1. Introduction
The SARS-CoV-2 virus caused the COVID-19 pandemic at the end of 2019, with the initial cases identified in Wuhan, China. Its origin remains unclear, but after many epidemiological studies and several hypotheses, introduction between humans through an intermediate host is considered the most likely route [
1]. Given the rapid transmission of the virus, the World Health Organization (WHO) has activated the R&D Blueprint, whose strategy was launched in February 2020 and defined two goals: (i) immediate priorities, to accelerate research in order to contribute to containing the epidemic and facilitate optimal care for those affected; and (ii) a mid-long term, to promote global research platforms to prepare for “unforeseen epidemic and encouraging accelerate research, development and equitable access, based on public health needs, to diagnostics, therapeutics and vaccines” [
2] (p. 2)
Although some people have reported only mild or moderate symptoms, this new virus proved highly transmissible and lethal, with more than 6 million deaths and approximately 450 million positive cases worldwide [
3] in nearly 15 months. Variants Alpha, Gamma and Delta showed higher pathogenicity, whereas Beta and Omicron improved peoples’ immune defence, elevated reinfections and increased transmissibility [
4]. According to the European Centre for Disease Prevention and Control (ECDC) [
3], Omicron is dominant in transmission and has a reduced impact on severity, but its impact on transmissibility is unclear. This situation required rapid response through vaccination. Despite the WHO’s strategy to accelerate research and produce the vaccine, many people are engaged in social movements sharing information that leads to the perception of threats from COVID-19 vaccines, leading to vaccine hesitancy [
5]. Such movements have been already observed for other vaccines before COVID-19, making it difficult to attain Sustainable Development Goal (SDG) 3 and its target 3.8 (which aims at vaccines for all) [
6], and were largely disseminated in digital media. They have been defined as a set of attitudes ranging from reluctance to refusal of the vaccination, despite the availability of vaccination services [
7]. There are several determinants for vaccination hesitancy, including contextual influences and individual and group influences, as well as vaccine and vaccination-specific issues, including the recent novelty of the COVID-19 vaccines and insufficient testing and knowledge [
8].
Given the short period to create and release COVID-19 vaccines and some mistrust about vaccines’ safety and effectiveness, great discussion and decision-making processes have occurred, accompanied by intense social controversy [
9]. Therefore, when this controversy arises in the classroom, one faces socially acute questions (SAQ), where teaching practice needs to combine school knowledge with social realities [
10]. On the other hand, contemporary science education aims to prepare citizens to reason about environmental socio-scientific issues impacting their future to promote active participation and the decision-making process, which is a target of SDG 4, quality education and lifelong learning opportunities, promoting knowledge and skills acquisition [
6]. Thus, an educational response that prepares students to be active in decision-making processes is the teaching of SAQs [
11].
An SAQ has the following characteristics: (i) it is acute in society, challenging the social practices of all the interveners in school, reflecting their social representations, being considered an important issue by the society and raising the debate, as well as having media coverage, becoming the school actors familiar with the subject; (ii) it is acute in background knowledge, since it promotes debate and controversy among the specialists from disciplinary and professional fields, diverse paradigms from human, social and even exact sciences are in competition, and references based on social, cultural and political practices can result in the background for knowledge to be taught in school; (iii) it is an acute question in knowledge taught, becoming all the more “potentially acute” in what is learned in school because it is acute on the other two levels of knowledge (social and background) [
10] (p. 25).
SAQ can be linked to socio-scientific issues (SSI). In science education, the latter was introduced as a way of addressing social dilemmas that interact with the scientific domain and have implications in several fields, such as biology, sociology, ethics, politics, economics and the environment [
10]. Of this relation between SAQs and SSIs, some authors [
12] claim that SSIs are socially controversial or life issues that involve not only scientific topics but also economic, political and ethical aspects and moral dilemmas. These authors further reference that one continuously faces SSIs, namely genetically modified organisms, nanotechnologies and climate changes. In this sense, vaccination for COVID-19 can also be considered both an SAQ and an SSI.
