Vaccine Confidence in China after the Changsheng Vaccine Incident: A Cross-Sectional Study

Public confidence in vaccines and vaccination coverage are exhibiting declining tendencies in several countries, which has led to the outbreak of many vaccine-preventable diseases (VPDs) worldwide. Driven by a multitude of determinants such as religion, politics, economics, history, health beliefs, and genuine safety issues, among others, vaccine-related negative incidents can directly and powerfully affect vaccine confidence. The aim of this study was to investigate vaccine confidence among Chinese people after such a vaccine crisis, as well as to identify the contributing factors associated with it before they evolve into a sustained decline in immunisation coverage.

In November 2017, the titer indicators of the sample-test diphtheria, pertussis, and tetanus (DPT) vaccines produced by Changchun Changsheng Biotechnology and Wuhan Institute of Biological Products were deemed to be substandard. Although no health issues were reported among vaccinated children, the main concern was that the faulty DTP vaccines might not be effective. Social media (especially WeChat) and the press began paying a substantial amount of attention to the situation, and opinion leaders and various media outlets freely presented their opinions. In addition to widespread fear and indignation, the vaccine crisis led to a universal questioning of vaccines and threatened the achievements in immunisation in China that had been accumulated over the past decades.

In fact, as noted here, a series of vaccine scandals and scares all over the world have eroded public confidence. In 1955, about 220,000 children in the United States (US) were vaccinated against polio. Approximately 200 of these children suffered from paralytic poliomyelitis, and 10 died as a result of inadequate poliovirus inactivation. This incident led to stricter standards and controls for vaccines and prompted the establishment of a vaccine adverse reaction monitoring system in the US.

For the present study, the researchers conducted an online cross-sectional investigation from September 1-25 2018, performing descriptive analysis and logistic regression to examine the associations between socio-demographic factors, cognition and attitudes towards the Changsheng vaccine incident, and vaccine confidence. Among the 1,115 respondents included in the final analysis, approximately 70% (783) were assessed as not having vaccine confidence. More than half of the respondents (54.53%) were dissatisfied with the government's response measures to the Changsheng vaccine incident. (The satisfied group tended to be most content with the top national leaders' attention (4.33), followed by the progress of the event investigation (4.08), and responsibility of the regulatory officials (4.04).)

To elaborate on the government's response: As of February 2 2019, 48 government officials involved in the Changsheng vaccine incident had been punished, and the company was fined 9.1 billion Yuan. Eighteen company personnel who violated criminal law were arrested, including the company's chairman. The Vaccine Management Law (Draft), which was discussed and approved at a State Council executive meeting, aims to ensure the safety, efficacy, and accessibility of vaccines going forward. Indeed, the researchers suggest that the public crisis caused by this vaccine incident has accelerated the reform of China's vaccine management and has sped up its related legislature work.

The logistic regression model indicated that vaccine confidence was positively associated with the degree of satisfaction with the government's response measures (odds ratio (OR)=1.621, 95% confidence interval (CI)=1.215-2.163), attitudes towards the risks and benefits of vaccination (OR=1.501, 95% CI=1.119-2.013), concerns about vaccine safety (OR=0.480, 95% CI=0.317-0.726), and vaccine efficacy (OR=0.594, 95% CI=0.394-0.895).

In the wake of the Changsheng vaccine incident, the researchers conclude that a coordinated effort is required to restore public confidence in vaccines in China. The fact that the DTP vaccine is mandatory for children starting school in China offers a standard to be followed and can, according to the researchers, facilitate quicker restoration of the public's faith in the vaccination programme and ensure greater accountability in the future. "A truly open and transparent regulatory system should be established, and punishment for negative vaccine incidents as a part of post-event control should be taken and implemented seriously."