Original Research
Immunisation & Public Health
Key Takeaways
- Low education level and lower socioeconomic status are among the strongest predictors of inadequate vaccination knowledge, but they are not the only factors — misinformation affects people across all educational backgrounds.
- The source from which people obtain health information significantly predicts their attitudes toward vaccination: those relying primarily on social media and informal networks are more likely to hold negative attitudes than those who consult healthcare professionals.
- Negative attitudes toward vaccination do not always stem from ignorance — some individuals possess factual knowledge about vaccines but interpret that knowledge through frameworks of distrust toward government or pharmaceutical institutions.
- Effective interventions must go beyond simply providing information and should address the emotional, social, and cultural dimensions of vaccine decision-making.
Vaccination: One of Medicine’s Greatest Achievements
Vaccination is one of the most successful public health interventions in history. The World Health Organization estimates that immunisation prevents between two and three million deaths every year from diseases including diphtheria, tetanus, pertussis, influenza, and measles. The eradication of smallpox and the near-elimination of polio are among humanity’s greatest collective achievements, made possible by widespread vaccination.
In Malaysia, the National Immunisation Programme provides childhood vaccines free of charge through government health facilities. Coverage rates for routine childhood immunisation have historically been high, generally exceeding 90% nationally. However, beneath these aggregate numbers lie pockets of under-vaccination driven by inadequate knowledge, negative attitudes, and logistical barriers that affect specific populations and communities.
Understanding what drives these gaps — who is most likely to have inadequate vaccination knowledge, what factors predict negative attitudes, and how these translate into vaccine refusal or delay — is essential for public health authorities seeking to maintain and improve immunisation coverage.
Knowledge Is Necessary But Not Sufficient
Research has consistently demonstrated that knowledge about vaccines is a necessary but not sufficient condition for positive vaccination behaviour. People who understand how vaccines work, what diseases they prevent, and what the evidence says about their safety are generally more likely to accept vaccination for themselves and their children. However, the relationship between knowledge and behaviour is not straightforward.
Studies in the Malaysian Journal of Public Health Medicine found that inadequate knowledge about vaccination was predicted by several sociodemographic factors. Lower educational attainment was one of the strongest predictors — individuals who had not completed secondary education were significantly more likely to have gaps in their understanding of how vaccines work, what diseases they prevent, and what the recommended vaccination schedules are.
Lower household income was also associated with knowledge gaps, likely reflecting reduced access to health education resources, less frequent contact with healthcare professionals, and the competing priorities that accompany economic disadvantage. Rural residence independently predicted lower vaccination knowledge, consistent with reduced access to health services and health education programmes that tend to be concentrated in urban areas.
However, the research also identified knowledge gaps among more educated and affluent populations, particularly regarding newer vaccines not included in the routine childhood schedule. This suggests that vaccination knowledge is not a monolithic construct — a person may be well-informed about childhood vaccines but poorly informed about adult boosters, influenza vaccination, or HPV vaccination.
What Drives Negative Attitudes?
Negative attitudes toward vaccination are distinct from, though related to, inadequate knowledge. A person can possess accurate factual knowledge about vaccines and still hold negative attitudes that lead them to refuse or delay vaccination. The research identified several key predictors of negative attitudes.
| Predictor | How It Influences Attitudes |
|---|---|
| Primary information source: social media | Exposure to unverified claims, emotional narratives, and anti-vaccine content amplified by algorithmic recommendation systems |
| Distrust of institutions | Scepticism toward government health agencies and pharmaceutical companies, sometimes rooted in legitimate historical grievances |
| Belief in alternative medicine | Preference for “natural” approaches to health; perception that vaccines are “unnatural” and therefore harmful |
| Personal experience with adverse events | Having personally experienced or knowing someone who experienced a reaction to a vaccine, even if mild, can create lasting negative impressions |
| Religious or cultural beliefs | Concerns about vaccine ingredients (e.g., porcine-derived components), fatalistic beliefs about health and illness |
| Peer and family influence | Being embedded in social networks where vaccine scepticism is normalised and vaccine acceptance is questioned |
The Social Media Factor
The role of social media as a predictor of negative vaccination attitudes deserves particular attention. In Malaysia, where internet penetration exceeds 95% and social media usage is among the highest in Southeast Asia, platforms like Facebook, WhatsApp, TikTok, and Telegram serve as primary information sources for many people. These platforms are highly effective at spreading emotional, narrative-driven content — exactly the type of content that characterises anti-vaccine messaging.
Anti-vaccine content on social media is disproportionately engaging because it relies on personal stories (a parent describing their child’s adverse reaction), fear-based messaging (claims about hidden dangers), and conspiratorial frameworks (allegations of cover-ups by governments or pharmaceutical companies). These approaches are psychologically compelling in ways that factual, statistical public health messaging often is not.
The Gap Between Knowledge and Behaviour
One of the most important insights from the research is that knowledge and attitudes do not always align, and neither perfectly predicts behaviour. Some individuals with adequate knowledge and positive attitudes still fail to vaccinate due to practical barriers — clinic hours that conflict with work schedules, distance from health facilities, cost of non-routine vaccines, or simply forgetting. Conversely, some individuals with limited knowledge and somewhat negative attitudes still vaccinate because it is socially expected or because a trusted healthcare provider recommends it.
This gap between knowledge, attitudes, and behaviour has important implications for intervention design. Programmes that focus exclusively on providing information (the “knowledge deficit” model) will miss the attitudinal, social, and practical dimensions of vaccination decision-making.
What Works to Improve Vaccination Acceptance
Evidence from international research and from Malaysian experience suggests several approaches that can effectively address both knowledge gaps and negative attitudes. Healthcare provider recommendation remains the single most influential factor in vaccination decisions — when a trusted doctor or nurse recommends a vaccine and explains why, most patients accept. Training healthcare providers in motivational interviewing techniques and vaccine communication can strengthen this already powerful channel.
Community-based interventions that work through trusted local figures — religious leaders, community health volunteers, teachers, and local politicians — can reach populations that are sceptical of formal health institutions. In Malaysia, engaging with religious authorities to address concerns about vaccine ingredients and to issue formal endorsements of vaccination has proven effective in specific communities.
Addressing practical barriers — extending clinic hours, providing mobile vaccination services, sending SMS reminders, and reducing out-of-pocket costs for non-routine vaccines — can convert positive attitudes into actual vaccination behaviour.
Implications for Malaysian Public Health
Malaysia’s vaccination communication strategy should move beyond one-way information provision toward interactive, dialogue-based approaches that acknowledge and address people’s concerns rather than dismissing them. Social media monitoring and proactive digital health communication should be prioritised, given the significant role of online platforms in shaping vaccination attitudes. Training for healthcare providers should include vaccine communication skills, with particular attention to respectfully addressing hesitancy without alienating patients. Research should continue to identify specific populations and communities with lower vaccination coverage so that targeted interventions can be developed and evaluated.