The key elements for the pedagogical practice of SSIs are the following:
(1) Constitute practical applications of scientific knowledge to real-life problems, (2) take place in the intersection of science and society, therefore supporting the idea that science must progress consistently and in accordance with the values and needs of the society in which it is developed and (3) are present in public discussion, often through the media [
13] (p. 2).
SSI lessons are a way to promote students’ development of scientific literacy and an opportunity to debate and reconstruct the meaning of scientific competence. SSIs in society require a dedicated competence called socio-scientific reasoning (SSR), which includes the skills of complexity, examination, ongoing inquiry and scepticism. Ongoing inquiry focuses on the nature of an SSI as a problem not yet clarified but under permanent research and development, whereas scepticism refers to students’ skills to critically analyse the information obtained about an SSI considering the possible bias on the part of the information sources [
13]. These two competencies seem very important in the COVID-19 context, with a new vaccine to be produced and the upsetting news about their side effects. In addition to the fact that this pedagogical strategy is explored every year in HBH lessons, in 2020 and within the context of universal vaccination for COVID-19, this strategy was even more relevant.
We consider that SAQs and SSIs are relevant matters to be discussed in the “Human Biology and Health” (HBH) curricular unit of a teacher training course. Therefore, we introduced the vaccination topic in the immune system theme of the HBH unit. This topic was of utmost interest when scientists were trying to deliver a vaccine quickly to control the dissemination of SARS-CoV-2 and to contain the loss of so many human lives. Indeed, we intended to assess how the immune system and vaccination teaching topics contributed to students’ scientific knowledge mobilisation for understanding, acceptance and the decision-making process about vaccination.
Therefore, our research question is: how can learning about the immune system and vaccination principles influence the students’ conceptions of COVID-19 vaccines? To answer this question, the conceptions of students who had learned these topics in the HBH unit were compared to the conceptions of those who had not yet studied it. Secondly, the influences of some individual factors were also analysed. In this sense, the two null hypotheses were formulated: H0.1 = there are no significant differences in conceptions of COVID-19 vaccines between the students who had or did not have HBH lessons about the immune system; H0.2 = students’ secondary school background and other individual factors do not lead to significant differences in their conceptions about COVID-19 vaccines.
4. Discussion
The present study showed that students who already studied the university HBH curricular unit had more scientifically acceptable conceptions about the COVID-19 vaccines, indicating that they transposed their learning to the problem and controversy they faced about vaccination. Therefore, this study answered the research question: how can learning about the immune system and vaccination principles influence the students’ conceptions of COVID-19 vaccines? And the first null hypothesis, H0.1, is rejected, as significant differences were found.
The sample was almost all female (101 women in 102 students), which generally feels healthy and not at risk for COVID-19, which is expected for young people near their twenties. Few of them (13.7%) had had contact with SARS-CoV-2 at the moment of data collection. Therefore, these sample characteristics can explain the positive point of view and confidence in the vaccine emergence.
Students from the secondary school area of sciences and technologies revealed more acceptable conceptions about the COVID-19 vaccine, indicating the significance of the previous study area. On the other hand, these students were less confident in vaccine benefits at the beginning of the vaccination process compared to students from the socioeconomic sciences or languages and humanities areas, who were more favourable to the rapid effect of the vaccine. This result leads to the rejection of the second null hypothesis, H0.2, since there are significant differences associated with students’ secondary school background.
