Introduction to Behavioral Surveillance Surveys
Family Health International's Behavioral Surveillance Surveys (BSS) provide valuable data about HIV/AIDS-related knowledge, attitudes, and behaviors. The BSS methodology is a monitoring and evaluation tool designed to track trends in HIV/AIDS-related knowledge, attitudes, and behaviors in subpopulations at particular risk of HIV infection, such as female sex workers, injecting drug users, migrant men, and youth. Based on classic HIV and sexually transmitted disease (STD) serologic surveillance methods, BSS consist of repeated cross-sectional surveys conducted systematically to monitor changes in HIV/STD risk behaviors. A key benefit of the methodology is its standardized approach to questionnaire development, sampling frame construction, and survey implementation and analysis. BSS findings serve many purposes: they yield evidence of project impact; provide indicators of project success and highlight persistent problem areas; identify appropriate intervention priority populations; identify specific behaviors in need of change; function as a policy and advocacy tool; and supply comparative data concerning behavioral risks.
Since 1992, BSS have been conducted in more than 20 countries, primarily in Africa and Asia, and their use in Latin America and the Caribbean is growing. Since 1999, they have been used in cross-BORDER=0 sites in Asia and Africa, where they are proving beneficial for understanding the pandemic from a regional rather than purely country-specific perspective. In several countries, multiple rounds of BSS have been implemented already, with the trend data used to formulate new programs and adapt existing ones.
Introduction to Kenya BSS
Kenya represents one of the many African nations with a serious AIDS epidemic. Approximately 2.1 million people were living with AIDS in 1999 in Kenya. One in every 15 adults in Kenya is infected with HIV, and each day an estimated 500 Kenyans die of AIDS. Over the past decade, the adult HIV prevalence rate in Kenya has risen steadily from approximately 3 percent in 1990 to almost 14 percent in 1999. Heterosexual contact accounts for 85 percent of the recorded number of HIV infections in the country, with the prevalence of infection highest among females aged 15-19 and males aged 30-34.
Kenya's response to the HIV/AIDS crisis has focused largely on behavior modification. In an effort to monitor the epidemic and assess the impact of prevention interventions, Kenya health officials have employed an HIV sentinel surveillance system in which data is collected on disease prevalence. However, due to the chronic nature of HIV infection, even the most successful behavior-based interventions are slow to change HIV prevalence in a given target population. As a result, HIV surveillance data cannot indicate whether prevention interventions are having the desired short-term effect of changing behaviors. Therefore, to measure the success of Kenya's HIV interventions, the first wave of BSS was conducted ("BSS I") beginning in 1998 in Mombasa.
Study Design and Methodology
Study population
Data on high-risk subpopulations provide information on groups having the greatest impact on the HIV and STD epidemics. For this reason, subpopulations for BSS primarily consist of groups such as commercial sex workers (CSWs), who are at high risk of becoming infected and passing the infection onto others. Other subpopulations are considered 'bridge' groups and consist of individuals who have significant sexual contact with both high- and low-risk groups. Long distance truck drivers or miners are examples of bridge populations, as they may have contact with non-regular partners and CSWs while away from their regular partners for extended periods of time. Low-risk groups form more broadly defined general populations with varying socio-demographic characteristics, such as workers and students.
For the purposes of the Kenya BSS I, data was collected in 1998 on the following subpopulations: core transmitting groups comprised of Commercial Sex Workers (CSWs); highly vulnerable groups represented by Matatu drivers and touts; and youth both in- and out-of-school. Mombasa was selected as the site for conducting the BSS since the HIV prevalence in this city is high and Mombasa is a major seaport as well as the country's second largest city after Nairobi. The selected subpopulations that participated in the Kenyan BSS I are briefly described below:
|
Kenya BSS Subpopulation Definitions |
|
Commercial Sex Workers (CSW)
Commercial sex workers, females aged 16 to 35-years-old, including higher paid and lower paid workers.
