Abstract

Background

Hepatitis B is a significant health problem worldwide, particularly among high-risk groups such as female sex workers (FSWs). In Uganda, it is highly recommended that FSWs receive the hepatitis B vaccine. However, there is limited evidence of the level of uptake of the hepatitis B vaccine and associated factors among FSWs in Uganda. This study aimed to assess hepatitis B vaccine uptake and associated factors among FSWs in Kampala district, Uganda.

Methods

We conducted a cross-sectional study using data from 400 FSWs in Kampala, Uganda. We utilized a researcher-developed digitized semi-structured questionnaire and employed multistage sampling to enroll participants. Data analysis was performed using STATA version 14.0. Continuous data were expressed as mean and standard deviation whereas categorical data were reported as frequencies and proportions. We employed Modified Poisson regression analysis to assess the relationship between predictor variables and the uptake of the hepatitis B vaccine.

Results

A total of 400 respondents (98.5% response rate) were surveyed. Close to half, 49.8% of the respondents had ever heard about hepatitis B, and only 16.5% had received at least a hepatitis B vaccine dose. Individual factors significantly associated with hepatitis B vaccine uptake included spending more than four years in sex work (APR: 1.06, 95% CI: 1.01鈥�1.12), previous screening for hepatitis B (APR: 1.49, 95% CI: 1.38鈥�1.61), and having work conditions that allowed time to seek HBV services (APR: 1.13, 95% CI: 1.04鈥�1.22). Health system factors significantly associated with vaccine uptake included the presence of hepatitis B outreach programs in residential areas (APR: 1.17, 95% CI: 1.03鈥�1.33) and receiving information about hepatitis B from peers (APR: 1.07, 95% CI: 1.05鈥�1.31).

Conclusion

The study revealed a low prevalence of hepatitis B vaccine uptake among FSWs, with less than a tenth completing the three-dose schedule. Therefore, enhancing screening programs, expanding outreach initiatives, and tailoring services to accommodate nontraditional work hours while leveraging peer networks can significantly improve vaccine uptake and reduce hepatitis B transmission in this high-risk population.

Background

Hepatitis B remains a major global health problem [1]. The WHO estimates that 254听million people are living with chronic hepatitis B infection, leading to about 1.1听million deaths in 2022 worldwide [1]. The WHO African Region has the second highest burden of hepatitis B globally, with 65听million people affected [1]. In Uganda, hepatitis B is endemic, with a decline in prevalence rates from 10% in 2005 to 4.3% in 2018 (5.6% among men and 3.1% among women) [2, 3]. The in-country distribution of the virus varies by region, with the highest prevalence in the mid-north at 4.6% and the lowest in the southwestern region at 0.8% [2, 4]. Hepatitis B is a viral infection that attacks the liver, causing acute and chronic disease [1]. If left untreated, chronic hepatitis B may progress to liver damage, liver failure, liver cancer, and even death [5]. Due to its often asymptomatic nature, individuals infected with hepatitis B may remain undiagnosed until these severe liver complications emerge.

High-risk groups such as female sex workers (FSWs) are particularly vulnerable to hepatitis B virus (HBV) infection due to the nature of their work [6,7,8]. Their professional activities often involve high-risk behaviours such as engaging in unprotected sex, having multiple sexual partners, and participating in anal intercourse [6,7,8]. These practices significantly increase the risk of exposure to HBV [1]. Additionally, the use of drugs and other substances among some FSWs can further exacerbate risky behaviours and impair decision-making [9, 10]. In response to this elevated risk, hepatitis B vaccination is strongly recommended for FSWs in Uganda and other regions [1].

