Flu season is approaching again, and parents should know that fall is the time to have your children immunized. This is especially important for children with asthma and other high-risk medical problems.

“It is important to get a flu shot early because vaccine shortages can arise,” says Dr. Gerald Loughlin, pediatrician-in-chief at the Phyllis and David Komansky Center for Children’s Health of NewYork-Presbyterian Hospital/Weill Cornell Medical Center.

The flu vaccine is most effective when administered during the fall months, before the onset of flu season, which usually reaches its height in early December. However, it is still appropriate in December or January to have the vaccine administered.

The flu vaccine is reformulated every year. Children, especially those with asthma, should be vaccinated on an annual basis. For most adults, the flu can be a debilitating illness lasting several days. For children with asthma and other high-risk medical problems, it can lead to more serious complications, which, in many cases, require hospitalization.

Other high-risk groups who should have a flu shot include children with chronic lung or cardiovascular disease, diabetes, kidney dysfunction, sickle-cell anemia, or any form of immune suppression. It is estimated that during major flu epidemics, high-risk individuals are two to five times more likely to be hospitalized, depending on the age group. In addition, the CDC now recommends inactivated influenza vaccination for healthy children aged 6 months to 23 months as well, in order to reduce complications of influenza.

Physicians and nurses at the Komansky Center for Children’s Health of NewYork-Presbyterian/Weill Cornell strongly urge parents to have their children immunized to provide optimal protection during December and January when flu epidemics are at their peak.