A police man showing a vaccine seized at a storage place where a person surnamed Pang and her daughter run their illegal operation and allegedly sold 570 million yuan worth of vaccines against the laws and regulations. [Photo: thepaper.com]

Authorities in eastern China have arrested two people following an investigation into illegal vaccines.

It could be the biggest case of its kind in the country.

It's been reported that vaccines worth 570-million yuan, or 88 million US dollars, were sold in China illegally, starting in early 2010.

The shocking revelation was announced by Chinese news portal Pengpai, or "the paper."

It says these vaccines were not adequately refrigerated, potentially rendering them ineffective. As a result, the lives of tens and thousands of people who used the vaccines could be at risk.

Police officers in Jinan city, Shandong province have arrested a mother and daughter who were allegedly responsible for this illegal vaccine operation.

Chen Bo is with the Jinan municipal food and drug administration:

"This could be the biggest vaccine case in China. A person surname Pang who was born in Heze got our attention in the investigation. She was sentenced by the authority back in 2009 for illegal vaccine operation. And we found expired vaccines dumped in trash by one of her employees."

The mother's surname is Pang, and she is a former doctor. The daughter, Sun, is a medical school graduate. Both are now in custody on suspicion of illegally selling 25 different types of vaccine.

Thepaper.com said the 47 year old Pang once worked as a doctor at a public hospital in Heze city, Shandong province.

She had been given a three-year prison sentence, suspended for five years, in 2009, after she was convicted of illegally selling vaccines worth almost 5 million yuan.

However, Pang allegedly continued to sell vaccines illegally until she was detained by police last year.

Policeman Chen Bo says vaccine transportation and storage are strictly controlled under the law, which requires vaccines to be adequately refrigerated between 2 and 8 degrees.

"We found the storage space to be a mess. And there are no proper refrigeration facilities. The vaccines were wrapped in paper boxes with 'ice bars,' and the room clearly is not up to standard. Individuals or organizations without the license for pharmaceutical trading, or the license for vaccine trading, are forbidden to do such business."

The suspects had reportedly bought the vaccines from about 70 salesmen at vaccine companies as well as illegal vendors in 10 provinces and cities.

These vaccines include some common types used to combat chicken pox, rabies, meningitis and hepatitis A.

Wang Yuedan, deputy head of the immunology department at Peking University's medical school, says vaccines not adequately refrigerated between 2 and 8 degrees can lose their effectiveness.

She says patients who contract serious infectious diseases, such as rabies, could die if their vaccinations prove to be ineffective.

So far authorities say they cannot work out exactly how much vaccine has allegedly been sold by the mother and daughter.

But Chen Bo says their financial records show at least 570 million yuan worth of vaccines were involved.

"According to the books we found in Pang's apartment and storage, and we also found her banking transactions, it totaled about 570 million yuan."

Police have issued statements to 18 provinces and provincial-level cities, and are trying to trace all people who may have used the suspect vaccines to ensure they receive the correct medication and are also compensated.