The Coronavirus disease 2019 (COVID-19) has brought about unprecedented challenges globally, threatening to undo the decades of progress in health systems, education and poverty eradication (1). To date, the pandemic has resulted in more than 6.9 million deaths, loss of jobs equivalent to 114 million, and about half of 3.3 billion workforce is on the verge of losing their livelihoods globally, thus raising concern regarding the appropriate responses (2, 3).

Countries around the globe have taken measures such as mass vaccination, wearing of masks, and setting up vaccination centers and handwashing stations in public places to control the pandemic (4–7). Whilst there has been a significant decline in new infections, a vaccine against COVID-19 is widely viewed as the safest health strategy to protect the public against transmission of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) (8, 9). The COVID-19 vaccines have been associated with a tremendous efficacy ranging between 50 to 90% and almost 100% protection from loss of life where one article determined the vaccine efficacy based on the prevention of symptomatic laboratory-confirmed COVID-19 in individuals without evidence of previous SARS-CoV-2 infection (9) while another determined the vaccine efficacy based on the reduction in the risk of COVID-19 cases among individuals who received the vaccine compared to those who received a placebo (8). As such, considerable investments in the manufacturing and rollout of these vaccines for emergency use have added a huge boost to the fight against COVID-19.

Equally, hand hygiene practices such as handwashing continue to be a critical strategy in reducing the transmission of SARS-CoV-2 and other related respiratory viruses. The World Health Organization (WHO) notes that handwashing with soap and water is the most effective low-cost strategy to minimize the transmission of SARS-CoV-2. Studies have shown that hand hygiene, when used effectively, can decrease transmission of other respiratory infections during the COVID-19 pandemic (10).

Given the importance of COVID-19 vaccines and handwashing, several studies have been carried out to determine the barriers and enablers to the uptake of vaccines and handwashing. In a study to assess hand hygiene compliance in India, it was indicated that spreading out facilities with clean water, soap, basins, and hand rub enhanced handwashing practices (10). Further, an assessment of hand hygiene practices among health care workers in Riyadh, Saudi Arabia, showed that the participants who had formal hand hygiene instruction used it regularly throughout the COVID-19 pandemic (11). Investigation of the obstacles to hand hygiene practices in sub-Saharan Africa revealed that to improve hand hygiene practices, it was necessary to offer education on the topic and sustainable solutions to the water shortage, disinfectants, and incentives, among other remedies (12). In addition to synthesizing factors influencing vaccine uptake and handwashing practices in Kenya, Tanzania, and Uganda, it is essential to acknowledge the diverse socio-economic landscapes, particularly in rural areas. Internet access in these regions plays a crucial role in disseminating health information, including guidance on vaccination and hygiene practices. The current situation in rural areas varies, with challenges such as limited access to social media information (13).

Evidence-based tactics in overcoming vaccine reluctance among Americans revealed that partnership between policymakers and the community was crucial in reducing vaccination hesitancy (14). The usage of public health surveillance systems to collect and process data could provide timely and accurate health information for dissemination and decision-making, such as vaccine distribution (14). In addition, community participation in vaccine distribution boosts vaccine uptake in an African setting, depicting the important role of cross-sector cooperation in helping people to access vaccines (15).

