BackgroundVaccine diplomacy is a subset of global health diplomacy and refers to the use anddelivery of vaccines to achieve a country's global health goals and foreign policyobjectives. Countries have used vaccine diplomacy to increase their soft power duringthe COVID-19 pandemic. China, an emerging world power, was no exception in thistrend. By December 2022, China has dispatched 1,65 billion vaccines worldwide;approximately one-third of the Chinese vaccines have been sent to the Association ofSoutheast Asian Nations (ASEAN) countries. China attempted to increase its softpower via vaccine diplomacy to appeal to its neighbours with which it has longstanding territorial disputes in the South China Sea (SCS). Using the soft powerperspective, our study examines the effectiveness of Chinese COVID-19 vaccinediplomacy in the Philippines and Vietnam, two primary claimants in the SCS.MethodsThrough a qualitative multiple case study research design, we determine theeffectiveness of Chinese vaccine diplomacy in the Philippines and Vietnam by usingfour indicators of soft power: public opinion, foreign policy, attractiveness, and businessand trade. Data collection consisted of a semi-systematic literature search of academicliterature and newspaper articles that were published before 13 June 2022. A thematicanalysis was conducted to analyse the data.ResultsAnalysing the effectiveness of Chinese vaccine diplomacy based on the four indicatorsof soft power, our results show that only the indicators of attractiveness in Vietnam andbusiness and trade in the Philippines have somewhat improved. In contrast, theindicators of public opinion and foreign policy showed neutral or negative results forChina.ConclusionsThis study concludes that Chinese vaccine diplomacy in the Philippines and Vietnamduring the COVID-19 pandemic was unsuccessful from a soft power perspective. Onereason is that China has undermined its soft power approach by simultaneously usinghard power tactics in Southeast Asia. Using vaccine diplomacy to increase soft poweris not always desirable from a global health perspective. Instead, countries sh