Data from the six open-ended and the closed-ended questions gave interesting, interlinked results, as interpreted below. For the first question of having vaccines for COVID-19 already available, students were divided, with nearly half having a positive view and another half expressing a negative opinion, based on the time to produce the vaccine and the fear of side effects, which are determinants of vaccination hesitance listed by the ECDC [
8]. Similar results were found with a university student sample from the USA [
19], with 47,5% of students hesitating about the COVID-19 vaccine’s effects. Interestingly, in the present study, students who studied languages and humanities in secondary school had a more favourable opinion about taking the vaccine. A possible interpretation for science and technology students being more afraid of vaccine side effects is that they know more about mechanisms of action, microscopic and sub-microscopic dimensions (cellular and molecular) and clinical trial processes. In contrast, socioeconomics or languages and humanities students may be less aware of these technical, scientific details and more concerned about epidemiologic politics and pandemic control for the general population’s well-being and thus are more confident in vaccine safety.
Those who are more interested and search more for information on science, medicine and health, namely in digital media, tend to be more doubtful about COVID-19 vaccine safety, being that the information quality is a problem rather than its availability [
7]. Even healthcare workers accept but have some fear and little confidence in the immunisation scenario, as observed in a multicentric study in France [
20]. Similar results were found in the USA before the vaccination began [
21], with only 36% of the healthcare workers being willing to be vaccinated as soon as possible.
Compared to the first- and third-year students, the second-year students gave a higher proportion of scientifically correct answers about the vaccine contents. This could be due to the teaching–learning process about vaccination in the HBH curricular unit they had had two months before the data collection and the process of vaccination being, at that time, a very controversial issue. Therefore, it demonstrates the positive influence of the vaccination topic of the HBH curricular unit on students’ scientific conceptions and learning. Most students expressing the scientifically incorrect conception that a vaccine is composed of antibodies were from the first year. It is understandable since they had not yet had the HBH curricular unit, reinforcing the positive influence of the teaching–learning process on antibody and antigen concepts. A few students in the second and third years also said vaccines contain antibodies, indicating that they did not acquire the correct scientific conceptions or weakened with time. Scientific conceptions acquisition can interact with intuition, and previous conceptions can be obstacles to conceptual change as well, which involves shifts in the meanings of concepts, accommodation of the new concepts in the explanations and management of the relations between concepts [
22].
About half of the students (61) who said they were at risk for COVID-19 believed that vaccine composition is the virus or its genetic material, which explains their fear of being infected by the vaccine. Indeed, 33 feared an allergic reaction to the vaccine and 28 mild symptoms of COVID-19, as the data triangulation between the categorical variables and the closed-ended questions revealed. These misconceptions about vaccines and consequent fears can be seen as vaccination hesitancy determinants, them being of individual or group influences [
8]. A recent meta-analysis of 56 studies [
23] identified many of the highest risk factors for COVID-19 vaccine hesitancy, such as being a woman under the age of 50, having lower educational attainment, being a non-healthcare-related worker and having no children at home.
For the third question of who should be vaccinated first, students elected health professionals, followed by the elderly and people at risk. The COVID-19 pandemic has presented a dilemma worldwide: with the number of cases exploding and a limited stock of vaccine doses, who should be immunised first? Therefore, each country organised a sequential list of priority groups for national COVID-19 vaccination operationalisation. In general, the criteria were based on WHO principles [
24], where the table of priorities starts with the principle of human well-being, the goal of reducing deaths and the burden of disease, electing as priority population groups those at high risk of disease or death (including the elderly and patients with comorbidities) and those at high risk of being infected (where health workers are included). Most countries have opted to start vaccinating frontline health workers [
21], in addition to the elderly, as in the UK [
25] and Portugal [
26], as a group considered to be most at risk. Indeed, the concerns of this study’s students align with these worldwide criteria by indicating health professionals, the elderly and patients [
24,
26] as a priority, considering these three groups as high risk.
The fourth question about vaccines from several brands showed the economic or competition reason as the more frequent category. Most of these answers were from first-year students who had not yet had the HBH curricular unit. Curiously, more students from sciences and technologies and languages and humanities showed this conception, compared to less than half from socioeconomics. Some students seemed hesitant about this issue, showing opposing but well-justified ideas. It can be interpreted as a dilemma and reasonable argumentation, which shows this issue’s SAQ and SSI nature. Students’ argumentation was based on scientific efforts and economic and business interests.