On the contrary, lack of trust in COVID-19 vaccines has resulted in vaccine reluctance (14). Despite the prior development of mRNA-based vaccines for relatively niche diseases, their application on a massive scale during the COVID-19 pandemic marked a paradigm shift. The relatively swift deployment of this advanced technology, coupled with the unprecedented challenges posed by intensive and uncontrolled internet coverage, introduced new complexities. The use of mRNA-based vaccines, previously reserved for specific diseases, now faced both accelerated implementation and widespread dissemination of information, including misinformation. Other causes of low uptake of COVID-19 vaccines include fear of needles or blood, safety worries and religious philosophical convictions. Most of these factors resulted from false information and misunderstandings (16). Despite several studies examining the enablers and barriers to COVID-19 vaccination and hand hygiene practices in different countries, the uptake of COVID-19 vaccines and handwashing practices is low in some countries. This situation threatens to undermine the future successes of immunization campaigns. This can be a challenge in building herd immunity. Handwashing habits and the East African region have received noticeably less attention in reviews that have been published thus far, which have mostly concentrated on factors impacting the intention and uptake of COVID-19 vaccines on the African Continent (17). The urgent need to recognize, understand, and deal with the distinct social, economic, and healthcare contexts that exist in Kenya, Uganda, and Tanzania is what motivated this comprehensive study. These environments have a significant impact on health-related behaviors, especially vaccination uptake and handwashing habits. The complex interactions between various socio-cultural elements, such as religious convictions, community institutions, and cultural traditions, shape how the public views and accepts health initiatives. Economic factors influence people’s ability to take preventive health practices and contribute to varying access to healthcare resources. Vaccine availability and the spread of health information are highly dependent on the state of healthcare systems, from infrastructure to health education programs. Furthermore, the distinct epidemiological terrain, political intricacies, and geographical heterogeneity introduce further facets of intricacy to health-associated decision-making within these areas. Therefore, developing targeted and culturally aware public health initiatives that can successfully promote immunization and hygiene behaviors within each nation requires an in-depth comprehension of these complex circumstances. Therefore, this review aimed at bridging the existing knowledge gaps, guiding the development of tailored public health interventions, and advancing the global understanding by offering context-specific insights by systematically reviewing and synthesizing existing evidence on the enablers and barriers of vaccine uptake and handwashing practices in the context of COVID-19 in Kenya, Uganda, and Tanzania. Our selection of these three countries as focus areas for the systematic review was deliberate and grounded in practical considerations. Conducting a systematic review focusing on Kenya, Uganda, and Tanzania is justified by the need to comprehensively understand the regional dynamics influencing COVID-19 vaccine uptake and handwashing practices within the East African context. Studies such as those by Nabukeera (18) and Davis et al. (19) emphasize the variability in healthcare systems across regions, highlighting the importance of examining the unique challenges and strengths within the healthcare systems of these specific countries. Furthermore, research by Abubakar et al. (20) and Bakeera et al. (21) underscores the significance of cultural and socio-economic factors in shaping public health behaviors, necessitating an examination of local contexts and cultural nuances. Additionally, studies by Briceno et al. (22) and Muchangi et al. (23) highlight the importance of considering epidemiological heterogeneity when designing interventions, emphasizing the need to assess the specific epidemiological factors influencing vaccine uptake and handwashing practices in this region. Thus, a focused review of Kenya, Uganda, and Tanzania provides valuable insights into addressing the pandemic within the East African context, enabling tailored interventions and policy recommendations to tackle COVID-19 effectively. Furthermore, it informs actionable strategies that contribute significantly to broader preparedness and responses to infectious disease outbreaks in the region.

This systematic review aimed to synthesize evidence on enablers and barriers to vaccine uptake and handwashing practice in Kenya, Uganda, and Tanzania to prevent and control COVID-19. Our results acknowledge that access to vaccines, hand hygiene programs and availability of water are crucial in promoting vaccine uptake and handwashing behavior among individuals. On the contrary, lack of awareness about vaccines and handwashing facilities, inaccessibility of vaccines and handwashing resources hinder the effective use of the vaccine and washing of hands.

Our findings are similar to previous studies, which indicated that providing facilities with clean water, soap, basins, and hand rub increased handwashing practice (45). Similarly, previous research on access to knowledge and information about hand hygiene and COVID-19 vaccines has presented similar findings (11). The author’s findings revealed that participants who had received formal hand hygiene training applied the practice routinely during the COVID-19 pandemic. Our results are consistent with the conclusion by Alegbeleye and colleagues that improving hand hygiene practices requires providing education on hand hygiene practices (12). These findings emphasize the importance of community leaders’ involvement as supported by previous research showing that collaboration between community leaders and governments improved the rates of vaccination (14). In addition, community involvement in vaccine delivery has been found to increase vaccine uptake (15). This may be attributed to their familiarity with the community dynamics and ability to communicate effectively in the local language, a critical factor in rural areas where COVID-19 vaccine information must be conveyed in the native tongue. This challenge was effectively addressed by capitalizing on existing community structures, such as baraza gatherings, which are deeply ingrained in the East African context (46). These gatherings serve as invaluable platforms for sensitizing rural communities in their local dialects about the importance of COVID-19 vaccines. This approach is corroborated by qualitative research findings, where a rural community in a high-income country adopted a multifaceted approach. This included translating vaccine information into the local dialect on posters, leveraging local radio broadcasts, and mobilizing community champions to bolster vaccine confidence (47).

In concordance with our findings, studies have shown that access to knowledge and information about the importance of vaccination, the benefits, the side effects, and the risks have helped people to make informed vaccination decisions (48, 49). In particular, Bongomin et al. reported that 70.1% of respondents were willing to be vaccinated due to increased sensitization. A review focusing on low and middle-income countries (LMICs), including Uganda, noted that due to awareness focusing on topics such as vaccine efficacy and safety (49).

Regarding barriers to the COVID-19 vaccine uptake and handwashing practice, the study findings agree with previously published evidence. Assessment of hand hygiene barriers in a teaching hospital’s intensive care unit in southeast Iran found that lack of quality equipment reduced hand hygiene practices (50). Further, insufficient quality equipment as evidenced by poor quality soap was associated with skin dryness and itching and a shortage of disinfectants led to minimal hand hygiene compliance (50). Another study in Indonesia revealed that limited water led to poor handwashing practices (10). Additionally, our findings align with a review that identified infrastructural deficits, such as a lack of water and soap, as barriers to hand hygiene practices (51). Notably, our synthesis resonates with findings from Naidoo’s review, which highlighted widespread fears over potential side effects and concerns about the newly developed COVID-19 vaccine being perceived as unsafe for the African population (17). Similarly, our results parallel Naidoo’s observation that a substantial number of studies across different contexts expressed concerns regarding the vaccine’s perceived ineffectiveness in providing protection against COVID-19 (17).

