China has been rocked by another product safety scandal, this time involving vaccines. There are no reports of people being harmed, but it is a timely reminder of the need for intense scrutiny of supply chains that run through China and for changes in its regulatory culture. There must be greater diligence among regulators and the Chinese government must be far less tolerant toward officials who do not do their jobs.

The most recent crisis began when drugmaker Changsheng Biotechnology Co. was discovered to have forged data related to 113,000 rabies vaccines. The drug regulator in the region where Changsheng is based also disclosed that the company last November sold more than 250,000 substandard diphtheria, pertussis and tetanus (DPT) vaccines to the Shandong Center for Disease Control and Prevention, which is in charge of public health for that province. While the vaccines did not hurt any recipients, it left them exposed to the diseases.

This is not the only incident involving drug supply and suppliers. The first public case surfaced in 2006 when an estimated 1 million children in Shanxi were given vaccines that had been improperly stored or distributed, resulting in numerous deaths and serious disabilities. A decade later, it was discovered that vaccines had been sold in Shandong Province without official approval. Incredibly, the same individual perpetrated both scandals.

Those cases involved corrupt distribution systems. Now, the problem appears to be shoddy production. The recent DPT and rabies revelations were preceded by a November 2016 case in which the Wuhan Institute of Biological Products, another major producer, sold 400,520 substandard DPT vaccines. In addition, earlier this month Zhejiang Huahai Pharmaceutical announced that it was recalling valsartan, a blood pressure and heart drug that it sells in the United States and Europe, after it was found to contain NDMA, an impurity linked to cancer. The company has acknowledged the impurity and blames a change in the production process that occurred in 2012. The drug has been sold in more than 23 countries; regulatory authorities, including those in Japan, have recalled medicines that contain valsartan.

The Chinese government has responded forcefully to the crisis. It pulled Changsheng Biotechnology’s license to produce the rabies vaccine — a bold move against the country’s second-largest rabies vaccine producer — and said that it will inspect all vaccine producers. President Xi Jinping called the scandal “serious and appalling,” and promised a thorough and open investigation. Premier Li Keqiang pledged that the government “will resolutely crack down on illegal and criminal acts that endanger the safety of peoples’ lives, resolutely punish lawbreakers according to the law, and resolutely and severely criticize dereliction of duty in supervision.” That tough line would be more convincing if Li had not made a similar promise in March 2016 after the scandal in Shandong. Then, he said that China “must fix” loopholes in the oversight of vaccine production and distribution.

The problem transcends mere “loopholes.” One of the most appalling elements of this scandal is the fact that the individual who oversaw drug safety had been put in that job after losing the post as a food safety regulator: The official had failed a decade ago to prevent milk powder manufacturers from contaminating their production with melamine, a toxic chemical. That scandal resulted in four deaths and the hospitalization of over 10,000 children. Other officials that were involved found other jobs, some high-ranking, indicating that they were not punished.

The reaction by Xi and Li reflects their understanding of the stakes in this scandal. Ineffective or tainted vaccines threaten the lives of millions of children. The scale of the problem is quickly evident: On WeChat, the Chinese social media platform, the word for vaccine appeared in 321 million articles and searches, 80 times the number of times it appeared the previous week. Failure to protect China’s most precious resource is one of the most potent threats to that government.

The scandal is also a threat to China’s ambition to play a larger role in the global drug industry. A growing percentage of pharmaceutical components are being made in China; there must be faith in their safety and effectiveness if that trend is to continue. China must ensure that its regulators have the staff, the competence and the inclination to do their jobs — today, that is subject to question. At a minimum, firms and individuals that put profit ahead of public safety must know that there is a price to be paid when they are caught.

The problems that China’s drugmakers face are not unique. Many of the supply chains in China risk being contaminated or corrupted. Given Japan’s reliance on China for many of its manufacturing products, it must apply intense scrutiny to them — both for the sake of producers’ reputations and the lives of consumers.