FRIDAY, July 8 (HealthDay News) -- Maternal influenza vaccination during pregnancy is associated with a reduced risk of laboratory-confirmed influenza hospitalizations among infants aged less than 6 months, according to a study published in the June issue of the American Journal of Obstetrics & Gynecology.
Katherine A. Poehling, M.D., M.P.H., from the Wake Forest University School of Medicine in Winston-Salem, N.C., and colleagues investigated whether maternal vaccination during pregnancy reduced the risk of laboratory-confirmed influenza hospitalizations in 1,510 hospitalized infants aged less than 6 months. Infants with fever and/or respiratory symptoms in three U.S. counties were assessed to identify the presence of laboratory-confirmed influenza during the influenza season (November to April) from 2002 to 2009. Logistic regression was used to compare exposure to influenza vaccination during pregnancy, and the outcomes of positive/negative influenza testing among hospitalized infants.
The investigators found that 10 percent of hospitalized infants had laboratory-confirmed influenza, and 19 percent of the mothers received the influenza vaccine during their pregnancy. Among influenza-positive infants, 12 percent of their mothers had been vaccinated, while amongst influenza-negative infants 20 percent of the mothers were vaccinated (adjusted odds ratio, 0.52). Compared to infants of unvaccinated mothers, infants of vaccinated mothers were 45 to 48 percent less likely to be hospitalized for influenza.
"Our findings suggest that influenza vaccination of pregnant women may reduce the risk of influenza-attributable hospitalization among infants in the first five months of life, further supporting the current influenza vaccination recommendations for pregnant women," the authors write
Several authors disclosed financial ties to the pharmaceutical industry.