Influenza is an acute respiratory illness caused by influenza A or B viruses. It occurs in epidemics nearly every year, mainly during the winter season in temperate climates. Influenza viruses change their antigenic characteristics frequently, and their subsequent spread depends upon the susceptibility of the population to viruses with novel antigens. Annual influenza vaccination is an important public health measure for preventing influenza infection.
The protection provided by influenza vaccines is based on induction of virus-neutralizing antibodies, mainly against the viral hemagglutinin. Influenza is typically characterized by fever, cough, sore throat, runny nose, headache, muscle and joint pain and malaise. In young children, impaired respiration, dehydration, altered mental status, and irritability signify serious disease. The American College of Obstetricians and Gynecologists’…
