The Centers for Disease Control and Prevention (CDC) state that, among children of all ages, those under 6 months of age are at the greatest risk of being hospitalized from flu.

Because flu vaccination is only approved from the age of 6 months, it is recommended that expectant mothers receive a flu shot in order to protect themselves and their newborn children from flu-related complications.

But according to study co-author Marta C. Nunes, Ph.D., of the University of the Witwatersrand in Johannesburg, South Africa, and colleagues, exactly how long maternal flu vaccination protects an infant after birth has been unclear. See more in Medical News Today