Matatu Drivers and Touts
Matatu (van) drivers and touts (drivers' assistants), males aged 18 to 30 years old.
Youth
In-school male and female youth, the majority aged 15 to 19 years old;
Out-of-school youth including single, unemployed females aged 15 to 19 years old and single, unemployed or part-time working males aged 20 to 24 years old. |
Sample size
The number of participants for each group was determined based on the estimated level of key risk behaviors (such as percentage using condoms with non-regular sex partners) and the degree of confidence required to detect a significant change in behavior over time. Using a probability sampling method for all subgroups, a total of 3,485 participants were included in the survey. Table 1 shows the number of participants included in each subgroup.
Table 1. Subpopulations, Sample Sizes, and Study Sites
|
High Risk Core Group |
Vulnerable Group |
Youth |
Total |
|
Commercial Sex Workers (CSW) |
620 |
Matatu Drivers/Touts |
513 |
Male and Female Youth |
2,352 |
3,485 |
|
Lower Paid |
312 |
|
In-School
Male
Female |
467
754 |
|
Higher Paid |
308 |
Out-of-School
Male
Female |
416
715 |
Sample design
The target groups were sampled using a cluster design defined around naturally occurring units. CSWs, Matatu drivers and touts, and youth all formed natural clusters. A detailed sampling frame was designed that included limiting the sample size in each cluster to a specific number, and then calculating a sampling interval by dividing the total cumulative measure of size by the number of clusters.
Among the three target groups, CSWs and youth were each split into two groups. CSWs were comprised of both "higher paid" and "lower paid" sex workers, with higher paid CSWs working in more expensive venues than lower paid CSWs. The sex workers were selected for the survey using probability random sampling. Youth were split into subgroups based upon whether they were attending school. The in-school subgroup consisted of students attending school within the Mombasa District. Out-of-school youth were randomly selected using a map of the districts where eligible youth were likely to reside. Matatu drivers and touts were randomly selected for the survey using a list of all Matatu routes within the municipality of Mombasa.
Data collection
To collect data from the subpopulations, teams of interviewers were recruited, trained and overseen by supervisors. Three separate surveys were developed for each of the target groups. As a second phase of this survey, investigators used a qualitative data collection technique, whereby a convenience sample of participants in each subpopulation was recruited to participate in separate focus group discussions led by an experienced facilitator.
Results
Sociodemographics
Table 2 provides selected demographic characteristics of the participants in the Kenya BSS I. As depicted in the table, the sample studied is predominately young. Matatu drivers and touts are the oldest, with a median age of 28 years, while students represent the youngest subpopulations with median ages ranging from 17 years for in-school youth to 19 years for out-of-school youth. Higher paid CSWs are slightly younger than lower paid CSWs, with a median age of 23 and 25 years, respectively.
With respect to marital status, a larger percentage of lower paid CSWs had been married in the past (50 percent), as compared to higher paid CSWs (32 percent); only 1 percent of both subgroups of CSWs were married at the time of the survey. While over 50 percent of Matatu drivers and touts had been married in the past, at the time of the survey 37 percent were married. None of the youth were married.
In terms of education, out-of-school youth, with a mean of more than 15 years of education, had the greatest amount of schooling compared to the other groups. Matatu drivers and touts followed with a mean of 14 years of education. Higher paid CSWs had the least education with a mean of 8.5 years. More than 90 percent of all of the subpopulations surveyed had attended school at some time.
Table 2. Selected Sociodemographic Characteristics, All Groups
|
Variable |
Higher Paid CSW |
Lower Paid CSW |
Matatu Drivers/Touts |
In-School Youth |
Out-of-School Youth |
|
Median Age (years)
Marriage
% Ever Married
% Currently Married
Education
Mean years of schooling
% never attended |
23
32
1
8.5
7 |
25
50
1
8.9
5 |
28
55
37
14
5 |
17
0
0
12.11
0 |
19
0
0
15.13
7 |
Commercial Sex Worker (CSW) Results
Trends in BSS indicators
Knowledge of HIV/AIDS
CSWs revealed widely held misconceptions about ways to prevent transmission of HIV. Differences between lower and higher paid CSWs were not meaningful, in that both groups displayed similar knowledge regarding myths about HIV transmission. Figure 1 provides the combined results of all CSWs in response to some misconceptions about preventing HIV.
