health action to mitigate the health condition [21]. Sociodemographic and other structural variables may also influence these perceptions. For example, education may affect access to information about available services, such as HIV testing. Figure 2 illustrates the HBM and shows how study variables fit into the model.

In this study, we 1) explored the linkages between young people's sociodemographic characteristics, HIV-related psychosocial attributes, and HIV testing behavior; and 2) investigated the reasons young people living in urban slum settlements in Nairobi give for testing (or not testing) for HIV. With respect to the first aim, we specifically investigated differences between young people based on 1) HIV testing status (never versus ever tested), and 2) among young people who requested for an HIV test -- which we considered a voluntary test --, those who were offered the test, and those required to take a test (e.g., for employment purposes) -- which we considered a mandatory test. With respect to the HBM constructs, we hypothesized that youth who believed that they were more susceptible to HIV infection, who were worried about HIV infection, who had greater HIV knowledge, and who believed in the benefits of the preventive action of condom use were more likely to have been tested and to have requested an HIV test as opposed to being offered the test or being required to take a test.

Study Setting

We used data collected from youth in two slum settlements in Nairobi. Korogocho slum settlement is one of the oldest and most congested settlements within the city, and many residents have lived there for many years. Viwandani slum settlement is situated in Nairobi's industrial area, and attracts a youthful, highly mobile migrant population seeking employment in industry. Although the slum settlements have different demographic and livelihood profiles, both are characterized by inadequate access to formal health, education and other social services [22, 23]. The combined effects of inadequate health services, poverty, and difficult socio-environmental conditions increase slum dwellers' vulnerability to poor health outcomes [24, 25].

Previous studies suggest that urban poverty [12, 24] and the high mobility of the urban poor [26, 27] may increase vulnerability to HIV/AIDS. According to Krishnan [28], poverty may increase vulnerability to HIV through several pathways including: a greater likelihood to engage in transactional sex; limited access to formal education and skills, which heightens economic dependency especially for women and girls; and limited access to HIV preventive services and health information. On the other hand, high mobility may increase vulnerability to HIV through increased access to casual sexual partners and weakened social controls [27]. Studies conducted in Kenya show that slum dwellers fare much worse in terms of risky sexual behavior when compared to their wealthier urban counterparts or those living in rural areas [12, 14, 29]. For example, Zulu and colleagues [14] observed a 5 year difference in the median age at first sex between those who grew up in slum settlements and those who grew up in other parts of the city. This difference in age at sexual debut remained significant even after controlling for sociodemographic variables such as religion and schooling. Increased vulnerability to HIV among youth living in these resource-poor settings is reflected in the relatively high HIV prevalence observed in 2008; 6% and 3% among 15-19 year old females and males respectively, and 9% and 3% among 20-24 year old females and males, respectively [7]. The high HIV prevalence underscores the need to understand the drivers of HIV-related behavior in order to inform HIV prevention programs targeted towards slum residents.

Study Design, Participants and Procedures

We drew on baseline data from the 3-year (2007-2010) prospective Transition-To-Adulthood (TTA) study. The TTA's general objective was to identify protective and risk factors in the lives of youth growing up in the two slum settlements, and to examine how these factors influence their transition to adulthood. The study was nested in the Nairobi Urban Health and Demographic Surveillance System (NUHDSS), which covers nearly 72,000 people in 28,000 households every year. For the TTA project, a random sample of youth was selected from 2007 NUHDSS household records. During the first wave of data collection (October 2007 to June 2008), 4058 youth aged 12-22 years were interviewed. This number reflects a 77% response rate among eligible randomly-selected youth aged 12-22 years who were resident in the NUHDSS (N = 5,281). Less than 5% of youth who were approached to participate in the study refused to be interviewed. The relatively low response rate is therefore primarily attributable to difficulties in locating some youth, given the high mobility of residents in the area [26]. Respondents did not differ from non-respondents by sex; however, respondents were younger (p < .10) and more likely to be from Korogocho (p < .05). In this study, we limit our analyses to the 4028 (99% of respondents) who answered questions on HIV testing.

