Participating in vaccine research for COVID-19 in Senegal: trust and information
Authors:
Valéry Ridde
a
,
✱
, Mouhamadou Faly Ba
b
, Ibrahima Gaye
b
, Amadou Ibra Diallo
b
,
Emmanuel Bonnet
c
, Adama Faye
b
a
CEPED, IRD-University of Paris, ERL INSERM SAGESUD, Paris, France; Institute of
Health and Development, Cheikh Anta Diop University, Dakar, Senegal
b
Institute of Health and Development, Cheikh Anta Diop University, Dakar, Senegal
c
IRD (French Institute for Research on Sustainable Development) IRD, UMR 215 Prodig,
Aubervilliers, France
✱
Corresponding author.
E-mail address: valery.ridde@ird.fr (V. Ridde)
Abstract
This research aims to understand the level and determinants of people's willingness to
participate in a vaccine trial for COVID-19 in Senegal. We conducted a telephone survey
among a marginal quota sample of 607 people over 18 years of age. Only 44.3% of the
participants wanted to participate in a vaccine trial for COVID-19, with females intending
to participate more than males. Participants who intended to be vaccinated against
COVID-19 (OR = 6.48, 95% CI [4.12-10.4]) and who thought that being infected with the
coronavirus would have a significant impact on their health (OR = 2.34, 95% CI [1.57,
3.51]) were more likely to agree to take part in the COVID-19 vaccine research. Confidence
in the vaccine, health personnel, and government in the fight against the pandemic are
key factors in intending to participate in vaccine research in Senegal.
Keywords: Vaccine; Research; Vaccine hesitancy; COVID-19; Senegal
1. Introduction
The arrival of the COVID-19 pandemic has not changed Africa’s collective imagination and
discourse on Africa as a medical and vaccine testing ground. Indeed, historians and other
social scientists have long documented how Africa has been the site of biomedical
research, whether for testing drugs or vaccines [1-5]. Social scientists have shown the
need for a complex and nuanced view beyond the ethical challenges and power issues
[2,4]. However, we are in the process of "globalizing human subjects research" [6] after
the scientific imperialism of the Pasteur Institutes [7].
In francophone Africa, particularly in Senegal, the COVID-19 pandemic has opened a new
window of opportunity for these debates. Contrary to what is imagined about infectious
diseases, after Ebola [8,9] or Lassa [10], Africa was neither the first continent to be affected
nor the one that, thus far, suffered the most consequences [11]. However, a televised
interview with two French doctors set off the "April Fool's prank" on April 1
st
, 2020 [12]. In
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NOTE: This preprint reports new research that has not been certified by peer review and should not be used to guide clinical practice.
a context where debates on the decolonisation of global health are numerous [13,14],
Africans hear these two Frenchmen say that it is necessary to test the BCG vaccine for
prevention in Africa against COVID-19. Academic reactions on the ethical issues this
raises and reactions in Africa’s (social) media will be numerous [12,15]. Rumours about
Africa as a vaccine testing ground will, from then on, continue to grow significantly [16]. At
the end of the 1970s in Senegal, the first vaccine trials against hepatitis B gave rise to
numerous ethical debates [3]. The 2007 meningitis vaccine trial also gave rise to numerous
controversies, showing the lack of journalist’s scientific culture and an attempt at political
instrumentalisation [17]. This story was brought back to the forefront by the national media
in April 2020 with the French doctors’ speech. Yet Africa is by far one of the continents
where biomedical research is least carried out, with COVID-19 being no exception [18]. A
May 2020 analysis shows that of the 1002 therapeutic clinical trials for COVID-19
worldwide, only 32 (3.2%) were conducted in Africa [19]. Of the hundreds of ongoing
vaccine trials against COVID-19, only 16 are taking place in Africa as of mid-March 2021
(South Africa: 11; Kenya = 3; Egypt 1; Morocco 1
1
).
However, like other continents [20], Africa needs to conduct research and trials to test
drugs and vaccines against COVID-19 [21]. Not only is this essential to adapt biomedical
products and vaccines to national contexts and populations, but countries now have
research centres and ethics committees competent to carry out these trials under good
ethical conditions [18]. Thus, in a context where vaccines are the common solution to fight
against the COVID-19 pandemic and other epidemics to come, it is important to
understand the willingness of Senegalese to participate in a vaccine trial. Qualitative
research in Senegal has shown that Senegalese people do not wish to be "exploited" by
such COVID-19 vaccine trials but noted an ambiguous relationship and significant
ignorance about how biomedical research works [22]. Thus, the objective of this article is
to understand the level and determinants of Senegal’s population's willingness to
participate in a COVID-19 vaccine trial.
2. Method
We conducted a cross-sectional, descriptive, and analytical study. We collected data from
December 24, 2020, to January 16, 2021. We carried out the study on a sample of 607
people aged over 18 years. We used the marginal quota sampling strategy [23] to have a
representative sample of the national population stratified by population weight by region,
gender, and age group. Five female interviewers speaking six languages (French, Diola,
Wolof, Sérére, Pulaar, Soninké) carried out data collection through a telephone survey.
We used tablets equipped with Open Data Kit (ODK) software to administer the
questionnaire.
