key: cord-0302243-2wohde2j
authors: Ba, M. F.; Faye, A.; Kane, B.; Diallo, A. I.; Junot, A.; Gaye, I.; Bonnet, E.; Ridde, V.
title: Factors associated with COVID-19 vaccine hesitancy in Senegal: a mixed study
date: 2021-12-21
journal: nan
DOI: 10.1101/2021.12.20.21267724
sha: 3a9459aff6078b2fdbec75cf9a0d439d49e67cb7
doc_id: 302243
cord_uid: 2wohde2j

Introduction: The most effective way to control the COVID-19 pandemic in the long term is through vaccination. Two of the important components that can hinder it are vaccine hesitancy and vaccine refusal. This study, conducted before the arrival of the vaccines in Senegal, aims to assess and identify factors associated with hesitancy to the COVID-19 vaccine. Methods: This study was an explanatory, sequential, mixed-methods design. We collected quantitative data from December 24, 2020, to January 16, 2021, and qualitative data from February 19 to March 30, 2021. We conducted a marginal quota sampling nationwide. We used a structured questionnaire to collect data for the quantitative phase and an interview guide with a telephone interview for the qualitative phase. We performed descriptive, bivariate, and multivariate analyses with R software version 4.0.5 for the quantitative phase; and performed manual content analyses for the qualitative phase. Results: We surveyed 607 people for the quantitative phase, and interviewed 30 people for the qualitative phase. Individuals who hesitated or refused to be vaccinated represented 12.9% and 32.8%, respectively. Vaccine hesitancy was related to gender, living in large cities, having a poor attitude towards the vaccine, thinking that the vaccine would not help protect them from the virus, being influenced by people important to them, and lacking information from health professionals. Vaccine refusal was related to living in large cities, having a poor attitude towards the vaccine, thinking that the vaccine would not help protect them from the virus, thinking that the vaccine could endanger their health, trusting opinions of people who were important to them, and lacking information from health professionals. Conclusion: The results of the study show that the factors associated with hesitancy and refusal to be vaccinated against COVID-19 are diverse and complex. Reducing them will help to ensure better vaccination coverage if the current challenges of vaccine accessibility are addressed. Therefore, governments and health authorities should intensify their efforts to promote vaccine confidence and reduce misinformation. Keywords: Vaccine hesitancy, COVID-19, Mixed method, Senegal

Coronavirus disease 2019 (COVID-19) remains a significant public health concern. Although much effort has been devoted to implementing control strategies-including travel bans, isolation of confirmed cases and contacts, social distancing, and hygiene measures-virus transmission is likely to rebound when these strategies are lifted [1] . Among multiple possible strategies, one way to control this pandemic is through mass vaccination [2] . Achieving effective results from vaccination depends not only on accessibility, which remains a major challenge in Africa, but also on the acceptance and willingness of the population to be vaccinated. [3] . Thus, one of the major obstacles to achieving high immunization coverage is vaccine hesitancy [4] . Beyond the long-standing debates on the concept and its scope [5] , the World Health Organization (WHO) defines vaccine hesitancy as the delay in acceptance or refusal of vaccination despite the availability of immunization services [6] .

Worldwide, studies show very high variability in acceptability of the COVID-19 vaccine, with rates ranging from 29.4% to 86.0%. [7] [8] [9] [10] [11] [12] [13] . In the majority of studies of the public stratified by country, acceptance of COVID-19 vaccination showed a level ≥ 70% [14] . A survey of 15 African countries showed that approximately 80% of people are willing to accept the COVID-19 vaccine once it is available and is considered safe and effective. Although the overall results are encouraging, there are significant regional differences in Africa [15] . A meta-analysis showed that the proportion of individuals reporting that they would refuse a COVID-19 vaccine was 14.3% [95% CI: 11.4% to 17.9%], and the proportion reporting uncertainty was 22.1% [95% CI: 17.8% to 27 .1%]. [16] . The latter also showed that intentions to vaccinate have decreased over time while refusals have increased [16] . Several factors can influence acceptance or refusal of the vaccine (professional status, politics, gender, age, education, income, etc.). [17] . In addition, the novelty of the disease, concerns about the safety and efficacy of the vaccine, and distrust of governments have resulted in a significant proportion of people indicating a reluctance to be vaccinated against COVID-19 [17] .

