2-Dose Influenza in Kids: We Must Do Better

The Advisory Committee on Immunization Practices (ACIP) recommends all children aged 6 months through 8 years receive 2 influenza vaccine doses during their first vaccination season to ensure adequate immune response. Some children who have been vaccinated in previous seasons also need 2 doses, which is usually necessary when circulation of new strains (such as H1N1) is anticipated and they are added to an influenza vaccine.

Vaccinating against influenza infection in young children can prevent medical complications and hospitalization. The November 2016 issue of Vaccine published a study that looks at 2-dose adherence in children.

Researchers from the CDC analyzed data mined from more than 2.6 million children whose vaccinations were recorded at 6 immunization information system (IIS) sentinel sites. They determined how many of the children had full vaccination coverage, defined as complete 2-dose compliance in the 2010-2015 influenza vaccination seasons. They also looked at vaccine coverage in children for whom ACIP recommended 1 dose.

One-dose influenza vaccination coverage stayed steady at 60% to 67% over the years in children aged 6 to 23 months. As children aged, vaccination rates fell. Roughly 45% of children in the 2- to 4-year-old range were vaccinated, and approximately 36% of 5 to 8 year olds received 1 dose as recommended by ACIP. Coverage was slightly better in 2015 than in 2010, but rates were low overall.

Two-dose compliance was modest in children 6 to 23 months, and similar to compliance with 1-dose rates (range: 63% to 68%). It was very low in older children (<15% to 20%). Overall, only half of children who required 2 doses in the 2014-2015 season received them.

The researchers encourage providers to identify children who need 2 doses of influenza vaccine early, and begin the series as soon as possible. This ensures that children receive 2 doses before influenza peaks.