Most districts dip below the required 176 days. America's traditional 180-day school year is more myth than reality in Illinois, as a jumble of state laws, rules and waivers allow districts to chip away instruction time, shorten school hours and cut the number of days students come to school.
The influenza virus nasal vaccine is a live virus vaccine. Influenza virus vaccine is also available in an injectable form, which is a killed virus vaccine. Influenza virus nasal vaccine works by exposing you to a small dose of the virus, which helps your body to develop immunity to the disease.
When WHO officials choose the strains of influenza to include in the yearly flu vaccine, they choose two strains of influenza A (one variant of H1N1 and one variant of H3N2) and one or two strains of influenza B. Most flu vaccines contain three strains of influenza but the quadrivalent vaccine and the nasal spray vaccine, Flu Mist, contain four (two strains of influenza B instead of one).