Senegal launched its vaccination campaign against COVID-19 on 23 February 2021. As of December 2, 2021, 1,328,633 people have received at least one dose, including 924,182 people who have received two doses, representing a complete coverage of 5.5% of the total population. [18] . This coverage is far from the objective set by the authorities, which was to ensure vaccination of at least 20% of the general population before June 2021 [19] . One of the important components of this challenge, despite its multifaceted nature, is vaccine hesitancy and refusal. Thus, assessing its scope and magnitude is necessary to guide interventions to . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint

The copyright holder for this this version posted December 21, 2021. ; https://doi.org/10.1101/2021. 12.20.21267724 doi: medRxiv preprint build and sustain responses to this epidemic. Understanding and responding to the determinants is necessary to achieve a high vaccine coverage.

This study aims to assess and identify factors associated with hesitancy towards the COVID-19 vaccine in Senegal.

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint 

This study is a sequential, explanatory, mixed-methods design where qualitative data should help understand the results of the analysis of the previously collected quantitative data [20] .

The writing of the article followed the quality criteria proposed by the Mixed Methods Appraisal Tool [21] . The quantitative data were collected from December 24, 2020, to January 16, 2021, before the vaccine campaign; and the qualitative data were collected during the vaccine campaign -from February 19 to March 30, 2021.

The study population consisted of individuals from the general population living in Senegal aged 18 years and older with a mobile phone number. In June 2020, we conducted an initial nationwide telephone survey of 813 people to measure the social acceptability of governmental measures to control COVID-19 [22] . The study used a marginal quota sampling strategy [23] . In order to have a representative sample of the population, we carried out a stratification according to the weight of the population by region, gender, and age group.

Based on this first survey, which did not concern the vaccination aspects, we organized a second survey among these same people. The final quantitative sample size was 607 (74.6%).

A comparison of the characteristics of the quotas chosen to constitute the sample between the two surveys shows that while they are not statistically different for region (p=0.99) or age (p=0.08), they are for gender (p=0.04).

The qualitative sample was composed of 30 individuals selected from those who said they were reluctant (n=15) or unwilling (n=15) to be vaccinated, nested within the final quantitative sample (n=607) (Appendix 1). The selection of these 30 individuals followed the same stratification as the quantitative sample to have diverse views. These individuals were drawn at random from the quantitative sample and according to this stratification. Individuals were replaced when they refused to participate or could not be reached.

The quantitative data collection tool was a structured and closed questionnaire. Five female interviewers speaking six languages (French, Diola, Wolof, Sérére, Pulaar, Soninké) collected the data. The survey was conducted by telephone. The interviewers used tablets equipped with an Open Data Kit (ODK) software to administer the questionnaire [24] . We performed data quality control by training interviewers, pre-testing the tools, scanning the questionnaire, . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint

The copyright holder for this this version posted December 21, 2021. ; https://doi.org/10.1101/2021.12.20.21267724 doi: medRxiv preprint collecting the data on a tablet, and recruiting a supervisor to monitor data collection in realtime daily.

Intention to be vaccinated, the dependent variable, was measured with a 5-point Likert scale (strongly agree = 5 to strongly disagree = 1). Following the WHO definition, it was transformed into a 3-mode variable: -Strongly agree and agree = intention to be vaccinated -Neither agree nor disagree = reluctant to get vaccinated -Disagree and strongly disagree = refusal to be vaccinated

The independent variables collected in the quantitative survey were conceptualized according to the WHO vaccine hesitancy model [6] . It concerned: The independent variables composed in the form of a 5-point Likert scale were transformed into binary variables (Yes = Strongly agree and agree; No = Other). For the variable "Confidence in the government in the fight against COVID-19," which was in the form of a score ranging from 0 to 10, the person was considered to have had complete confidence when he/she had the maximum score. Using principal component analysis (PCA), we obtained the wealth quintile on durable asset ownership and housing characteristics. This approach ranked individuals from the poorest (1) to the least poor (5) to capture the socio-economic differences.

All this made it possible to determine the level of refusal and reluctance to be vaccinated and to identify the factors associated with them.

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint

The copyright holder for this this version posted December 21, 2021. ; https://doi.org/10.1101/2021.12.20.21267724 doi: medRxiv preprint

The qualitative survey was guided by the results of the quantitative analyses by seeking to understand more deeply the reasons for hesitation or refusal. Using an open-ended guide, individual interviews were conducted over the telephone for an average of 30 minutes.

