Police in eastern China have detained 37 people implicated in a scandal involving the selling of poorly refrigerated and probably ineffective vaccines.
The scandal came to light after police last month announced the detentions of a woman and daughter thought to have sold nearly £70 million worth of the suspect products nationwide since 2011.
The scandal reinforces long-standing concerns among the public over the safety of food and medicine.
Nine pharmaceutical wholesalers believed to have sold the vaccines are being investigated.
Chinese premier Li Keqiang has issued orders for government administrations to work together to conduct a thorough investigation.
Along with prosecuting the criminals involved, government officials found guilty of negligence should be held to account, Li said, according to the official government website.
“This vaccine safety incident has created deep concern among the public and laid bare numerous regulatory loopholes,” Li said.
The Food and Drug Administration on Monday ordered a thorough check on where the vaccines were distributed and how they may have been used.
The central government administration demanded local authorities investigate the nine wholesalers believed to have sold the vaccines.
The vaccines included those for hepatitis B, rabies, mumps and Japanese encephalitis.
The China office of the World Health Organisation said it stood ready to provide support to Chinese health authorities.
It said that vaccines need to be stored and managed properly or they can become less effective and that children risked not being protected from the disease against which they were supposed to have been vaccinated.
“It is important to note, however, that improperly stored or expired vaccine seldom if ever causes a toxic reaction – therefore there is likely to be minimal safety risk in this particular situation,” the WHO said.
One of the two women detained, a 47-year-old doctor with the surname Pang, is alleged to have sold about two million doses of suspect vaccines.
Shandong’s provincial food and drug safety administration has published a list of buyers and sellers.
Past scandals have involved phony infant formula discovered to be nothing but starch and bogus vaccines containing only saline solution.