Figure 1. Percentage of CSWs identifying popular misconceptions as correct methods of HIV prevention
Behavioral Indicators
Results of the survey showed that higher paid and lower paid CSWs were similar with respect to sexual behavior. The median age at first intercourse was 16 years. CSWs have about 3 sexual partners per week and an average of nearly 14 sex partners each month. CSWs claim that they initiate safe sex with their partners most of the time; they also claim to provide the condom in most sexual encounters with all partners. A greater percentage of CSWs reported consistent condom use with one-time clients (84 percent) and regular clients (77 percent) than with nonpaying partners (43 percent). Ninety-seven percent of CSWs said they used a condom with their last one-time client, 88 percent with their last regular partner, and 54 percent with their last nonpaying partner.
Sex workers cited different reasons for not using a condom with their last sex partner. These reasons vary depending on the type of sex partner, as depicted in Figure 2. Clients' objection to condoms was the main reason CSWs mentioned for not using condoms with paying clients. With nonpaying partners, both partner trust and reduction of pleasure with condoms were main reasons given for not using a condom. Nearly 30 percent of CSWs believed that condom use was unnecessary with nonpaying partners. More than 80 percent of the CSWs said they would use a female condom if it were available, but only between 2 and 4 percent said they know where to obtain one or were able to obtain one.
Figure 2. Reasons for CSW Not Using A Condom With Last Partner
Matatu drivers and Touts Results
Trends in BSS indicators
Knowledge of HIV/AIDS
All Matatu drivers and touts who responded to the survey had heard of AIDS and more than 90 percent knew that AIDS was preventable. Figure 3 shows that Matatu drivers/touts also have misconceptions about correct HIV prevention methods.
Figure 3. Percentage of Matatu Identifying Popular Misconceptions as Correct Methods of HIV Prevention
Behavioral Indicators
Matatu drivers and touts reported an average of 8 sexual partners in the 12-month period preceding the survey. Of these partners, the majority (55 percent) were regular partners, including a steady girlfriend or spouse. Thirty percent of Matatu drivers' sexual partners in the 12 months preceding the survey were non-regular partners and 14 percent were CSWs. A greater percentage of Matatu drivers and touts reported consistent condom use with CSWs (61 percent) and non-regular partners (38 percent) than with regular partners (12 percent). Seventy-five percent of Matatu drivers said they used a condom with their last commercial sex partner, 52 percent with their last non-regular partner, and only 16 percent with their last regular partner.
Figure 4 shows that of the 25 percent of Matatu drivers and touts not using a condom with a CSW, most thought it was either not necessary or that using a condom reduced pleasure. Of the 85 percent of these men who said that they did not use a condom with their regular partner, most of them reported not using one because they trusted their partner or they did not think it was necessary. With all three partner types, Matatu drivers and touts claimed to initiate safe sex with the partner most of the time.
Figure 4. Reasons for Matatu Not Using A Condom With Last Partner
Youth Results
Trends in BSS indicators
Knowledge of HIV/AIDS
Overall, youth are significantly more knowledgeable than both CSWs and Matatu drivers about prevention methods for HIV (p<.05). However, Figure 5 reveals that, like the other study groups, youth hold misconceptions about HIV prevention. Out-of-school youth are less clear about ways to prevent HIV than in-school youth. A comparatively high percentage of out-of-school females are misinformed about modes of transmission. Nearly a quarter of this group believes that ways to prevent HIV transmission include avoiding mosquito bites, avoiding sharing food with infected persons and avoiding public toilets. Nearly 40 percent believe kissing can transmit HIV infection.