The World Health Organization (WHO) established robust frameworks to end significant public health threats, including hepatitis B, under its Global Health Sector Strategies (GHSSs) by the target year of 2030. Recognising the increased vulnerability of high-risk groups, including FSWs, the GHSSs emphasize scaling up prevention, testing, and treatment services for viral hepatitis, particularly hepatitis B [1, 11]. Uganda鈥檚 Ministry of Health (MOH) has made significant strides, mainly through mandatory testing of all adolescents and adults born before 2002, vaccination for those who test negative, and linking those who test positive to further evaluation, treatment, and monitoring [12]. Additional efforts include the integration of the HBV vaccine into its Expanded Programme on Immunization (EPI) in 2002 [14]. The vaccine is administered to infants aged 6, 10, and 14 weeks [3, 13]. This schedule, however, means that Ugandan adults born before 2002 did not receive the vaccine as infants and thus have a higher risk of HBV infection, as they were not covered by the early immunisation program [14].

The availability and affordability of the HBV vaccine in Uganda are critical components of the country鈥檚 strategy to combat hepatitis B [15, 16]. The vaccine is available through public health facilities and various non-governmental organizations, often at no cost or highly subsidized rates for at-risk populations, including FSWs [15, 16]. Despite these efforts, challenges remain in ensuring widespread vaccine uptake due to factors such as limited access to healthcare services, stigma, and a lack of awareness about the vaccine鈥檚 importance [16, 17]. To specifically reach high-risk groups like FSWs, the MOH has implemented targeted outreach programs that offer vaccination services in locations accessible to these populations [15]. These programs often involve mobile clinics and collaboration with community-based organizations that work closely with FSWs to provide health education, vaccination, and other essential healthcare services [13]. Regardless, the MOH also actively promotes the vaccination of high-risk groups, such as FSWs, to curb the spread of HBV and protect these vulnerable populations [13]. However, available evidence indicates that FSWs have limited access to healthcare services, possibly hindering vaccine uptake [18, 19].

That notwithstanding, there is limited evidence of the level of uptake of the hepatitis B vaccine and associated factors among brothel-based FSWs in Uganda. Several independent variables, such as accessibility to healthcare services, knowledge about the disease and the vaccine, socio-economic status, and support from healthcare providers, have been identified in the literature as influential factors in vaccine uptake [20,21,22]. Understanding the predictors of hepatitis B vaccine uptake among brothel-based FSWs will inform the design of effective strategies that enhance vaccine acceptance and coverage within this high-risk group and ultimately contribute to eliminating viral hepatitis as a public health threat by 2030. This study used both the Andersen and Newman Framework of Health Services Utilization and the Health Belief Model (HBM) to establish the factors associated with the uptake of the Hepatitis B vaccine among brothel-based FSWs.

Materials and methods

Study design and setting

We conducted a cross-sectional study among brothel-based FSWs in Kampala City, Uganda鈥檚 capital and central administrative center. Kampala comprises five divisions: Central, Kawempe, Makindye, Nakawa, and Rubaga. This study was conducted in two divisions within Kampala City, Makindye and Kawempe, selected due to their high concentrations of FSWs and the availability of healthcare services. Kampala has an estimated population of about 1,500,000 people, with a significant proportion (60%) residing in informal settlements [23, 24]. The city is a hotspot for FSWs [25] and has 1,458 healthcare facilities [26]. In 2021, the MOH in Uganda launched Phase 4 of its Hepatitis B control initiatives, targeting 31 districts, including Kampala. Within Kampala City, 88 healthcare facilities offer hepatitis B prevention services: 22 in Kawempe, 17 in Central, 21 in Nakawa, 17 in Makindye, and 11 in Rubaga [12]. Additionally, eight private hospitals in Kampala have been designated to handle hepatitis B vaccinations: Nsambya Hospital, Kibuli Hospital, Mengo Hospital, International Hospital Kampala (IHK), Norvik Hospital, Case Hospital, Nakasero Hospital, and Rubaga Hospital [12]. Public health facilities provide these vaccinations free of charge while private facilities may charge a fee. The MOH has also designated several health centers in each division of Kampala to serve as hepatitis B treatment centers, i.e., two in Central, Makindye, and Rubaga divisions each, four serve Nakawa division and five serve Kawempe division [12].