When students are engaging in SAQs, they engage with socio-scientific reasoning (SSR), which involves reasoning including other fields beyond science, “including values, economics, local and global perspectives governance issues and a variety of stakeholder perspectives” [
11] (p. 826). The introduction of SAQs in education involves the development of competencies to argue opinions and to assume positions on social issues, as well as to develop science literacy and students’ empowerment about controversial issues [
10]. Different arguments can be interpreted based on the six styles of scientific reasoning, which may vary according to specific historical contexts, although the success of science education can be attributed to cognitive tools, resources and styles of reasoning to argue for several ideas [
27]. In this sense, the teaching–learning process promoted students’ competencies to argue and take positions about this SAQ (several vaccines for COVID-19) instead of having students without opinions. Given these results, we are still more motivated to promote opportunities to implement a specific program of six styles of reasoning in biology [
28].
Regarding the fifth question on the news about allergic reactions to the vaccine, the results of this study show that vaccines are considered safe by students. However, they consider that adverse reactions can occur as with any other vaccine due to scientists’ short time to create the first vaccine against COVID-19. It was also observed that, in the opinion of some students, vaccines were developed in record time precisely because of the scientific advances of the last decades, which nowadays allow new technologies to be developed even faster. However, underlying this idea, there is still fear and mistrust on the part of some respondents. This study revealed the predominance of students’ positive attitudes towards vaccines, even in the context of growing anti-vaccination discourse.
It is recognised that the vaccine against COVID-19 was developed rapidly by implementing the R&D Blueprint strategy [
2] to decrease the number of COVID-19 cases in great expansion worldwide. Currently, the disease has claimed more than 6 million victims, and scientists worldwide have dedicated themselves fully to finding efficient solutions to the problem. The existing vaccines result from different biotechnology processes, but all have been shown to be safe and effective. Furthermore, vaccines, as with any immunobiological product, are renowned for their innumerable inherent advantages in protecting health, despite the potential risks of adverse effects, which, in the vast majority of cases, are rare, mild and controllable [
29]. Therefore, the development of vaccines against the new SARS-CoV-2 represents one of the main desires of the world population and represents an extraordinary advance in science.
The vaccination process against COVID-19 brought an air of hope while simultaneously reigniting the debate about the importance of vaccines for disease control and how these immunisers are developed in research centres and laboratories.
For the sixth and last open-ended question, students considered the health high risk as the main argumentation for initiating vaccination in an older woman in the UK. In third place was the category related to the care and attention to the elderly. In this sense and adding also the small percentage of those who justify the decision as an example to motivate young people, we observe that the majority (more than 60%) of students believe in a positive intention of the policy makers. However, an important percentage of students were not confident in this option, since more than 20% understood the decision based on the depreciation of the lives of the elderly and their use to test the vaccine, considering an attempt to test it with less grief in case of death. As is well known, with advancing age immunity decreases; consequently, elderly people are more susceptible to infectious diseases, and vaccination is the best way to benefit older people [
30]. For the 37 older people in the UK (ages 70–89) who followed up after the second immunisation, it was verified that the protection reduced in 3 to 20 weeks, so a third boost was required to keep their immunity to SARS-CoV-2, which also provided benefits against several variants [
31]. In addition to the greater immunological weakness, the higher prevalence of chronic diseases substantially raises the risk of dying for the elderly compared to other age groups [
32]. To reduce mortality and the need to give visibility to the particularities of elderly care, vaccination against COVID-19 has been made feasible and prioritised for this age group in several countries, following WHO orientations [
24], vaccination being understood worldwide as the fundamental strategy to promote and protect the health of the elderly. In our students’ conceptions, elderly people were included in the priority groups, and the choice to vaccinate a 90-year-old woman first was positively understood with the primary objective of protecting life and avoiding deaths, which is the most important outcome of any disease.