Figure 5. Percentage of Youth Identifying Popular Misconceptions as Correct Methods of HIV Prevention
Behavioral Indicators
Out-of-school youth reported having slightly more sexual experience than in-school youth. Very few female youth reported having had multiple sexual partners in their lifetime, or more than one partner in the past three months. Females, both in- and out-of-school, tended to report engaging in sex with older men, whereas most males reported having sex with younger females.
While most youth have heard of condoms, the percentage of female out-of-school youth who have heard of condoms is much lower. As shown in Figure 6, 90 percent of all male youth said they were able to obtain a condom when they needed one. Nearly 70 percent of in-school females reported being able to obtain a condom, whereas only 30 percent of out-of-school females reported being able to do so. Although the percentage of youth who used a condom in their first sexual encounter was less than 30 percent for all groups, more females than males used a condom their first time.
Figure 6. Youth Condom Access and Use
Figure 7 displays responses to whether youth used a condom with their last three sexual partners. Although there was a 50 percent increase in condom use among in-school females from their first to their third partner, the reason for this sharp increase is that only two in-school females had three sexual partners and both used a condom. A significantly greater percentage of in-school males also used condoms with their third partner, with an increase from 48 percent to 74 percent from their first to their third partner (p<.05). Out-of-school males had no significant change in condom use (p>.05). Out-of-school females reported a decreased use of condoms from their first to their third partner, from 22 percent to 13 percent, but as with in-school females this change was based on numbers too small to be statistically meaningful.
Figure 7. Youth Condom Use With Last Three Sexual Partners
Summary of Findings
The data collected in the Kenya BSS I supports the following conclusions:
Commercial Sex Workers
- CSWs had more knowledge about HIV prevention than the other groups surveyed; they had better knowledge about prevention methods and believed fewer myths about HIV/AIDS.
- Among all CSWs, condom use is higher with paying clients versus nonpaying clients.
- The majority of CSWs said they would use a female condom if it were available, but very few knew where to obtain one or were able to obtain one.
Matatu Drivers/Touts
- Matatu drivers/touts had less knowledge about correct HIV prevention methods than CSWs .
- The majority of the drivers' partners were regular partners, including a girlfriend or spouse. Matatu drivers/touts were less likely to use condoms with regular partners than with CSWs and non-regular partners.
- Matatu drivers/touts do not use condoms with CSWs mainly because they do not think it is necessary and because a condom reduces pleasure.
Youth
- Compared to all other groups, in-school youth demonstrated the greatest knowledge about condom use and HIV.
- Out-of-school youth reported lower condom use, less knowledge and less access to condoms than in-school youth.
- A comparatively high percentage of out-of-school females demonstrated less knowledge about correct ways to contract HIV and reported less access to condoms than other youth.
Recommendations
This round of surveillance provides important insight into the sub-populations studied. It is clear from the survey results that more intensive behavior change interventions are required to increase condom use and dispel myths about HIV transmission. All sub-populations revealed a lack of knowledge about HIV. Many believed myths about HIV prevention and a relatively high percentage of Matatu drivers and touts could name only one or no effective prevention methods for HIV. Matatu business is just one industry employing young people. If this outcome is an indication of an ongoing trend in other workplaces as well, then an intensive workplace peer education program is needed to address this problem.
Matatus are a popular means of transport for the young people to and from school. In this process a relationship may develop between the school girls and the matatu touts whereby the touts allow the girls 'free rides' to and from school in exchange for sexual favors. A strong school-based HIV/AIDS program should be instituted to target schoolgirls with relevant HIV prevention messages. Work with the Ministry of Education and organizations such as the Girl Guides should be reinforced and expanded.
Female youth also need better access to condoms. Behavior Change Communication (BCC) programs should be targeted to out-of-school youth, especially girls, who have the least exposure to information about HIV/AIDS. While fear of pregnancy is an important deterrent to unprotected sexual behavior, this group lacks an understanding of the significance of HIV. This calls for an education and behavior change program with low income community women and girls.
