We conducted a scoping review to identify barriers and facilitators influencing access and uptake of the COVID-19 vaccine in the DRC. This exploratory review was carried out following the analytical framework of Arksey and O'Malley (18). Arksey and O'Malley developed a five-step methodological model to guide researchers in conducting exploratory analyses. The following five-step model is proposed: (1) identification of research questions; (2) search for relevant studies; (3) study selection; (4) charting data; and (5) gathering, summarizing, and reporting the results (18).

A systematic search was conducted across three electronic databases—PubMed, ProQuest, and Scopus—covering publications from January 2019 to October 2023. We also performed a manual search of reference lists using Google Scholar, including sources in both English and French.

To enhance transparency and reproducibility the following search terms and Boolean operators were used: (“COVID-19 vaccine” OR “COVID-19 vaccination”) AND (“Democratic Republic of Congo” OR “DRC”) AND (“vaccine hesitancy” OR “Vaccine acceptance” OR “equitable access” OR “barriers to access” OR “vaccine uptake” OR “vaccination strategies”).

The inclusion criteria were peer-reviewed articles reporting on COVID-19 vaccine acceptance, hesitancy, access, or uptake; cross-sectional or other observational studies (case controls or cohort); quantitative, qualitative, or mixed studies; and a publishing date between January 2019 and October 2023.

We excluded studies without full text access as well as articles with insufficient data for extraction, editorials, letters, opinion pieces, and publications from predatory journals.

We extracted data using a standardized Microsoft Excel sheet, capturing the following variables: author(s), year of publication, study setting, data collection period, study design, population characteristics, sample size, and key findings related to vaccine access and hesitancy.

Due to the diversity of studies, a narrative synthesis approach was used to collect, synthesize, and map the literature (19). The following categories were used to classify the studies: (1) patterns of access and use of COVID-19 vaccines in the DRC, (2) barriers to equitable and timely vaccine access and uptake, and (3) strategies to address vaccine hesitancy, particularly among vulnerable populations.

Two authors independently assessed the quality of the studies included in the review. The Joanna Briggs Institute (JBI) Quality Assessment Tool was used to assess the quality of this study (20, 21). Qualitative assessment criteria were developed with parameters ranging from low quality (<49%) to medium (50%–79%) and high quality (80%–100%) for studies that analyze trends and barriers aimed at improving equitable and timely access to and use of COVID-19 vaccines in the DRC. While no studies were excluded based on quality, the appraisal informed our interpretation of the evidence. Higher-quality studies were given greater weight in the narrative synthesis, particularly when identifying key barriers and facilitators. Lower-quality studies were included but interpreted with caution, and their limitations were noted in the discussion (19).

In the initial search, 430 articles were identified from searches on the databases PubMed (n = 108), Scopus (n = 71), and ProQuest (n = 251). We used EndNote and removed around 255 duplicate articles. After removing duplicates, 175 articles were screened by titles and abstracts using the Rayyan software. In total, 160 articles were excluded due to irrelevant topics, failure to meet the inclusion criteria, and absence of an abstract or summary of the study. Fifteen (n = 15) studies remained for the full-text assessment for eligibility; of them, eight full-text articles were excluded (n = 9) because they did not meet the inclusion criteria, resulting in six published articles for the final analysis (n = 6), as illustrated by the PRISMA flow diagram in Figure 1.

All six studies employed quantitative methods: Five studies used a cross-sectional design (17, 22–25) and one used a cohort design (26). Sample sizes ranged from 348 to 1,195 participants. All studies were conducted in urban or semi-urban (rural) settings within the DRC and focused on vaccine acceptance, hesitancy, or access (Table 1).

Five studies reported on the willingness of Congolese individuals to receive the COVID-19 vaccine (17, 22–25). This willingness varied from 27.7% to 55.9%, with the highest acceptance reported by Ditekemena et al. (55.9%). Two studies also reported refusal rates: 44.1% in Ditekemena et al. and 72.3% in Kabamba et al. (17, 23) as shown in Figure 2.

