The effect of Chinese vaccine diplomacy during COVID-19 in the Philippines and Vietnam: a multiple case study from a soft power perspective

The study examines how effective China’s COVID-19 vaccine diplomacy was in the Philippines and Vietnam from a soft power perspective. Global health diplomacy can both address health challenges through international cooperation and be used instrumentally to pursue non-medical objectives. During COVID-19, vaccine diplomacy emerged as a key tool, with China pledging vaccines as a global public good and delivering large quantities worldwide, especially to ASEAN. Given longstanding territorial disputes in the South China Sea and China’s broader strategy to cultivate influence among neighbors, the research focuses on whether Chinese vaccine provision improved China’s soft power—measured via public opinion, foreign policy alignment, attractiveness, and business/trade—in two key claimant states, the Philippines and Vietnam. Understanding this effectiveness is important due to the risk of SCS escalation and China’s emphasis on peripheral diplomacy to secure a stable, friendly neighborhood.

Existing work on Chinese vaccine diplomacy in Southeast Asia is mixed and often implicit on soft power outcomes. Regionally, scholars note reshaped relations with varied country-level receptions, persistent concerns over Chinese expansionism, limited strategic trust gains, and in some accounts improved Chinese image. Single-country cases show context-specific dynamics: in Indonesia, vaccine diplomacy arguably improved bilateral ties; in Malaysia, reliance on Chinese assistance persisted despite downgrading Sinovac’s role. For the Philippines, prior studies suggest limited positive impact on bilateral relations; for Vietnam, vaccine diplomacy did not mitigate entrenched distrust. The literature lacks a systematic multiple case analysis of the Philippines and Vietnam specifically from a soft power perspective, which this study addresses using four targeted indicators.

Design: Qualitative multiple case study of the Philippines and Vietnam to capture in-depth, contextualized understanding without direct cross-case comparison, focusing on themes that transcend cases. Analytical framework: Soft power assessed through four indicators relevant to China’s motivations and available data—public opinion, foreign policy, attractiveness, and business/trade. Data collection: Literature search (26 May–13 June 2022) across academic databases (Google Scholar, Web of Science, PubMed, Scopus, JSTOR, ScienceDirect) and mainstream news via Nexis Uni. Search terms: “China”, “COVID-19”, “vaccine”, “diplomacy” combined with “Philippines” or “Vietnam”. Inclusion criteria: English language, accessible full text, and sufficient quality per PRISMA 2020 checklist; relevance screening applied. Final corpus: 63 items (28 academic, 35 newspaper) plus 5 supplementary sources (four ISEAS State of Southeast Asia surveys 2019–2022; one book chapter), totaling 68 sources. Data analysis: Deductive thematic analysis using the four soft power indicators as a coding framework to identify and synthesize themes and evidence within each case.

- Overall effectiveness: Chinese vaccine diplomacy yielded limited soft power gains. Only Vietnam’s attractiveness indicator and the Philippines’ business/trade showed modest improvement; public opinion and foreign policy remained neutral or negative for China in both countries. Philippines: Public opinion—China remained unpopular; in July 2020, 58% of adults expressed little trust in China (SWS). Vaccine acceptance was low: Dec 2020 YouGov showed <20% confidence in Chinese vaccines; Apr 2021 SWS, only 19% preferred China as vaccine source vs 63% for the US; 95% of Philippine General Hospital staff disapproved Sinovac. In 2022 ISEAS expert survey, 9.0% trusted Sinopharm/Sinovac vs 54.5% Pfizer/Moderna; only 1.5% saw China as benevolent; worry over China’s political/strategic influence remained high (88.5% in 2022). Foreign policy—Despite early rhetoric hinting at restraint on SCS criticism, Manila maintained resistance to Chinese activities, expanded patrols, conducted US-Philippines exercises, and restored the Visiting Forces Agreement after US vaccine donations—a win for US vaccine diplomacy. Attractiveness—Very low: in 2022 only 1.0% would choose China for study; 0.5% chose China for holidays (ISEAS surveys). Business/trade—Despite COVID-19 headwinds (e.g., banana export impacts, BRI delays), Chinese investments increased by 82.5% in the first five months of 2020; Wang Yi pledged $1.3 billion in loans and $77 million in grants (Jan 2021). Vietnam: Public opinion—Deep-rooted anti-China sentiment persisted; strong aversion to Chinese vaccines (only 4.2% of experts trusted Sinopharm/Sinovac vs 55.6% Pfizer/Moderna in 2022 ISEAS). US seen as main helper during COVID-19 (52.8% in 2022 vs 16.0% for China). Concern over China’s influence remained high in 2022 (economic 72.8%; political/strategic 80.3%). Foreign policy—No discernible shift toward China; Vietnam condemned Chinese drills near Paracel Islands (Aug 2021). The US achieved wins (monetary policy agreement; Vietnam implicitly welcomed AUKUS). Attractiveness—Improved: first-choice study in China rose to 11.1% (2022) from near-zero prior; favorite holiday destination rose to 10.4% (2022) from ~5%. Business/trade—China is a top partner, but no notable surge in projects tied to vaccine diplomacy; Vietnam showed resistance to BRI and saw no new major cooperation linked to vaccines.

Findings indicate Chinese vaccine diplomacy did not substantively enhance China’s soft power in the Philippines or Vietnam. Entrenched anti-China sentiment, concerns over vaccine efficacy, pricing controversies, delivery delays, and transparency issues limited positive shifts in public opinion. Foreign policy stances on the South China Sea did not change in China’s favor; both countries continued to oppose Chinese assertiveness, while the US realized visible diplomatic gains through vaccine donations. Vietnam showed some improved attractiveness toward China, yet levels remained modest relative to Western destinations. The Philippines saw slight gains in business/trade (investment upticks and pledged loans/grants), but these did not translate into broader soft power wins. Importantly, China’s simultaneous hard power actions in the region undermined its soft power strategy, reflecting a lack of contextual intelligence and a failure to calibrate hard and soft power (“smart power”). Despite limited soft power returns, Chinese vaccine supply still contributed to global health by filling early supply gaps and serving contexts where cold-chain requirements constrained mRNA vaccine uptake. The study underscores the tension between deploying vaccines for geopolitical influence versus equitable global health objectives, recommending emphasis on multilateral cooperation and equity to prevent reinforcing asymmetrical power relations.

This multiple case study concludes that Chinese vaccine diplomacy during COVID-19 was largely unsuccessful in enhancing China’s soft power in the Philippines and Vietnam. While Vietnam’s attractiveness toward China rose and the Philippines saw modest business/trade benefits, public opinion remained predominantly negative and foreign policy positions did not shift in China’s favor. The analysis highlights how hard power behaviors can blunt soft power efforts and how vaccine efficacy perceptions and transactional framing constrain diplomatic returns. Future research should: (1) conduct longitudinal analyses to assess long-term soft power effects; (2) compare outcomes across other regions; (3) examine US vaccine diplomacy in Southeast Asia for comparative insights; and (4) explore models of global health and vaccine diplomacy prioritizing equitable access and addressing power asymmetries.

The study establishes correlation rather than causation between vaccine diplomacy and soft power outcomes. It is limited to English-language sources, potentially missing local-language perspectives. Soft power effects may manifest over longer horizons; the study’s timing was relatively close to the main vaccine diplomacy period. Reliance on secondary literature introduces potential biases, mitigated by diverse source inclusion and quality criteria. Attractiveness was measured via stated preferences (e.g., desired study/holiday destinations) rather than realized mobility, constrained by ongoing pandemic travel restrictions.