The variables in our study were based on acceptability models [24,25]. They included
socio-demographic characteristics (age, gender, education, region of residence, wealth
tercile, chronic medical conditions), vaccination history, attitude towards the COVID-19
vaccine measured by five items in the form of a five-point Likert scale, intention to be
vaccinated against COVID-19, fear of the coronavirus, concern for serious health
1
https://covid19.trackvaccines.org/trials-vaccines-by-country/
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consequences if infected by the coronavirus, trust in the government to fight the COVID-
19 epidemic, willingness to participate in COVID-19 vaccine research, and reasons for
refusing or agreeing to participate in this research.
We used R software version 4.0.3 for data analysis. We described the quantitative
variables by the mean ± standard deviation and the qualitative variables by their
frequencies. Then, we used a Ch2 test to compare two qualitative variables and a student's
t test a qualitative and a quantitative variable. Finally, we used multivariate logistic
regression to determine the factors associated with the willingness of respondents to
participate in COVID-19 vaccine research. All variables with p-values less than 0.25 in the
comparisons were retained for the full model construction [26]. We used the stepwise top-
down selection procedure to build a more parsimonious reduced model [27]. Significance
was considered at a p-value < 0.05.
3. Results
Women represented 39.7% of the respondents. In our study, 15.5% of the respondents
reported having a chronic disease. The average confidence in the Senegalese government
in the fight against the epidemic was 6.6/10 ± 3.1. 54.4% of respondents expressed the
intention to be vaccinated. According to their statements, 44.3% of the participants would
like to participate in vaccine research for COVID-19 if it took place (Appendix 1). Of these,
23.0% (62/269) explained this because they trusted the health workers (Figure 1). Of those
who refused to participate in the research, 34.4% (116/337) expressed a lack of trust in
vaccines, and 29.4% (99/337) perceived a lack of safety of the vaccine research (Figure
2).
Figure 1: Reasons for willingness to participate in COVID-19 vaccine research (N=269)
0,37
0,37
1,86
2,60
5,20
5,58
6,69
7,06
9,67
16,73
20,82
23,05
0,00 5,00 10,00 15,00 20,00 25,00
But vaccination of the president first
Nothing
Senbilise
Believer
Useful
Patriotism
Trust in the government
To test
Protect/Save/Eradicate
To set a good example
Trust in vaccines
Trust in health workers
Percentage
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Figure 2: Reasons for refusing to participate in COVID-19 vaccine research (N=337)
The proportion of the men who agreed to participate in the COVID-19 vaccination research
(38.5%) was significantly lower than that of the women (53.1%, p = 0.001) (Appendix 2).
The results of the multivariate analysis showed that participants who intended to be
vaccinated against COVID-19 (OR = 6.48, 95% CI [4.12-10.4]) and who thought that being
infected with the coronavirus would have a significant impact on their health (OR = 2.34,
95% CI [1.57, 3.51]) were more likely to agree to participate in COVID-19 vaccination
research (Table 1). The other three factors positively associated with willingness to
participate in COVID-19 vaccination research were being female (OR = 1.82, 95% CI [1.22-
2.72]), having a positive attitude towards the vaccine (OR = 1.69, 95% CI [1.09, 2.62]),
and having confidence in the Senegalese government to control the coronavirus epidemic
(OR = 1.09, 95% CI [1.02, 1.16]).
Table 1: Results of the multivariate analysis
Characteristics
Scale model
OR
95% CI
p-value
Gender
Male
1.00
- —
Woman
1.82
1.22, 2.72
0.003
1,48
1,48
1,78
1,78
3,56
5,04
15,73
29,38
34,42
0,00 5,00 10,00 15,00 20,00 25,00 30,00 35,00 40,00
Permission of relatives
Lack of time
Try authorities first
Don't want to
Try on health staff first
Fear of vaccine
Lack of knowledge about the vaccine
Not sure
Lack of trust in vaccines
Percentage
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Attitude towards the vaccine
Wrong
1.00
- —
Positive
1.69
1.09, 2.62
0.019
I intend to be vaccinated against COVID-19
No
1.00
- —
Yes
6.48
4.12, 10.4
<0.001
Do you think that being infected with the coronavirus will
have a significant impact on your health?
No
1.00
- —
Yes
2.34
1.57, 3.51
<0.001
Do you have confidence in the Senegalese government
to fight the coronavirus epidemic?
1.09
1.02, 1.16
0.011
4. Discussion
The results of this research are important in the context of the many controversies
surrounding various vaccines, including AstraZeneca's vaccine, which is at the heart of the
COVAX initiative for Africa. As Senegal began administering the Sinopharm vaccine in
early March 2021 and then its first doses of AstraZeneca, understanding people's
perceptions of vaccine research is essential. Indeed, in a context where there are calls for
the decolonisation of global health research and for more vaccine research to be
conducted in Africa [13,18], obtaining the views of those affected is an essential ethical
issue [28,29].
In the contemporary context of this study, it is not surprising that the most favourable factor
for wanting to participate in COVID-19 vaccine research is having the intention to be
vaccinated. It should be noted that we conducted this study before the vaccines arrived in
Senegal. The study also shows that other factors related to the health of individuals affect
the intention to participate in research, such as perceived health status, belief in the
consequences of vaccination on health, and positive attitude towards vaccination. Indeed,
several authors have pointed out the importance of the health status and risk perception
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