Other students’ opinions referred to the example and incentive for younger people to adhere to vaccination and also related to economic and advertising aspects. Beyond a health issue, the vaccine becomes a subject permeated by the geopolitical and economic interests of different nations, industries and interest groups. Wider retrospective research collecting data between 2015 and 2019 from 149 countries [
33] indicates an increase in vaccine confidence. However, European and Asian countries revealed less confidence, partly due to the anti-vaccine movements in France and Poland [
33]. This study reports more opinions about children’s immunisation, but the authors conclude that the COVID-19 pandemic emergence can be a valuable situation to see where more work is needed for better confidence in vaccines for saving lives. The protection of the elderly must be guaranteed by humanised and quality healthcare, as well as by positive influences. Interestingly, our students, pre-service teachers, have shown themselves to be sensitive to the needs of this most vulnerable group.
At the moment of vaccination emergence in Portugal, the students feared allergic reactions and intended to be vaccinated, though not immediately. Fear of adverse effects associated with vaccine hesitancy among university students was also found in a study with a bigger sample (n = 840) in Mexico City, also during early vaccination implementation [
34].
The second-year students were those more interested in being vaccinated, but simultaneously, they did not want to be vaccinated immediately (in the beginning of the vaccination process). This can be interpreted based on the recently acquired knowledge about the vaccine action mechanisms at the HBH curricular unit, in addition to alarming media information and strong social controversy related to the short time to obtain the vaccine [
9]. Nevertheless, several factors can influence vaccine acceptance and hesitancy, including academic background, socioeconomic context, beliefs and others [
34]. In contrast to the second-year students, those of the first year thought that it would be enough to be vaccinated only once. So, this is evidence of the positive effect of the HBH lessons about immune defence during the second year. Thus, these students who had already learnt the vaccination principles revealed knowledge about the primary and secondary immune response [
15], understanding the need for contact with the antigen more than once to develop protection.
Furthermore, the students coming from the secondary school science and technology area were more favourable to vaccination, which is understandable due to their previously acquired scientific knowledge. However, they were frightened of the vaccine side effects and did not want to be vaccinated immediately. Therefore, it can be interpreted as a scientific reason and argumentative competency, based on more detailed and deepened knowledge balancing the benefits and risks of the vaccine, bringing their scientific reasoning for their life and decisions. Indeed, it is the case to think that this issue of COVID-19 vaccination addresses the nature of SSIs as a problem that is not very clearly defined and is under constant investigation and development. The “skepticism is related to the students’ ability to critically analyse the facts or information that are provided about an SSI considering the possible bias towards the sources of the information” [
13] (p. 5).
This interpretation is reinforced by the results of students coming from the secondary school socioeconomic sciences area, who were most willing to pay for the vaccine and trusted less that the vaccine could develop COVID-19, which means they were not mobilising scientific knowledge for their decisions.
Not many studies were found in searching for specific literature on students’ conceptions of COVID-19 vaccination. Only some studies about other general university students’ conceptions, more specifically biological sciences students, about the immune system and vaccination were found in Brazil [
35,
36,
37] and Spain [
38]. However, no studies were found on Basic Education university students who are in the process of their initial training to be preschool, primary and/or elementary school teachers, concerning conceptions about the COVID-19 vaccine. Therefore, this study is innovative and contributes to understanding the argumentation of a part of the population: Basic Education (BE) university students.
In this way, our research contributes to some sustainable development goals [
6], namely: goal 3, “ensure healthy lives and promote well-being for all at all ages”, focusing more on 3.8, discussing essentially the access to safe and effective healthcare services and vaccines for all; goal 4, having in mind equitable quality education, more precisely for 4.4.—increasing the number of young people with relevant skills—and for 4.7 on knowledge and skills acquisition for promotion of sustainable development and lifestyles.