What were the reasons for COVID-19 vaccine refusal in Hong Kong?

By Tarun Sai LomteReviewed by Lily Ramsey, LLMOct 23 2023

In a recent study published in JAMA Network Open, researchers examined the willingness to accept the coronavirus disease 2019 (COVID-19) vaccine and reasons for hesitancy in Hong Kong.

Study: COVID-19 Vaccination Willingness and Reasons for Vaccine Refusal. Image Credit: Anishka Rozhkova/Shutterstock.com

Background

Hong Kong has been exemplary in its response to the COVID-19 pandemic until the highest daily mortality was recorded in the city. COVID-19 deaths per capita in Hong Kong are also far higher than in other high-income Asia-Pacific economies.

Hong Kong’s poor vaccination coverage in older populations might account for the observed COVID-19 mortality.

Specifically, over 82% of older adults ≥ 80 were non-vaccinated or had only received one vaccine dose, compared to 6.7% in England, 9% in Singapore, and 2.9% in New Zealand. A possible explanation for vaccine refusal could be the sustained periods of zero-COVID, i.e., no local cases, in Hong Kong.

Moreover, Hong Kong witnessed a major social upheaval before COVID-19, as a proposed bill on extradition triggered extensive social unrest for over 50 years.

As such, people in Hong Kong were polarized and mistrustful of authorities. Thus, this scenario presents a unique opportunity to investigate how political views and mistrust influence vaccination.

About the study

The present study explored COVID-19 vaccination willingness and refusal in Hong Kong. Around 18,045 individuals aged 15 or older and 1,488 children aged 10-14 were enrolled in 2009-11 and followed up until 2014.

Some of these were randomly followed up for over a decade. During COVID-19, participants were interviewed between February 2020 and May 2022. Cooperation and response rates were estimated according to standards.

Vaccine refusal in Hong Kong was compared with Singapore. The Singaporean sample was drawn from a 2016 study on mental health. The study’s primary outcomes were vaccination prevalence and vaccine refusal. Refusal was described as a lack of intention to receive the vaccine.

Willingness to accept the COVID-19 vaccine was defined as having received at least one dose, scheduled an appointment for vaccination, or intent to be vaccinated.

Political views were analyzed during the 2019-20 social unrest based on whether subjects were for (pro-establishment), against (non-establishment), or neutral. Trust in vaccine information sources (media platforms, the World Health Organization [WHO], health authorities, academics, and physicians) was assessed.

COVID-19 vaccine confidence was analyzed using statements on perceived efficacy, importance, and safety of vaccines.

Vaccine misconceptions about chronic diseases, older adults, and safety were also evaluated. The team calculated the weighted prevalence of COVID-19 vaccine willingness throughout the pandemic.

Poisson regression was used to investigate the associations between political views and trust in vaccine information sources, vaccine misconceptions, vaccine refusal, and vaccine confidence.

Findings

In total, over 28,000 interviews were conducted. The median cooperation and response rates were 63.4% and 75.7%, respectively. In 2020, nearly two-thirds of Hong Kong adults were willing to vaccinate when available.

Willingness increased to over 73%, coinciding with positive vaccine trial results. Nevertheless, willingness dropped to 55% after the Hong Kong government announced that people could not choose which vaccine to receive.

Moreover, willingness reached the lowest level (43.6%) by the start of the vaccination program and media reports of adverse vaccine effects. Individuals with non-establishment political views were more likely to refuse vaccination than those with pro-establishment views. Political participation during the 2014 Occupy Central protests was associated with COVID-19 vaccine refusal.

In Hong Kong, physicians and academics were the most trusted sources of vaccine information, followed by the WHO, government authorities, and social media.

In Singapore, academics and government authorities were the most trusted sources of vaccine information, followed by traditional media, WHO, and social media. Vaccine confidence was the highest before the rollout of COVID-19 vaccines and declined to the lowest levels at the start of vaccination programs.

There was an association between low vaccine confidence and vaccine refusal. Nearly 59% of Hong Kong adults had at least one misconception about vaccines, compared to 16.6% of Singaporean adults.

Further, over 56% of participants opposed vaccination of older adults (above 80 years). Social media, family/friends, and physicians were the top sources of misconceptions regarding priority groups.

Mistrust in health authorities, low vaccine confidence, and misconceptions mediated 72.5% of the association between political views and vaccine refusal. As such, the direct association between political views and vaccine refusal was no longer significant.

Political views, mistrust in health authorities, vaccine misconceptions, and low vaccine confidence jointly accounted for about 82% of vaccine refusal in adults aged 18-59 and 69.3% in older populations (≥ 60 years).

Conclusions

The study showed that political views may have short- and long-term associations with refusal to vaccinate against COVID-19.

This association was primarily mediated by modifiable factors, such as vaccine misconceptions, low vaccine confidence, and mistrust of health authorities.

Building trust in health authorities is vital to offset vaccine refusal. Moreover, governments should prioritize the credibility of health agencies, which would help them improve vaccination coverage.