Theoretical framework

This study utilized both the Andersen and Newman Framework of Health Services Utilization and the Health Belief Model (HBM) to establish the factors associated with the uptake of the hepatitis B vaccine among brothel-based FSWs. The Andersen and Newman Framework of Health Services Utilization is a conceptual model aimed at demonstrating the factors that either facilitate or impede the utilisation of healthcare services [27]. These factors are classified as predisposing factors (e.g. education, occupation, ethnicity, social networks, social interactions, and culture), enabling factors (such as the logistical aspects of obtaining care), and the perceived need among the population at risk [27]. The HBM is a social psychological health behavior change model developed to explain and predict health-related behaviors, particularly regarding the uptake of health services [28]. The HBM provides insight into individual beliefs about health conditions, perceived benefits of action, and barriers to action. Both models have been applied in previous studies to explore facilitators and barriers to health service utilization [29,30,31,32,33]. The integration of these models allowed for a nuanced understanding of the multi-faceted determinants of hepatitis B vaccine uptake among brothel-based FSWs, ensuring that the interventions designed are both theoretically sound and practically applicable (Fig.听1).

Fig. 1

A conceptual framework of the factors associated with Hepatitis B vaccination (Based on the Andersen model and HBM)

Study population, eligibility, and sample size estimation

The study targeted brothel-based FSWs aged 18 years and older who resided or worked in Makindye and Kawempe divisions. We excluded FSWs who had lived or worked in the area for less than six months. While the study specifically targeted brothel-based FSWs, many respondents reported engaging in multiple modes of operation, including street-based sex work, to expand their clientele. This dual engagement is common among sex workers, who may operate from brothels while also seeking clients in other settings, such as on the streets or through phone-based arrangements. This overlap reflects the fluid and adaptive nature of their work environments and was captured during the interviews to provide a comprehensive understanding of their practices.

The Kish Leslie formula for cross-sectional studies was used to estimate the sample size, assuming a 50% prevalence of hepatitis B vaccine uptake among brothel-based FSWs, a 95% confidence interval (1.96), a precision of 5%, and a 5% non-response rate, yielding a minimum sample size of 406 FSWs. A 5% non-response rate was factored into the study to account for the potential fear of disclosure among the study population and to ensure that the sample remains representative of the broader community [34].

Sampling procedure

A multistage sampling technique was employed to select the study respondents. In the first stage, the research team purposively selected the Makindye and Kawempe divisions due to their higher volumes of FSWs [35, 36]. The second stage involved randomly selecting five brothels per division from a list obtained from the respective leadership. The third stage involved obtaining a list of FSWs from the respective brothel managers. After that, we employed simple random sampling to select the study participants using a Microsoft Excel randomiser.

Study variables

Dependent/outcome variable

The outcome variable was binary, indicating whether the participant had received at least one dose of the hepatitis B vaccine at any point(yes/no).

Independent variables

The independent variables included individual factors such as age, marital status, religion, the highest level of education completed, other occupations, years lived in the area, years spent in sex work, ways of getting sex clients, perceived social status, and psychoactive substance use. Other individual factors included hepatitis B risk perception and knowledge of hepatitis B. The health system factors included the type of healthcare facility the FSW typically visited for medical services, including vaccinations; friendliness and approachability of the staff; level of satisfaction with the services; availability of health education on various conditions, including hepatitis B; waiting times; the presence of health outreach programs; distance traveled to the healthcare facility used to access medical services; mode of transportation to the healthcare facility; and availability of educational materials on hepatitis B.

