As the COVID-19 pandemic spreads around the world, much hope and effort have been invested in finding a vaccine (1). However, developing an effective COVID-19 vaccine will be only a first step in achieving immunity and controlling the pandemic (2). Large-scale vaccination efforts will be required, and governments worldwide are currently devising vaccination strategies. One key element of any strategy is the acceptance of the vaccine by the general public. Worryingly, surveys suggest that people’s willingness to get vaccinated against COVID-19 is far from universal (3).
Vaccination is one of the safest and most cost-effective public health interventions available (4-7). Children’s routine vaccinations, including against pneumococcus, polio, and measles, are public health success stories. A large majority of people accept children’s routine immunization. Yet, there is significant variation in vaccine acceptance, owing to a variety of vaccine-related and individual factors, which may have relevance to a future COVID-19 vaccine for children (8).
Among existing vaccines, more recently developed ones, such as the human papillomavirus vaccine, have lower acceptance rates and are more prone to generate vaccine hesitancy (9). Similarly, vaccines requiring yearly administration or those of uncertain effectiveness (such as the annual influenza vaccine) have lower rates of uptake (10). In contrast, the perception of a vaccine as being part of routine vaccination, instead of part of a specific vaccination campaign, leads to greater acceptance (11).
Likelihood of COVID-19 vaccine uptake in adults
In an extensive survey conducted in 19 countries, only 71.5% of adult participants said they were likely to accept a COVID-19 vaccine, with a wide variation across countries (3). Factors associated with adults’ willingness to accept COVID-19 vaccination have been the subject of a variety of recent surveys and studies worldwide (12,13). Of note, surveys on COVID-19 vaccine acceptance are based on the availability of a “proven, safe, and effective vaccine,” which may not be guaranteed, at least initially. Social determinants of COVID-19 vaccination intention include socioeconomic status, age, ethnicity, and political ideology (13-17). In general, greater acceptance is found among women, older adults, those with higher education, and those with greater trust in government (3).
Other individual-level determinants of intention to get vaccinated include COVID-19 risk perception, knowledge about the disease, and understanding of the impact of vaccination as a preventive measure (18,19).
Determinants of child vaccination against COVID-19
Comparatively, factors associated with willingness to have one’s child vaccinated have seldom been studied in the context of a pandemic. Few studies have examined parental intention to have their child vaccinated against influenza during the COVID-19 pandemic (20,21). Recent studies by Goldman et al. based on cross-sectional surveys showed that less than 50% of parents would be willing to have their child vaccinated against COVID-19 (18).
One study conducted with a convenience sample of parents in England showed that most parents said they would likely accept a COVID-19 vaccine, both for themselves and for their children (14). In that study, visible minorities were less likely to report wanting to be vaccinated against COVID-19, as were participants of lower socioeconomic status. However, the study did not systematically examine mechanistic explanations for the differences between sociodemographic groups. In open-text responses and interviews, the primary motivation given for getting vaccinated was self-protection, while concerns regarding a rapidly developed vaccine’s safety were a predominant worry (14).
In a study of children presenting to pediatric emergency departments from March to May 2020, 65% of caregivers reported that they intended to have their child vaccinated against COVID-19 (18). Determinants of a higher likelihood of reporting intent to vaccinate were older children, children without chronic disease, recent history of influenza vaccination, and caregivers’ concerns about COVID-19 (18).
Finally, regarding parents’ acceptance of a COVID-19 vaccine for themselves, an Australian study conducted during the first wave of the pandemic showed that 16.7% of parents were unsure, and 7.6% were unwilling to accept a COVID-19 vaccine. Of those, the vast majority were concerned about vaccine efficacy and safety, while one in four believed that the vaccine was unnecessary (22).
Vaccination in children with asthma
Asthma is a common chronic respiratory disease, affecting one in ten children, making it one of the most common chronic diseases of childhood (23,24). Children with asthma tend to have a more severe respiratory virus infection presentation, especially among those with poorly controlled disease. As such, they represent an important yet understudied group with regards to vaccination.
Regarding influenza vaccination in children with asthma, studies have shown that children were more likely to be vaccinated if they were younger, if parents believed the vaccine had good efficacy, and if parents had few worries about potential side effects. Interestingly, asthma control level did not appear to be a significant factor in parents’ decision to vaccinate (25). Importantly, children were much more likely to get vaccinated if the vaccine had been recommended by a physician (26). Studies performed during the H1N1 pandemic also showed that parent-reported intent to vaccinate among children with asthma was low, with no effect of asthma control. Still, prior vaccination for influenza and beliefs and attitudes regarding the influenza A/H1N1 vaccine were significant determinants of their decision (27). In this context, physician recommendation was a decisive factor influencing intent to have a child vaccinated. To date, we are not aware of any study examining determinants of parents’ decision to have their child with asthma vaccinated against COVID-19.
Behavioral economics
To ensure that large-scale COVID-19 vaccination efforts will be successful and to guarantee vaccine uptake, it is necessary to go beyond sociodemographic characteristics and understand the determinants of people’s decisions to get vaccinated. Differences in acceptance between age groups or across socioeconomic statuses are likely due to other factors, such as risk perception, numeracy, or risk tolerance. It is essential to understand those other factors, given that, as opposed to age and sex, they are malleable and amenable to intervention. Behavioral economics examines determinants of behaviors beyond expected utility and can help us understand people’s decisions made under uncertainty. It can also help us comprehend difficult and puzzling behaviors, such as vaccine hesitancy and vaccine refusal. Beyond its descriptive capacity, the field can also shed light on important potential interventions to encourage socially desirable behaviors like vaccination (28,29). The importance of understanding behavioral aspects of COVID-19 vaccination has been recognized by the World Health Organization, which recently published a technical report on “Behavioral Considerations for Acceptance and Uptake of COVID-19 Vaccines
Objectives
The study objectives were to measure parental intent to have their asthmatic child vaccinated against COVID-19 and identify the determinants of their vaccination decision.