Children younger than 5 years old–especially those younger than 2– are at high risk of developing serious flu-related complications. A flu vaccine offers the best defense against flu and its potentially serious consequences and can also reduce the spread of flu to others. Getting vaccinated has been shown to reduce flu illnesses, doctor’s visits, missed work and school days, and reduce the risk of flu-related hospitalization and death in children.
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When Should Children get a Flu Vaccine
Children should be vaccinated every flu season for the best protection against flu.
For children who will need two doses of flu vaccine, the first dose should be given as early in the season as possible. For other children, it is good practice to get them vaccinated by the end of October. However, getting vaccinated later can still be protective, as long as flu viruses are circulating. While seasonal flu outbreaks can happen as early as October, during most seasons flu activity peaks between December and February.
Since it takes about two weeks after vaccination for antibodies to develop in the body that protect against flu virus infection, it is best that people get vaccinated so they are protected before influenza begins spreading in their community.
Special vaccination instructions for children aged 6 months through 8 years of age
Some children 6 months through 8 years of age require two doses of flu vaccine for adequate protection from flu.
Children in this age group getting vaccinated for the first time, and those who have only previously gotten one dose of vaccine, should get two doses of vaccine this season—spaced at least 4 weeks apart. Your child’s health care provider can tell you if your child needs two doses.
If your child needs the two doses, begin the process early. This will ensure that your child is protected before influenza starts circulating in your community.
Be sure to get your child a second dose if he or she needs one. It usually takes about two weeks after the second dose for protection to begin.
https://www.cdc.gov/flu/highrisk/children.htm