A flu vaccine given to a mother-to-be may also protect her baby against falling ill, a new study suggests.

Researchers from the Johns Hopkins Bloomberg School of Public Health [1] have found that the odds of developing the flu dropped by 63 per cent in babies whose mothers received the vaccine.

In addition to the drop in flu cases, the study found:

• Babies of mothers who received the flu vaccine had a 29 per cent drop in risk for developing fever or other flu-like symptoms.
• Reported cases of respiratory illness among both vaccinated mothers and their babies dropped by 36 per cent compared to inoculated mothers and babies.
  

This is the first study to demonstrate that the flu vaccine can be effective in both pregnant women and their babies, the researchers said.

"Even though there is no flu vaccine for these children, our study shows that a newborn's risk of infection can be greatly reduced by vaccinating mom during pregnancy. It's a two for one benefit," lead study author Dr. Mark Steinhoff, professor at the Bloomberg School's Department of International Health, said in a statement.

The study included data from 340 pregnant women in Bangladesh. The findings were presented at the National Vaccine Advisory Committee [2] meeting in Washington, D.C., on Wednesday.

The research is published in the New England Journal of Medicine.

Babies under six months of age have the highest hospitalization rates due to the flu among children in the United States, the researchers said. Yet the vaccine is only approved for use in those over six months.

While it is considered safe, and is recommended by doctors, for pregnant mothers, only 15 per cent of pregnant women in the United States get the vaccine, according to information accompanying the study.

The findings indicate that "pregnant women should be encouraged to be vaccinated for the flu to protect their infants and themselves," Steinhoff said.