A comprehensive interview questionnaire was administered that included questions covering sociodemographic characteristics (e.g. school and religious affiliation); key health and other concerns; and sexual behavior. The questionnaire also included a module on HIV knowledge, HIV testing experiences, and reasons for getting (or not getting) tested. The interviews were conducted in Kiswahili by male and female interviewers, many of whom had previous experience working in the two slum settlements. Most of the interviewers were younger than 30 years of age. Interviewers underwent a 5-day training program that included, among other topics: an introduction to the project; the roles of interviewers, research ethics; and familiarization with the questionnaire. The training also included mock interviews with other interviewers, as well as pilot interviews with a group of youth living in the two slum settlements but outside the study area.

Ethical approval was granted by the Kenya Medical Research Institute's ethical review board. Verbal or signed informed consent was obtained from all respondents. For respondents aged 12-17, consent was also requested from the parent or guardian.

Measures

Analyses

To explore the linkages between young people's sociodemographic characteristics, HIV-related psychosocial attributes, and HIV testing behavior, we first used logistic regression models to compare youth who had been tested for HIV to those who had never been tested. We then used multinomial logit regression models to examine differences among female respondents who requested their most recent HIV test, those offered the test, and those required to take a test. Given the small number of male respondents who reported that their most recent test was required (n = 27), we created a single category coded "0" for those offered the test and those required to take the test. We then ran a logistic regression model to compare the combined group of those offered the test and those required to take the test to those who requested an HIV test. We examined differences across outcome groups based on the primary explanatory variables derived from the HBM as well as sociodemographic and behavioral variables that may influence HIV testing. In sub-Saharan Africa, HIV is predominantly transmitted via sexual intercourse, and previous sexual behavior may influence perceived need for HIV testing. We therefore included sexual experience (ever--coded 1--versus never having had sex--coded 0) as an independent variable.

Reasons for testing (or not testing) may also differ based on whether or not a person has ever had sexual intercourse. Thus, to investigate the reasons young people living in the study communities give for testing decisions, we ran cross tabulations of reasons given by sexual experience. All analyses were conducted separately for males and females as we assume that factors associated with HIV testing behavior are gender sensitive.

Characteristics of Study Population

Experiences with Testing

Overall, although the vast majority of respondents (over 90%) received counseling during their most recent HIV test, about 15% and 13% of males and females, respectively, who were required to take an HIV test did not receive counseling. Over 90% of respondents received their HIV test results. However, 22% of males and 14% of females who were offered the test did not receive their test results. Subsequent analyses (results not shown) indicate that respondents who received counseling were more likely to receive their test results.

Correlates of having been Tested for HIV

To explore the correlates of having been tested for HIV, we first compared young people who had ever been tested for HIV to those reporting no previous test. At the bivariate level (results not shown), males with high HIV knowledge, who were somewhat worried about being infected with HIV relative to those who were not worried, who were older, who were living in Viwandani, were Catholic relative to being Muslim, were out of school, were married, had made someone pregnant, and who had engaged in sexual intercourse were more likely to have ever been tested for HIV. Among females, those with high HIV knowledge, those who believed that condoms prevent HIV transmission, those perceiving a 50-50 chance of HIV infection relative to low perceived risk, those who were somewhat worried about being infected with HIV relative to not being worried, who were older, were Catholic relative to being Muslim, were out of school, were married, who had ever been pregnant, and who had ever had sexual intercourse were more likely to have ever been tested for HIV.

Correlates of the Context under which the Most Recent HIV Test was taken

Among males, age was the only sociodemographic variable associated with the context under which the most recent test was taken at the .05 level of significance. Older males were less likely to have been required/offered the test than to have requested the test. Among females, on the other hand, area of residence, religion, schooling status, and pregnancy history were associated with the reason for testing. Females who were in school were more likely to have been offered the test than to have requested the test. Females who had ever been pregnant were close to 36.5 times more likely to have been required to take the test and 4.0 times more likely to have been offered the test compared to those who had never been pregnant. As with the analyses on the correlates of having tested for HIV, we examined the effect of dropping pregnancy in the multinomial regression model. Once pregnancy was dropped from the model based on data from females (results not shown), schooling, marital status and sexual experience became strongly associated with the outcome variable. Specifically, females in school were more likely to have requested their most recent HIV test than to have been required to take the test, while married respondents and those who had ever had sex were more likely to have been required to take an HIV test than to have requested the test.

Motivations For or Against Testing