We performed quantitative analyses with R software version 4.0.5. Categorical variables were described by numbers and percentages. We used the Chi2 test to compare proportions with a 5% alpha risk. We modelled vaccine hesitancy and refusal using multinomial logistic regression in the multivariate analysis. We included all variables with p-values less than 0.25 in the bivariate analysis in the initial model [25] . To construct the final model, we used the stepwise top-down selection procedure in each model. We individually removed variables that did not improve the model [26] . We used the likelihood ratio test to compare the nested models [26] . We used this multivariate analysis to determine adjusted Odds Ratios and estimated the corresponding 95% confidence intervals (CIs) for all variables.

For the qualitative data, we transcribed the interviews in full in French. Then, we performed a manual content analysis [27] . According to the mixed methods approach, divergences and convergences are highlighted in the presentation of the results [28] . Explanatory elements for vaccine refusal or hesitation that were not considered in the quantitative survey emerged in the qualitative survey.

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint

The copyright holder for this this version posted December 21, 2021. ;

In the study, 67.1% of the individuals were between 25 and 59 years of age. Males accounted for 60.3%. The proportion of respondents with no education was 41.7% (Appendix 2).

Individuals who hesitated and refused to be vaccinated were 12.9% and 32.8%, respectively 

The proportion of vaccine-hesitant among those who thought it was not useful to be vaccinated was 23.3%. This proportion was 9.0% among those who thought it was useful (p<0.001). The proportion of individuals who refused to be vaccinated because the vaccine could endanger their health was higher than the proportion who said the vaccine would not endanger their health (67.9% vs 22.8%, p<0.001) (Appendix 3). . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint 

Hesitancy and refusal to be vaccinated were quantitatively related to the failure of health workers to provide appropriate and necessary information and support for vaccination (Table   1) This communication by health professionals is very important because it will reassure the population for a better success of the vaccination campaigns: "The day I am reassured, I will vaccinate myself" (Female, hesitant).

The quality of information was also highlighted in the qualitative interviews, and the conspiracy theories were prominent: "The day before yesterday, I was shown someone who works in this field explaining that the vaccines sent to Africa are not the best and that they carry undesirable risks" (Male, refusal). Some even went so far as to question whether the vaccine received by the state authorities is the same as the one that the population will use: "There is no proof that the vaccine received by the health authorities and the state authorities is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. 

The international public health and economic impact of COVID-19 has prompted private and governmental organizations to work together to address the pandemic. Significant investments have been made in developing vaccines against COVID-19 [29] . Nevertheless, hesitation in addition of accessibility about the COVID-19 vaccine may limit global efforts to control the pandemic and its adverse health and socioeconomic effects. [14] . Our study showed that 12.9% of individuals hesitate to be vaccinated, and 32.8% would not take the vaccine when it became available in Senegal. These results are similar to those of a study conducted in New

Zealand and those of a systematic review and meta-analysis including 13 countries [16, 30] .

However, compared to these studies conducted in the USA, Portugal, and Great Britain, the proportion of refusals is higher in our study [4, 16, [30] [31] [32] . This result is even more worrying as the systematic review and meta-analysis of Robinson et al. [16] showed that the percentages of vaccine refusals and hesitation increased as the pandemic progressed. This situation could be confirmed by the disposal of thousands of doses of expired COVID-19

vaccine in October 2021 because the number of people vaccinated is quite small [18] .

Vaccine hesitancy was associated with female gender in our study in Senegal. This result is similar to those found in New Zealand, Israel, China, the UK, the USA, Qatar, and Portugal. [3, 4, 30, [32] [33] [34] . This disparity could be explained by the fact that women perceive a lower risk of the disease [3] . In addition, several reports and medias have shown higher risks of complications, infectiousness, and death from COVID-19 in men [35] . Therefore, women may be less likely to be affected by this disease. In addition, the finding in this study that women are more likely to show reluctance to be vaccinated is of concern as women play a central role in the vaccination of children.

