From Medscape
News Author: Laurie Barclay, MD
CME Author: Penny Murata, MD

October 14, 2008 — The American Academy of Pediatrics (AAP) has issued updated guidelines for routine use of influenza vaccine in children and adolescents in the 2008 to 2009 influenza season, according to a statement reported in the October 1 Early Release issue of Pediatrics. This update revises guidelines originally published in a comprehensive format in Pediatrics in April 2008.

The AAP recommends annual influenza immunization for all children aged 6 months through 18 years, including those who are healthy and those who have high-risk conditions; for household contacts and out-of-home care providers of children with high-risk conditions or of healthy children younger than 5 years; for any woman who will be pregnant during influenza season; and for healthcare professionals.

Since the April 2008 guidelines, the recommended age range of children for annual influenza immunization has been expanded in these updated guidelines to include all children aged 6 months through 18 years.

“This expansion targets all school-aged children, the population that bears the greatest disease burden and is at significantly higher risk of needing influenza-related medical care compared with healthy adults,” write AAP chairperson Joseph A. Bocchini, Jr, MD, and colleagues. “In addition, reducing influenza transmission among school-aged children will, in turn, reduce transmission of influenza to household contacts and community members.”

This expanded indication now means that the following groups should be vaccinated:

All children who are at greater risk for influenza complications, such as those who are immunosuppressed or who have chronic medical conditions.</li

All healthy children aged 6 through 59 months.</li

If feasible, all children aged 5 through 18 years should be vaccinated in the 2008 to 2009 influenza season. If not, these children should be routinely vaccinated no later than the 2009 to 2010 season.

Household members and out-of-home care providers of all children at high risk and adolescents and all healthy children younger than 5 years should also receive influenza vaccine annually to lower the risk for exposure to influenza for these young children, who are at serious risk for influenza infection, hospitalization, and sequelae. In healthy children younger than 24 months, the risk for influenza-associated hospitalization is at least as great as the risk in previously recognized high-risk groups. Furthermore, children aged 24 through 59 months have greater morbidity and higher rates of outpatient visits and antibiotic use related to influenza illness.

Influenza vaccine has not been approved for use in infants younger than 6 months. Clinicians should identify all children aged 6 months through 18 years, especially those at increased risk for complications related to influenza, and should inform their parents when annual influenza immunization is due.

All 3 strains in the 2008 to 2009 influenza vaccines are different from the 2007 to 2008 vaccine strains on the basis of global surveillance of circulating influenza strains.

Healthy children aged 2 through 18 years can receive either trivalent inactivated influenza vaccine (TIV) or live-attenuated influenza vaccine (LAIV).

Age determines the number of influenza vaccine dose(s) to be administered, as follows:

Children aged at least 9 years who have not previously received the influenza vaccine require only 1 dose in their first season of immunization.

Any child younger than 9 years who is vaccinated against influenza for the first time should receive a second dose at least 4 weeks after the first.

Children younger than 9 years who received only 1 dose of influenza vaccine in the first season they were vaccinated should receive 2 doses of influenza vaccine the following season. This recommendation applies only to the influenza season after the first year that a child younger than 9 years is vaccinated against influenza.

For the 2008 to 2009 influenza season, oseltamivir or zanamivir are still the antiviral medications recommended for chemoprophylaxis or treatment. Because of widespread resistance among some circulating influenza A virus strains, and lack of efficacy against influenza B strains, amantadine or rimantadine should not be prescribed for treatment or chemoprophylaxis of influenza. Oseltamivir resistance has been reported but it is still very limited, so current antiviral treatment recommendations have not changed.

As soon as the influenza vaccine is available, it should be offered to all children, and immunization efforts should continue throughout the entire influenza season, even after influenza activity has been documented in a community. There may be more than 1 peak of activity during the same influenza season, which often extends into March and beyond. Immunization through May 1 can still protect vaccinees during that season and facilitates administration of a second dose of vaccine to children who require 2 doses during that season.

“Health care professionals, influenza campaign organizers, and public health agencies should cooperate to develop plans for expanding outreach and infrastructure to achieve the target immunization of all children 6 months through 18 years of age, beginning no later than the 2009-2010 influenza season,” the guidelines authors conclude. “Concerted effort among the aforementioned groups, plus vaccine manufacturers, distributors, and payers, also is necessary to appropriately prioritize administration of influenza vaccine whenever vaccine supplies are delayed or limited.”

Pediatrics. Published online October 1, 2008.