Data collection procedures, and quality control and assurance

We used face-to-face interviews aided by a digitalized semi-structured to obtain data on hepatitis B vaccine uptake from brothel-based FSWs. The research team developed the questionnaire (supplementary file 1) used in this study after thoroughly reviewing existing validated tools on hepatitis B vaccination [37,38,39,40,41]. The questionnaire included sections on individual factors, health system factors, and uptake of hepatitis B vaccination. The tool was programmed in Kobocollect with automated skip patterns to prevent errors in question flow and ensure that respondents only answered questions relevant to their previous responses [38]. The study was conducted over one month (May 2023). The data collection was carried out by a team of trained research assistants who were specifically recruited for this study. The research assistants had backgrounds in public health and experience in conducting surveys among key populations, such as FSWs. Before data collection commenced, the research team underwent a three-day training covering the study objectives, data collection procedures, ethical considerations, and the use of the KoboCollect electronic data collection tool. The training also included mock interviews and role-playing exercises to ensure that data collectors were familiar with the questionnaire and could handle potential challenges in the field, such as addressing sensitive topics. After training, the tool was pretested with a subset of respondents in a different division (Central Division, Kampala). Feedback from the pretest was used to refine questions, improve clarity, and adjust skip patterns and response options to ensure accuracy and ease of use. During data collection, research assistants approached eligible FSWs at the brothels and explained the purpose of the study. The research assistants uploaded the data from the field to a secure, password-protected server daily to reduce the risk of loss and to enable real-time quality control measures. Only authorized research team members had access to the data, and all data were anonymized by removing identifying information before analysis. Additionally, data transmission between mobile devices and the server was encrypted, minimizing the risk of unauthorized access. During the data collection, the core team thoroughly supervised the research assistants and held field debriefs to ensure quality. The supervisory team used debrief meetings to address any discrepancies during the fieldwork.

Data management and analysis

After data collection, the data manager downloaded the data in Microsoft Excel format (XLS) for cleaning. An initial review was conducted to check for completeness, missing values, and any obvious errors. The dataset was reviewed for inconsistencies, such as duplicate entries, outliers, and illogical responses (e.g., age values outside the expected range). These inconsistencies were identified using Excel filters and conditional formatting. Since the electronic questionnaire used automated skip patterns, a check was performed to ensure that responses adhered to the predefined logic. For instance, participants who answered 鈥淣o鈥� to receiving the Hepatitis B vaccine should not have subsequent responses related to vaccination details. Any discrepancies were corrected based on the intended skip logic. After cleaning, the dataset was exported from Excel to Stata version 14.0 for analysis. Continuous data were expressed as mean and standard deviation whereas categorical data were reported as frequencies and proportions. Descriptive statistics were performed to summarize continuous (mean and standard deviation) and categorical variables (frequencies and proportions). For inferential analysis, modified Poisson regression with robust standard errors was used at both the bivariate and multivariable stages. The modified Poisson regression model was selected due to its suitability for cross-sectional studies where the outcome (vaccine uptake) is common. Bivariate analysis was performed to establish the relationship between each independent predictor and the outcome, i.e., the uptake of the hepatitis B vaccine. Variables with a p-value鈥夆墹鈥�0.25 were included in the Modified鈥� Poisson regression model to establish factors associated with the uptake of hepatitis B vaccination among brothel-based FSWs. The cut-off p-value 鈮�0.25 was used since more traditional levels, such as 0.05, often fail to identify important variables for further analysis [42]. A stepwise backward elimination approach was used to refine the model. Variables were systematically removed based on their statistical significance, with the least significant variables being dropped first. At each step, the model was reassessed to ensure that removing a variable did not significantly reduce the model鈥檚 explanatory power. The final model included only variables that were statistically significant at p鈥�<鈥�0.05. The model鈥檚 fit was assessed using the Hosmer-Lemeshow test, and multicollinearity was evaluated using the variance inflation factor (VIF), with a VIF鈥�>鈥�10 indicating high multicollinearity. Adjusted prevalence ratios (APRs) with 95% confidence intervals (CIs) were reported to determine factors independently associated with vaccine uptake, controlling for potential confounders. A p-value鈥�<鈥�0.05 was considered statistically significant.

