how long are you contagious with influenza b

People with influenza B are contagious starting about one day before symptoms begin and remain contagious for about 5 to 7 days after symptoms start. Children and individuals with weakened immune systems may be contagious for a longer period. Most people are most contagious during the first three days of their illness. It is advised to stay away from others until at least 24 hours after the fever has gone without the use of fever-reducing medications to avoid spreading the virus.