Knowing someone with COVID-19 a key predictor of vaccine uptake among HK adolescents

An online survey of over 2,500 Hong Kong adolescents has identified knowing someone diagnosed with coronavirus disease 2019 (COVID-19), having at least one vaccinated parent, and receiving the influenza vaccine in the past year as three top predictors of COVID-19 vaccine acceptance.

“Vaccine hesitancy remains a significant barrier to achieving herd immunity and is considered one of the leading threats to public health. It is influenced by factors classified into three main categories: confidence [lack of trust in the safety and efficacy of a vaccine], complacency [perception of low disease risk] and convenience [vaccine access, including availability and affordability],” wrote the researchers from University of Hong Kong and Princess Margaret Hospital. [Vaccines 2021;9:160; China J Affect Disorders 2021;292:552-558; J Pediatric Health Care 2021;35:509-517; Vaccine 2015;33:4161-4164]

The online questionnaire was completed by 2,609 respondents (age range, 12–18 years) before 31 June 2021. The questionnaire contained a series of predominantly yes/no or multiple-choice questions and primarily focused on the adolescents’ intent to vaccinate and the reasons for their choice, and excluded parents’ opinions. “We aimed to explore Hong Kong adolescents’ attitudes towards COVID-19 vaccination to identify factors that could improve vaccine uptake,” explained the researchers. [Vaccine 2022;40:967-969]

Less than half of respondents (39 percent) stated that they planned to receive COVID-19 vaccine. “Significant confounding factors affecting the decision to or not to get vaccinated can broadly be split into two groups related to the vaccine hesitancy model, with either confidence in the vaccine or life experience predominantly affecting complacency and perception of disease risk,” wrote the researchers.

Top three reasons for not intending to be vaccinated were concerns regarding vaccine safety (79 percent of respondents), vaccine efficacy (52 percent), and belief that facemasks and social distancing are sufficient (26 percent).

The top three reasons for intending to receive the vaccine were concerns about becoming infected (59 percent), desire to protect own family (53 percent), and wish to return to pre–COVID-19 normality.

After logistic regression, independent significant factors associated with the intention to get vaccinated included the following: having at least one vaccinated parent, knowing someone diagnosed with COVID-19, and receiving the influenza vaccine in the last year.

“Our study showed that adolescents intending to be vaccinated [against COVID-19] are more likely to have parents who have already been vaccinated, and a large proportion of them have previously been vaccinated against influenza. This suggests that both the adolescents and their family are comfortable with vaccinations in general. We predict that their trust in vaccination is higher and they would be more likely to get vaccinated against other infectious diseases if necessary. The opposite is true of those who do not intend to be vaccinated, as they suggest safety and efficacy as their main concerns,” commented the researchers. [JAMA Network Open 2020;doi:10.1001/jamanetworkopen.2020.25594]

“Surveys conducted across the world and in Hong Kong, in particular, have revealed that more than 40 percent of respondents would prefer to be vaccinated in the final 10 percent [ie, after 90 percent of eligible population had been vaccinated],” wrote the researchers. [Vaccines 2021;9:160; https://www.hku.hk/press/news_detail_22394.html] “Our study proves that even in adolescents, vaccine intentions are highly related to confidence in vaccine and perception of disease risk. Future interventions should target these specific concerns to ensure adolescents are well educated to overcome vaccine hesitancy.”