Results

Social demographic characteristics

Of the 400 respondents surveyed, 50.3% were aged 25鈥�35 years, and 58.8% were divorced. Nearly half (45.5%) were Roman Catholic, and 45.8% had completed primary education at their highest level. About 38.5% reported having an additional source of income beyond sex work. Two thirds 66.3% of the respondents had lived in the area for more than 5 years, while 44.0% had been engaged in sex work for over 4 years. A majority 65.8%听of the respondents mentioned that their clients were mainly street-based, and 77.0% had a low perceived social status (Table听1).

Table 1 Social demographic characteristics of the respondents

Respondent鈥檚 expenditure

The median amount clients paid for a 鈥渟hort鈥� session was UGX 5,000 (IQR鈥�=鈥�5,000鈥�7,375), while for a 鈥渓ong鈥� session, it was UGX 15,000 (IQR鈥�=鈥�10,000鈥�25,000). Respondents reported a median daily expenditure of UGX 10,000 (IQR鈥�=鈥�10,000鈥�18,000). The maximum payment received for a 鈥渟hort鈥� and 鈥渓ong鈥� session was UGX 100,000 and UGX 200,000, respectively (Table听2).

Table 2 Respondent鈥檚 daily expenditure and on clients

Hepatitis B vaccination status

Nearly half 49.8% of the respondents had ever heard of hepatitis B, with healthcare facilities being the primary source of information (61.3%). However, only 16.5% had received at least one dose of the hepatitis B vaccine, and 5.5% had completed the recommended three doses. Among those aware of hepatitis B, 57.8% perceived themselves to be at risk, but only 45.7% of them considered the risk to be high (Table听3).

Table 3 Awareness, risk perception, and uptake of the hepatitis B vaccine among female sex workers in Kampala, Uganda

Knowledge of hepatitis B transmission

Knowledge of hepatitis B transmission was limited, with only 22.1% identifying unprotected sexual intercourse as a mode of transmission, while smaller proportions mentioned transmission through blood (7.0%) and sharps/needles (1.5%) (Fig.听2).

Fig. 2

Knowledge of hepatitis B transmission of hepatitis B among female sex workers in Kampala, Uganda

Reasons for not receiving the hepatitis B vaccination

The most common reasons for not receiving the hepatitis B vaccine included a lack of awareness (30.1%), not knowing where to access vaccination services (27.1%), and perceiving no need for the vaccine (23.3%). Fewer respondents cited cost (6.0%) or fear of the vaccine (2.3%) as reasons (Fig.听3).

Fig. 3

Reasons for not receiving the hepatitis B vaccination among female sex workers in Kampala, Uganda

Characteristics of the healthcare system/facilities used by the respondents

Nearly three quarters 73.0%听of the respondents used public healthcare facilities, with 61.5% reporting that healthcare workers were friendly, and 60.8% expressing satisfaction with services. However, only 23.5% mentioned the presence of hepatitis B information, education, and communication materials at the facilities they visited. Additionally, 14.2% reported health-related outreaches in their areas (Table听4).

Table 4 Characteristics of the healthcare system/facilities used by female sex workers in Kampala, Uganda

Individual factors associated with the uptake of hepatitis B vaccination services

After adjusting for age category, only the years spent in sex work, ever being screened for Hepatitis B and the nature of the job which allowed the respondent to get time to seek HBV services were statistically significant with the uptake of hepatitis B vaccination services. The prevalence of uptake of hepatitis B vaccination was 6.0% higher among respondents who had spent more than 4 years in sex work compared to those who had spent between 0 and 4 years (APR: 1.06, 95%CI: 1.01鈥�1.12). The prevalence of uptake of hepatitis B vaccination was 49.0% higher among respondents who had ever been screened for hepatitis B compared to those who had not (APR: 1.49, 95%CI: 1.38鈥�1.61). The prevalence of uptake of hepatitis B vaccination was 13.0% higher among respondents who mentioned that the nature of their jobs allowed them to get time to seek HBV services, compared to those who did not (APR: 1.13, 95%CI: 1.04鈥�1.22) (Table听5).

