US health officials said Monday they have had no reports that arouse new safety concerns over two children's vaccines that have been suspended in Japan following the deaths of four babies.

Researchers at the (FDA) and (CDC) "have not detected new safety concerns or unusual reporting patterns" among children given the vaccines against bacteria that can cause meningitis and pneumonia, FDA spokeswoman Shelly Burgess said.

Japanese health authorities ordered doctors to stop using the two vaccines -- Prevenar, made by US-based Pfizer, and ActHIB, made by the Sanofi Pasteur wing of Paris-headquartered Sanofi-Aventis -- following the deaths of four infants who were given the shots alone or in combination with others drugs.

The infants, aged from around six months to under two years old, all died between March 2 and 4, Japanese officials said.

In addition to the four cases, Japan's health ministry said another infant died in November after receiving his second shot of the ActHIB , a Japanese health ministry official said.

The FDA and CDC are aware of the babies' deaths and of the suspension of the two vaccines in , a statement sent by Burgess to AFP said.

US health agencies were continuing to monitor the safety of all vaccines, including those against the haemophilus influenzae type b (Hib) bacteria and streptococcus pneumoniae targeted by ActHIB and Prevenar, the statement said.