Higher paid commercial sex workers displayed somewhat less knowledge about HIV/AIDS than lower paid CSWs. This group should be targeted for more education on HIV and condom use. CSWs should be empowered to insist on condom use with all of their sexual partners, not just their paying clients but their regular nonpaying partners as well.
While survey results showed that Matatu drivers tend to initiate safe sex practices, they also displayed lack of knowledge about HIV and the importance of condom use. A surprisingly high percentage believed that sex with a condom was not necessary with a CSW -- a highly risky partner. This reveals the need to further target Matatu drivers and touts and men in other industries for behavior change. Matatu and truck drivers and men in the workplace should receive more attention in HIV and AIDS programming in Mombasa.
Given that more than 50 percent of CSWs in the study had never been tested for HIV despite knowing where such services could be obtained, and given the lack of knowledge of HIV status among the other sub-populations studied, it will be important to establish and promote client-friendly HIV voluntary counseling and testing (VCT) centers to attract these population groups. HIV VCT centers are now being established in Mombasa and it is expected that in subsequent BSS, there will be an increase in knowledge of one's HIV status.
For more information, see the following technical guidelines:
UNAIDS and Family Health International, May 1998. Meeting the Behavioural Data Collection Needs of National HIV/AIDS and STD Programmes.
Discusses behavioral data collection needs by different epidemic state. Reflects recent thinking about the best use of resources in behavioral data collection in the context of second generation surveillance.
Family Health International, June 2000. Behavioural Surveillance Surveys (BSS): Guidelines for Repeated Behavioral Surveys in Populations at Risk for HIV.
Provides how-to information that includes identifying priority subpopulations, developing sampling frameworks and approaches, and suggesting analysis and dissemination strategies. Also includes sample questionnaires.
UNAIDS and WHO, 2000. Guidelines for Second Generation HIV Surveillance.
Provides an overview of the principal issues that need to be considered in strengthening surveillance systems and increasing their utility. Suggests priority approaches for the various epidemic states.
Conclusions
Except for in-school youth, CSWs had more knowledge about HIV than other groups; they had better knowledge about prevention methods and believed fewer myths about HIV/AIDS. From the survey results, it appears that lower paid CSWs are better informed and practice safer sexual behavior than their high-paid counterparts. Lower paid workers are also better able to obtain a condom, and can describe more accurate HIV prevention methods than high-paid workers. These differences could be explained by the more frequent communication and interaction among lower paid workers than among the high-paid workers. The intense competition between higher paid CSWs results in less communication among these workers and therefore less exchange of information. For all CSWs, condom use is relatively good with paying clients, but there is room for improvement. Although comparatively few of their sex partners are nonpaying partners, a low percentage of CSWs use a condom with their nonpaying client.
CSWs were more knowledgeable about effective methods for preventing HIV than Matatu drivers and touts. Fewer than half of Matatu drivers/touts use a condom with non-regular partners and they only use a condom with CSWs 60 percent of the time. One of the main reasons cited by these men for not using condoms with CSWs is that they do not think this is necessary.
In-school youth demonstrated more knowledge than the other groups about condom use and HIV. And while out-of-school youth were more likely to engage in sex, they were also less likely to use a condom. Out-of-school youth reported lower condom use, less knowledge and less access to condoms than in-school youth. Out-of-school females had the least knowledge about AIDS, compared to all other groups surveyed. Fewer girls in this group had heard of AIDS or knew correct ways to prevent infection.
Acknowledgments
The Kenya BSS were executed by:
Executed by Steadman Research Services
Administered by:
Republic of Kenya, Ministry of Health, National AIDS/STD Control Program
With technical assistance from:
Family Health International and Sara B. Newman, Consultant
Funded by:
US Agency for International Development (USAID)
Family Health International
This executive summary is based on the following reports:
Behavioral Surveillance Survey: Mombasa, Kenya 1998, Commercial Sex Workers, Matatu Drivers/Touts, Youth. Family Health International, Steadman Research Services, Kenya National AIDS/STD Control Programme.