Table 5 Individual factors associated with uptake of Hepatitis B vaccination services among female sex workers in Kampala Uganda

Health system factors associated with uptake of hepatitis B vaccination services

After adjusting for age and the highest level of education completed, health-related outreaches on hepatitis B in the area where the respondent lives and receiving information related to hepatitis B from peers were statistically significant with the uptake of hepatitis B vaccination services. The prevalence of uptake of hepatitis B vaccination was 17.0% higher among respondents who had received some hepatitis B outreaches in the areas where they lived compared to those who had not (APR: 1.17, 95%CI: 1.03鈥�1.33). The prevalence of uptake of hepatitis B vaccination was 7.0% higher among respondents who had ever received information related to hepatitis B from their peers, compared to those who had not, (APR: 1.07, 95%CI: 1.05鈥�1.31) (Table听6).

Table 6 Health system factors associated with uptake of Hepatitis B vaccination services among female sex workers in Kampala, Uganda

Discussion

This study aimed to assess individual and healthcare system factors associated with the uptake of hepatitis B vaccination among brothel-based FSWs in Kampala City, Uganda. The findings reveal that the prevalence of hepatitis B vaccine uptake among brothel-based FSWs in Kampala, Uganda was less than a quarter (16.5%). Moreover, less than a tenth (5.5%) had completed the three hepatitis B doses, and 4.5% reported being diagnosed with the infection. The uptake of the hepatitis B vaccine was significantly associated with several factors including spending more than four years in sex work,听prior screening for hepatitis B, the nature of the job of the respondent which allowed time to access HBV services, the presence of health-related outreach programs on hepatitis B in the respondent鈥檚 area of residence, and receiving hepatitis B-related information from peers.听FSWs who had spent more than four years in the occupation (sex work) had a higher probability of taking the hepatitis B vaccine. FSWs who spend a considerable period in the occupation are more likely to be targeted for the surveillance and treatment programs for sexually transmitted infections, including HBV, as opposed to those who do not. These treatment programs provide an opportunity to create awareness of hepatitis B, thereby influencing vaccine uptake. Spending more time in sex work increases awareness of the associated risks, including unprotected sexual intercourse and sharing of non-sterile needles, which are widely reported in the literature as modes of transmission of HBV [43, 44]).

FSWs who had ever been screened for hepatitis B had a higher chance of taking the hepatitis B vaccine. Screening for hepatitis B can be a gateway for accessing information on hepatitis B and vaccination services. FSWs who screen are more likely to interface with healthcare providers who can demystify any misconceptions, and healthcare educates the FSWs on the HBV risk posed by their occupation. Through this interaction, healthcare workers provide information to the FSW on transmission, the importance, and the benefits of going the extra mile to be vaccinated against hepatitis B. Aside, most screening programs also provide vaccination. Although not always, hepatitis B vaccinations are provided after screening, thus a positive correlation between screening and vaccination. The positive correlation between screening and uptake of hepatitis B vaccine has also been reported among other high-risk groups in Uganda [38, 45]. Our findings thus emphasise the need to use screening programs to increase vaccine uptake among FSWs. A similar recommendation has been made by other scholars [6, 46]. Therefore, screening programs should be leveraged to increase hepatitis B vaccine uptake among FSWs by incorporating education and vaccination into these services. This integrated approach can help address barriers, improve coverage, and reduce hepatitis B transmission in this high-risk population.