Hesitancy and refusal to be vaccinated were related to living in large cities (Dakar, Thiès, and Diourbel). These same perceptions were noted in our previous study, which showed that the more regions are affected by the pandemic, the less confidence respondents have in the government and the less effective they perceive the measures to be [22] . As of December 2, 2021, these three most populated regions of Senegal will account for more than 80% of the cases of COVID-19 in the entire country [18] . One might have thought that vaccination intentions would be greater in these areas because of the burden of the pandemic. However, these results could be explained by the belief in a certain natural immunity, by a greater exposure to misinformation encountered on social networks, or by their higher standard of . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The study showed that a bad attitude (thinking that it was not desirable and important to be vaccinated) towards vaccination was linked to hesitating and refusing vaccination. This poor attitude was mainly explained in the qualitative survey by rumours circulating-particularly on social networks-about the vaccine and the length of time it took to manufacture it. These reasons were consistent with the findings of several studies [3, 17, 36] . One report showed that the main topics of conversation related to vaccine hesitancy on Facebook and Twitter included posts about "dropouts," people not showing up for their second injection, and parents resisting vaccinating their children "because of the low risk of COVID infection in their home." [37] . Not surprisingly, there is a growing focus on the role of the media and in particular social media in shaping public opinion around COVID-19 and the vaccine. Social media, with its instant communication and access to a large audience, when combined with the ability to express oneself anonymously, offers immense potential for the spread of unverified and uncontrolled information. [34] . Public health organizations, health professionals, and media platforms should collaborate to ensure the accuracy of information, provide programs to improve health literacy levels to enable the target population to make an informed decision. Furthermore, the impact of these actions implies that strategies to overcome hesitancy can be framed in models that take into account these multi-faceted and multi-level factors [3] .

The fact that individuals thought that vaccination would not help protect them from the virus was associated with reluctance and refusal to be vaccinated. Also, individuals who thought that the coronavirus vaccine might put their health at risk were more likely to refuse the vaccine. Indeed, several studies show that concerns about vaccine safety and efficacy appear to be important in vaccine intention [3, 4, 12, 17, 32, 34] . This concern transcends sociodemographic aspects and countries. This concern led to the fact that some respondents to the survey wanted to "wait and see" whether vaccination was safe before getting vaccinated.

Thus, effective communication about safety and efficacy, and greater transparency about vaccine development and distribution, including financial aspects, should be the cornerstone of all other strategies to ensure equitable mass immunization programs related to COVID-19 [38] [39] [40] .

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. The hesitancy and refusal to vaccinate was also related to the fact that individuals thought that most people important to them would not think they should be vaccinated against COVID -19, and that health workers do not provide the appropriate and necessary information and support for vaccination. Several studies have examined the role of these factors consistent with our study [40] [41] [42] [43] [44] [45] [46] [47] [48] [49] . Health professionals appeared to be a reliable source of information. Their recommendations [42, 46, 47, 49] and support from family and friends [43, 47] play an important role in influencing their perceptions and behaviours towards vaccination. These results suggest that health professionals (especially general practitioners and paediatricians) need to be better involved in vaccination campaigns to support people and help them make informed decisions.

This study is not without its limitations. It only involved people with mobile phones, thus excluding the most marginalized populations. In addition, the cross-sectional nature of the data limits our ability to draw conclusions about causal links. However, the sample is representative of the Senegalese population and the use of mixed methods allowed for a better understanding of the results and the organization of the arguments.

The results of the study show that the factors related to hesitation and refusal to be vaccinated against COVID-19 in Senegal are diverse and complex. Reducing them will help to ensure better vaccination coverage as antigens become available. Therefore, governments and health authorities should intensify their efforts to encourage vaccine confidence and reduce misinformation. However, continued monitoring of COVID-19 vaccine hesitancy and refusal in the coming months will be critical to adjusting measures to address vaccine hesitancy, thereby ensuring adequate uptake of the vaccine. Finally, the current situation in Africa shows that there are still many challenges to vaccine accessibility for which the international community must act urgently. In addition to acceptance, accessibility is the second phase of the vaccine coverage coin that should not be forgotten.

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint 

This research was conducted within the framework of the ARIACOV programme (Support for the African Response to the Covid-19 Epidemic), financed by the French Development Agency through the "COVID-19 -Health in Common" initiative.

The authors declare that they have no known financial conflicts of interest or personal relationships that might appear to influence the work reported in this article.

The study received approval from the National Health Research Ethics Committee of Senegal (SEN/20/23).

. CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint

The copyright holder for this this version posted December 21, 2021. ; https://doi.org/10.1101/2021.12.20.21267724 doi: medRxiv preprint

Evidence-Based Strategies for Clinical Organizations to Address COVID-19 Vaccine Hesitancy

Among Healthcare Workers in the Democratic Republic of the Congo

Factors Influencing Public Attitudes toward COVID-19 Vaccination: A Scoping Review Informed by the Socio-Ecological Model

Factors Associated with COVID-19 Vaccine Hesitancy

Review of Vaccinations. The myth of refusal by Laurence Monnais

Vaccine hesitancy: Definition, scope and determinants

An online survey of the attitude and willingness of Chinese adults to receive COVID-19 vaccination

COVID-19 Vaccination Intent, Perceptions, and Reasons for Not Vaccinating Among Groups Prioritized for Early Vaccination -United States

Acceptance of a COVID-19 Vaccine in Southeast Asia: A Cross-Sectional Study in Indonesia

Parents' and guardians' views on the acceptability of a future COVID-19 vaccine: A multi-methods study in England

High Rates of COVID-19 Vaccine Hesitancy and Its Association with Conspiracy Beliefs: A Study in Jordan and Kuwait among Other Arab Countries

COVID-19 Vaccine Hesitancy Worldwide: A Concise Systematic Review of Vaccine Acceptance Rates

Nnorom-Dike O. COVID-19 vaccine rollout: will it affect the rates of vaccine hesitancy in Africa? Public Health

International estimates of intended uptake and refusal of COVID-19 vaccines: A rapid systematic review and meta-analysis of large nationally representative samples

Vaccine hesitancy in the era of COVID-19

Centre des Opérations d'Urgence Sanitaire / Ministère de la Santé et de l'Action Sociale. Response to the COVID-19 pandemic in Senegal Situation Report No. 121 of 15

Ministry of Health and Social Action. National strategy for vaccination against COVID-19

How far is mixed methods research in the field of health policy and systems in Africa? A scoping review

Mixed Methods Appraisal Tool (MMAT), Version 2018. User guide. McGill

Acceptability of Government Measures Against Covid-19 Pandemic in Senegal: a Mixed Methods Study. Researchsquare

A theory of quota surveys. Survey Tech, Stat Canada

Participating in a vaccine trial for COVID-19 in Senegal: trust and information

Applied Logistic Regression

Model building strategy for logistic regression: Purposeful selection

Qualitative Data Analysis

Understanding divergence of quantitative and qualitative data (or results) in mixed methods studies

The COVID-19 Vaccine: Why the Hesitancy?

COVID-19 Vaccine Hesitancy and Acceptance in a Cohort of Diverse New Zealanders

COVID-19 vaccination intention in the UK: results from the COVID-19 vaccination acceptability study (CoVAccS), a nationally representative cross-sectional survey

COVID-19 Vaccination Hesitancy in the United States: A Rapid National Assessment

Vaccine hesitancy: the next challenge in the fight against COVID-19

COVID-19 vaccine hesitancy and attitudes in Qatar: A national cross-sectional survey of a migrant

Systematic Review and Meta-Analysis of Sex-Specific COVID-19 Clinical Outcomes

COVID-19 Vaccine Hesitancy and Its Associated Factors in Japan

Africa Infodemic Response Alliance. COVID-19 Infodemic Trends in the African Region

Vaccine confidence: the keys to restoring trust

The VACCINES Act: Deciphering Vaccine Hesitancy in the Time of COVID-19

A global survey of potential acceptance of a COVID-19 vaccine

An online survey of the attitude and willingness of Chinese adults to receive COVID-19 vaccination

Acceptance of COVID-19 Vaccination during the COVID-19 Pandemic in China

Examining Australian public perceptions and behaviors towards a future COVID-19 vaccine

Knowledge and Attitudes on Vaccination in Southern Romanians: A Cross-Sectional Questionnaire

As the Pandemic Progresses, How Does Willingness to Vaccinate against COVID-19 Evolve?

Acceptability of a COVID-19 vaccine among adults

It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprintThe copyright holder for this this version posted December 21, 2021 . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint . CC-BY-NC-ND 4.0 International license It is made available under a is the author/funder, who has granted medRxiv a license to display the preprint in perpetuity. (which was not certified by peer review) preprint