Influenza is an infection of the upper airway caused by the influenza virus. Upon contracting the disease, a person may be at the risk of other infections, including viral or bacterial pneumonia. Serious complications of the flu include hospitalization or even death.
Some population groups, such as elderly over 65, very young children and people who have have lung/heart diseases, certain chronic health conditions, or weakened immunity are at a higher risk for serious flu complications. Healthy pregnant women in their 2nd half of their pregnancy are also at a greater risk of hospitalization. Yet, even healthy even healthy individuals can get very sick and transmit it to others.