PandemicPreparedness

Babies born to mothers who receive a flu shot during pregnancy are much less likely to get flu or need hospitalisation for flu in the first 6 months of life. This is the main conclusion of a paper published in the journal Pediatrics. Researchers from the University of Utah School of Medicine report that the babies whose mothers were vaccinated when pregnant had a 70 percent reduction in laboratory-confirmed flu cases and an 80 percent reduction in flu-related hospitalizations compared with babies whose mothers weren't immunized. The study looked at the anonymised health records of more than 245,000 pregnant women who between them gave birth to over 249,000 infants over nine US flu seasons from December 2005 through March 2014. Around 10% of the women -- 23,383 -- reported being vaccinated while pregnant compared with 222,003 who said they were not vaccinated although the rate of vaccination only increased after the 2009 H1N1 pandemic. When the authors looked at the two groups for the first six months after birth, 97% of infant flu cases were in babies whose mothers had not received the flu shot during pregnancy. Of the 658 infants, 151 needed hospital treatment and all but three of these babies were born to non-immunized pregnant women.

"Babies cannot be immunized during their first six months, so they must rely on others for protection from the flu during that time, " says the study's lead author, Julie H. Shakib, D.O., M.S., M.P.H., assistant professor of pediatrics. "When pregnant women get the flu vaccine there are clear benefits for their infants." The researchers confirmed that this was not a chance observation when they looked at the rates of another viral infection which affects infants. They found that the number of cases of RSV (respiratory syncytial virus) was unaffected by flu vaccine (as expected) and there was no significant difference between the two groups.

"Pregnant women are a high-risk group during influenza season and influenza outbreaks and should receive vaccinations," according to one of the authors. Although vaccination rates among pregnant women have increased since the H1N1 pandemic, all pregnant women should be offered and are recommended to receive the flu vaccination during their pregnancy.