COVID-19 vaccine communication and advocacy strategy: a social marketing campaign for increasing COVID-19 vaccine uptake in South Korea

The paper addresses how government communication using social marketing can increase COVID-19 vaccine uptake amid widespread hesitancy. Following multiple waves of COVID-19, vaccination was recognized as essential, yet hesitancy driven by concerns about safety, side effects, misinformation, and poor communication impeded uptake. The study focuses on South Korea, where initial public sentiment favored a wait-and-see approach. It examines Korea’s national campaign that used social marketing to frame vaccine benefits, reduce perceived costs, and tailor messages, culminating in high coverage by August 2022. The purpose is to identify principles and strategies—particularly five key communication attributes (proactiveness, credibility, combating misinformation, social norms/prosocial behavior, coherence)—that contributed to increased acceptance, offering insights for broader application.

The theoretical framework is social marketing, recommended by WHO for vaccine confidence and uptake. Social marketing adapts commercial marketing concepts to influence behaviors for social good, grounded in customer orientation and value exchange. The marketing mix (4Ps: product, price, place, promotion) is applied to vaccination: communicating vaccine benefits (product), reducing perceived and actual costs (price), ensuring accessible service points and information channels (place), and persuasive, trusted messaging across media (promotion). Behavioral intervention tools (Hug, Nudge, Smack, Shove) complement persuasive communication to incentivize desired behaviors and disincentivize competing ones. In Korea, these were operationalized via incentives (e.g., vaccine holidays, access benefits), reminders, and constraints on non-compliance (e.g., testing requirements, temporary vaccine certificates for access).

Document analysis of communications and media from January 2021 to August 2022. Searches were conducted in Web of Science, PubMed, ScienceDirect, and Factiva using keywords related to COVID-19 vaccination recommendations and public health communication/campaigns. Government sources included the Korean Presidential Office Broadcast (KTV), Korea Disease Control and Prevention Agency (KDCA), and Korean Ministry of Health and Welfare (KMHW), covering website and non-website communications (official documents, daily briefings, announcements, news reports). Local media coverage was reviewed via the Bigkind database using keyword searches. No primary human data collection was undertaken.

- Social marketing-based communication was associated with high voluntary vaccine uptake in Korea by August 2022: 94.8% (12+ years) completed second dose; 71.3% received third (booster); 16.2% (50+ years) received fourth dose. - Pre-campaign hesitancy was substantial: 67.7% of respondents expressed concerns about safety/side effects and preferred to wait and see. - Application of the 4Ps: • Product: Communicated individual and societal benefits (protection against severe disease/death; contribution to herd immunity; return to normalcy) with evidence from trials and surveillance. • Price: Addressed safety concerns with transparent data, literacy campaigns, adverse event support/compensation; introduced disincentives for non-adoption (e.g., quarantine/testing requirements; time-limited vaccine certificate policy) while later removing unpopular measures. • Place: Ensured access via clear booking systems (web, telephone, in-person), mobile apps (Naver, Kakao) for real-time availability, diverse convenient vaccination sites, and support for older adults and remote areas. • Promotion: Free vaccines for all; broad, multi-channel outreach using trusted spokespeople (health professionals, community/religious leaders, local celebrities); reminders via texts and materials. - Behavioral interventions: Incentives (e.g., vaccine holidays, access benefits) and reminders (nudges) supported uptake; temporary access restrictions increased the cost of non-adoption. - Public perceptions improved: surveys indicated increased belief in vaccine importance (75.5%) and efficacy (74.3%); trust in KDCA was high (78% in early June 2021). Social media attention to negative keywords (e.g., side effects) diminished after campaign onset. - Five effective message attributes identified: proactiveness, credibility, fighting misinformation (fact-checking, AI monitoring; removal of >43,000 tweets and 1,000,000 misleading items), emphasizing social norms/prosocial behavior, and coherence across agencies. - By October 2021, herd immunity threshold was surpassed with 41.31 million adults (79.7% of total population) fully vaccinated.

The findings suggest that a structured social marketing approach, integrating the 4Ps and behavioral interventions, effectively addressed key barriers to vaccination in Korea—most notably safety concerns, misinformation, and access. Proactive, credible, and coherent communications preempted misinformation and maintained public trust, while messages highlighting social norms and collective responsibility resonated in a collectivistic context, reinforcing intentions and behaviors. The strategy’s combination of benefits framing, reduced costs, accessible venues, trusted messengers, and tailored incentives/disincentives translated improved attitudes into action. This demonstrates the practical value of social marketing for public health campaigns and offers a scalable model for other settings, with adaptations to local culture and media ecosystems.

Government-led social marketing communication can shape vaccine intentions and behaviors by aligning messages with public values, clarifying benefits and risks, combating misinformation, and ensuring easy access. Korea’s campaign—centered on proactiveness, credibility, misinformation control, social norms/prosocial appeals, and coherence—contributed to high vaccine uptake. The study contributes a structured set of communication attributes and an application of the 4Ps plus behavioral tools that can inform national immunization strategies elsewhere. Future research should employ quantitative designs (e.g., cross-sectional surveys, regression) to assess causal effects, and conduct cross-cultural studies to test generalizability and refine locally appropriate messaging and intervention mixes for booster and future immunizations.

The study uses a document analysis design without primary quantitative data, limiting causal inference. Findings are specific to South Korea’s sociocultural context and may not generalize to other settings. Future work should apply quantitative methods and examine diverse populations and contexts to validate and extend these insights.