Three key barriers emerged across studies: -

Fear of side effects: This was reported by 83.3% of respondents in the study by Mashako et al. and 84.4% of respondents in the study by Ditekemena et al. (22).

Several factors were associated with an increased likelihood of receiving the vaccination: -

Family history of vaccination: Individuals with vaccinated family members were more likely to accept the vaccine.

Two studies identified sociodemographic factors influencing vaccine uptake: -

Healthcare profession: Doctors and nurses were significantly more likely to accept vaccination (22, 23).

Five studies reported on vaccine willingness among the Congolese populations, with rates ranging from 27.7% to 55.9%. Despite the expressed willingness to be vaccinated against the COVID-19 virus, only 2.7% of the Congolese population was completely vaccinated at the time of data collection (3).

These figures contrast sharply with neighboring and regional countries. For instance, Kenya reported a willingness rate of 95.1% (27), Nigeria between 50.2% and 80.9% (28, 29), and Zimbabwe reported 55.7% (30). Ethiopia, however, showed a similarly low rate of 29.2% (31).

Significantly, most DRC studies focused on healthcare workers, who tend to have higher vaccine acceptance than the general population. A study in Guinea found that 65% of healthcare workers were vaccinated compared to 31% of the general population (32). This suggests that vaccine willingness in the broader Congolese population may be even lower than reported.

Facilitators of vaccine uptake in DRC included family history of vaccination, perceived susceptibility to the COVID-19 virus, fear of infection, belief in the existence of COVID-19, and awareness of vaccination strategies and priority groups.

Sociodemographic factors such as being a physician, nurse, or male healthcare worker, and having higher education levels were also associated with increased acceptance (22, 26). This situation can be attributed to increased knowledge of the COVID-19 disease and its vaccine. These findings align with the results of studies in Ghana and Italy, where education, perceived risk, and social influence (e.g., seeing others receive vaccination) were key motivators (33, 34).

Barriers to vaccination in the DRC were consistent across studies: (i) fear of side effects (reported by over 80% of respondents), (ii) mistrust in vaccine safety and efficacy, (iii) concerns about the vaccine being new or experimental, and (iv) limited public confidence in health authorities (17, 24, 25).

Since the end of our review period (2019–2023), several studies published in 2024–2025 have confirmed the persistence of previously identified barriers to COVID-19 vaccination uptake in the DRC, including distrust in health authorities and the vaccine, female gender, doubts about the effectiveness of the vaccine, and fear of side effects (35–40)

Similar concerns were reported in Ethiopia (hesitancy rate: 70.8%) (31) and Tanzania (63.3%) (27). Ackah et al. highlighted misinformation, media contradictions, and pharmaceutical shortages as additional barriers (41). Fernández-Sánchez et al. emphasized mistrust and limited trust among the migrant population (42).

In the DRC, vaccine hesitancy was further exacerbated by rumors, misinformation, and a lack of transparent communication during the early stages of the vaccination campaign. Toure et al. reported that in Guinea, distrust in the government was a major barrier to vaccine uptake (32).

To contextualize these findings, vaccine hesitancy in the DRC can be interpreted through the lens of the Health Belief Model (HBM) and Trust Theory. The HBM states that individuals are more likely to engage in health behaviors (e.g., vaccination) when they perceive a threat, believe in the efficacy of the intervention, and feel confident in their ability to act. In the DRC, low perceived threat, doubts about vaccine efficacy, and limited trust in health systems undermine these conditions.

Trust Theory further explains how institutional trust, particularly in government and health authorities, shapes public compliance. In contexts where trust is fragile or eroded by misinformation, vaccine campaigns face significant resistance. This underscores the need for transparent communication, community engagement, and culturally sensitive messaging to rebuild trust and improve vaccine uptake.

This scoping review was limited by the small number of eligible studies (n = 6), which may affect the generalizability of findings. Most studies involved in this review focused on health workers, potentially overlooking perspectives from the general population. Furthermore, the reliance on cross-sectional designs limits causal interpretation. These constraints highlight the need for more diverse and longitudinal research to inform equitable vaccine strategies in the DRC.