Influenza infection during pregnancy: virology, pathogenesis and clinical challenges

Seasonal influenza infections are an important cause of morbidity and mortality worldwide. Pregnant and postpartum women are at increased risk of complications from influenza infection, partly due to the altered physiologic and immunologic parameters of pregnancy. While most influenza infections in pregnant women will take a mild, self-limited course, a minority of susceptible pregnant women suffer a severe life-threatening respiratory illness. The morbidity of influenza infection during pregnancy is compounded by the potential for adverse obstetric outcomes as well as the potential for detrimental fetal and neonatal effects. Suspected or confirmed influenza infection in a pregnant woman warrants treatment with antiviral medications. Influenza vaccination is the most effective way to prevent influenza infection during pregnancy and is recommended for women who are or will be pregnant during influenza season.