Health authorities of Hunan, central China, are investigating three cases of adverse reactions to hepatitis B vaccination, including two deaths.

A one-month-old boy died on Dec. 6 in Hengshan County, two days after being vaccinated. Another eight months old died in Changning City on Dec. 9, one day after vaccination for both hepatitis B and flu. A third newborn in Hanshou County showed a severe adverse reaction after being vaccinated on Nov. 25, the Hunan Provincial Center for Disease Control and Prevention said Monday.

Three investigative teams are dealing with the cases, including the sources of the vaccines, their transportation and storage, according to Gao Lidong, deputy head of the center.

The bodies of the two babies have been sent for autopsy. The vaccines are with the National Institute for the Control of Pharmaceutical and Biological Products for analysis, said Gao.

Investigations showed storage and transport of the vaccines met requirements and medical staff were qualified and did their work in line with regulations, according to Gao.

The vaccines were produced by Biokangtai, a company based in Shenzhen, Guangdong Province. Hunan has suspended the use of vaccines from batches C201207088 and C201207090.

The China Food and Drug Administration on Saturday issued a circular urging local authorities and disease control centers not to use the two batches of the vaccines.