FSWs who believed that the nature of their job allowed them to get time to seek hepatitis B services. Time is often reported as a hindrance to the uptake of healthcare services, including vaccination [47,48,49,50]. Thus, FSWs who exhibit flexibility in their working hours are not surprisingly more likely to uptake hepatitis B vaccination services. The current study found that nearly two-thirds of the FSWs were street-based, which means that they worked during the night [51] and could therefore access vaccination services since these are offered during the day. Healthcare providers should consider scheduling services at times that accommodate populations with nontraditional work hours, such as FSWs. Additionally, outreach programs could be tailored to provide services during the evening or night to further enhance accessibility. Addressing time-related barriers can improve vaccination rates and contribute to better health outcomes in high-risk groups.

The uptake of the hepatitis B vaccine was higher among FSWs who lived in areas that had had some health-related outreaches on hepatitis B. Community health-related outreaches aim to increase access to hepatitis B-related services such as screening/ testing and vaccination, and information including transmission, signs and symptoms, preventive measures, and treatment. Health-related outreaches can be used to demystify misconceptions and to influence health-seeking behaviors thus increasing the uptake of hepatitis B vaccination. Aside, health-related outreaches are also known to provide free or subsidized screening and vaccination services which can act as a driver to the uptake of the vaccine among hard-to-reach populations, including FSWs. Our findings are consistent with those of the previous studies [46, 52,53,54], which indicated an increase in hepatitis B vaccination as a result of outreaches. This study implies the use of outreaches provides an opportunity to reach and thus increase the uptake of hepatitis B vaccination among FSWs, who are reported to be a hidden population [55, 56]. Therefore, expanding outreach programs to include hepatitis B services can help address vaccination gaps in hidden populations like FSWs. Policymakers and healthcare providers should prioritize outreach efforts, as they are a cost-effective and impactful approach to improving vaccine uptake, reducing hepatitis B transmission, and promoting overall health equity.

FSWs who had ever received information related to hepatitis B from their peers were more likely to uptake the vaccine compared to those who had not. Peers are often reported by FSWs as an important source of health-related information. These believe that peers often have the desired experience, often accrued from the utilisation of a particular health service, and are in a better position to provide any health-related advice. It is possible that the information that was received from the peers positively contributed to the uptake of the vaccine. The role of peers in driving the uptake of healthcare services among FSWs is widely reported in the literature [57,58,59,60]. This study, therefore, calls upon health authorities and other relevant stakeholders to utilise peers to increase the uptake of hepatitis B vaccination among FSWs.

Conclusions and recommendations

This study revealed a low prevalence of the hepatitis B vaccine among brothel-based FSWs, with only 5.5% completing the recommended three doses. Key factors associated with vaccine uptake included spending more than four years in sex work,听prior screening for hepatitis B, flexible work schedules that allowed access to services, the presence of health-related outreach programs, and receiving hepatitis B-related information from peers. These findings have important implications for public health and practice. Screening programs should be leveraged as a gateway to provide hepatitis B education and vaccination, while outreach programs should be expanded to improve accessibility for hard-to-reach populations. Tailoring service delivery to accommodate nontraditional work hours and utilizing peer networks to disseminate information can further enhance vaccine uptake. Policymakers and healthcare providers must prioritize integrated, accessible, and peer-driven approaches to address the significant vaccination gaps in this high-risk group, ultimately reducing hepatitis B transmission and improving health outcomes.

Limitations of the study

This study has several limitations. First, vaccination status was assessed based on self-reports rather than antibody to hepatitis B surface antigen (anti-HBs) testing, which may have introduced recall bias or inaccurate reporting of vaccination history. Consequently, the proportion of individuals considered fully protected might differ if anti-HBs levels were used for assessment. Additionally, the findings may be affected by social desirability bias, as FSWs could have been inclined to report favorable vaccination behaviors. Being a cross-sectional study, the design only permits the identification of associations rather than causal relationships between factors and vaccination status. Furthermore, the findings may not be generalizable to all FSWs in Uganda due to the study鈥檚 focus on FSWs in Kampala, a more cosmopolitan district with potentially greater exposure to health information compared to upcountry areas.