Safety concerns, misinformation, and a lack of trust in the government have influenced the low uptake of vaccines. Previous research has reported similar findings. Rutten and colleagues highlighted that a lack of trust in COVID-19 vaccines resulted in vaccine reluctance (14). Similarly, the rapid pace of vaccine development and rampant misinformation in social media has hindered successful vaccine uptake. A study exploring COVID-19 vaccine hesitancy revealed that fear of needles or blood, safety concerns, costs, and religious beliefs had led to low vaccine uptake (16).

In addition to the distinctive factors highlighted in our narrative synthesis regarding vaccine uptake and handwashing practices in East African countries, it is noteworthy to draw parallels with results from high-income countries, such as Portugal. Low confidence in the COVID-19 vaccines being developed and the perception that the information provided by health authorities during the pandemic was inconsistent and contradictory were identified as barriers to vaccine uptake (52), potentially fueled by the rapid development of COVID-19 vaccines amid the urgency of the pandemic. However, it is crucial to acknowledge that high-income countries often demonstrated a higher level of preparedness in terms of healthcare infrastructure and vaccine programs, compared to lower-middle-income countries (LMICs) like those in East Africa.

Our narrative synthesis highlights the challenges faced by LMICs, including limited funding for COVID-19 vaccine programs and hand hygiene practices, which posed significant barriers. Unlike high-income countries with more extensive resources, LMICs grappled with constrained healthcare budgets and infrastructural deficits, amplifying the difficulties in implementing effective health interventions. Recognizing these disparities prompts a call for more extensive and meticulous post-pandemic research to comprehensively understand our systems’ complexities during the crisis. Such research will be instrumental in identifying the flaws in our preparedness, informing targeted strategies for future health crises, and ensuring the equitable distribution of resources for effective public health interventions. Furthermore, we advocate for future interventions that prioritize education and early engagement of local community leaders. Tailoring educational campaigns to the socio-cultural contexts of Kenya, Uganda, and Tanzania and involving community leaders from the outset is crucial for enhancing the effectiveness of initiatives promoting vaccine uptake and handwashing practices. Proactive community involvement fosters trust, heightens awareness, and contributes to the successful adoption of health practices.

Our study is the first systematic review focusing on the enablers and barriers to COVID-19 vaccine uptake and handwashing to prevent and control COVID-19 in East Africa. This review can be used as a baseline for similar research within this region. However, we acknowledge that the study was limited to three nations; hence our findings may not be generalizable to other regions due to varying political, environmental, economic, and social factors. Additionally, we acknowledge limitations in the search for relevant literature due to accessibility issues, noting the search was limited to three databases: PubMed, ScienceDirect, and Google Scholar. PubMed was chosen for its comprehensive coverage of biomedical literature, including COVID-19-related research (53, 54). ScienceDirect offers diverse scientific journals (55), while Google Scholar enhances comprehensiveness by covering both peer-reviewed and non-peer-reviewed sources. Despite valuable databases like Web of Science and Scopus being inaccessible due to subscription requirements, the focus on freely accessible databases aimed to optimize efficiency and transparency. While acknowledging the potential for missed literature, the team mitigated this by rigorously screening studies based on predefined criteria.

This study contributes to the understanding of the factors affecting COVID-19 vaccine uptake and handwashing behavior in Kenya, Uganda and Tanzania. Among the enablers of vaccine uptake and handwashing practice are the accessibility of vaccines. soap and water, and the involvement of local leaders. Conversely, lack of awareness and fear of side effects hinders individuals from taking the COVID-19 vaccine and practicing effective handwashing. Our systematic review points to the need for a more extensive scope of research to increase the generalizability of the study findings.

The original contributions presented in the study are included in the article/Supplementary material, further inquiries can be directed to the corresponding author.

JMM: Conceptualization, Data curation, Formal analysis, Investigation, Methodology, Project administration, Supervision, Validation, Visualization, Writing – original draft, Writing – review & editing. JM: Methodology, Validation, Visualization, Writing – review & editing. HM: Data curation, Methodology, Writing – review & editing. KK: Data curation, Methodology, Writing – review & editing. SK: Data curation, Methodology, Writing – review & editing. LK: Data curation, Methodology, Writing – review & editing. RM: Data curation, Methodology, Writing – review & editing. MN: Data curation, Writing – review & editing.