Vaccine events raising public concern and associated immunization program policy and practice changes, China,...

Several vaccine events causing public concern have occurred in China that were investigated and responded to by the central government. We describe causes, influences, and policy or practice changes associated with vaccine events that occurred between 2005 and 2021. We make recommendations to foster resilience in China's Expanded Program of Immunization (EPI) system and vaccination enterprises and to sustain vaccine and program confidence.

Our study included all vaccine events since 2005 that were investigated and responded to by the central government of China. We verified mainstream and social media visibility of the events through Internet search. We extracted event times, causes, investigation processes, results, actions, and policy or practice regulation changes from official reports of government meetings and from official websites with media briefings.

Seven vaccine events were identified, each of which caused more than 100,000 mainstream or social media reports nationally or nationally and internationally. The events ranged in magnitude from 145 children receiving out-of-date oral poliovirus vaccine to a measles supplementary immunization activity involving 103 million children. Few, if any, children were directly harmed by vaccines in the events. Government responded to each event with program or policy changes, and in one case, with legislation. Responses affected the conduct of campaigns and supplementary immunization activities, use of schools as vaccination venues, financial incentives for vaccinating with non-program vaccines, vaccine procurement and distribution, and program policy making. The most fundamental response was enacting the country's first vaccine law, the 2019 Vaccine Administration Law, which guides virtually all aspects of vaccination work, from vaccine development through regulation, program implementation, and safety and impact monitoring.

All seven events generated substantial national and international mainstream and social media criticism and discussion, most commonly expressed through concerns of vaccine safety or vaccine effectiveness. Most had temporally associated temporary declines in vaccine confidence and coverage, jeopardizing decades of vaccination effort. The central government responded to each event by attempting to address root causes. Faithful implementation of the Vaccine Administration Law is fundamental to program strengthening and sustaining confidence of families, stakeholders, and government in vaccines and immunization in China.