Jun 29, 2006 (CIDRAP News) Federal health officials have made it official that toddlers aged 2 through 4 years should be immunized against influenza each year, adding millions of people to the groups included in flu vaccination recommendations.
The Centers for Disease Control and Prevention (CDC) published its annual flu prevention and control recommendations online yesterday as a lengthy early-release article in Morbidity and Mortality Weekly Report.
As expected, the CDC adopted the February recommendation of the Advisory Committee on Immunization Practices (ACIP) to expand the pool of toddlers who should be immunized to include 2-, 3-, and 4-year-olds (see link below to Feb 23 CIDRAP News article). The ACIP recommendation was influenced by reports that children in the expanded age-group are almost as likely as those aged 6 months to 2 years to visit physicians and emergency rooms for flu treatment. The recommendation for immunization of 6- to 23-month-olds has been in place since 2004.
In February, the CDC estimated that the recommendation regarding 2-, 3-, and 4-year-olds would increase the number of people included in flu immunization recommendations by more than 16 million, including 5.3 million children and 11.4 million caregivers and contacts.
The ACIP emphasized that all children aged 6 months to 9 years who have never been vaccinated should receive two doses of vaccine. Those who receive a trivalent inactivated influenza vaccine (TIV, or injectable vaccine) should have a booster 1 month or longer after the initial dose, before the onset of influenza season.
Children aged 5 to 9 years who receive the live attenuated influenza vaccine (LAIV)the intranasal vaccineshould have a second dose 6 to 10 weeks after the first. Any child age 6 months to 9 years who received just one dose the previous year need only get one dose during the current flu season.
The CDC projects that about 100 million doses of influenza vaccine will be available this seasonabout 16% more than in 2005-06. If a new vaccine is licensed in 2006, an additional 15 million to 20 million doses might be available. (The Food and Drug Administration is currently reviewing a license application for a GlaxoSmithKline flu vaccine called FluLaval. The vaccine is marketed in Canada under the name Fluviral. It was previously made by ID Biomedical, a Canadian company that was bought by GlaxoSmithKline last December.)
Though the intranasal vaccine costs more than injectable vaccines, the CDC report says the price difference has decreased for the coming flu season.
To ensure optimal use of the vaccine supply, the CDC recommends that healthcare providers expand outreach efforts to boost the number of people vaccinated and develop contingency plans for timing and prioritizing if the vaccine supply is delayed or reduced. Though optimal vaccination timing is early fall, the CDC emphasizes that later immunization timingeven after Decemberis still useful because flu outbreaks peak from December through early March.
Besides children aged 6 months through 4 years, groups for whom flu immunization is recommended include the following:
- Children and adolescents (6 months through 18 years) who are receiving long-term aspirin therapy
- Women who will be pregnant during the flu season
- Adults and children who have asthma, other chronic respiratory or cardiovascular conditions, or any condition that can impair respiratory function
- Adults and children under treatment for chronic metabolic disorders, kidney problems, hemoglobinopathies, or immunodeficiency
- Residents of nursing homes and other chronic-care facilities
- People age 50 and older
In addition, to help protect vulnerable groups, the CDC recommends immunization for healthcare workers and household contacts and caregivers of children aged 0 to 59 months and people at high risk for severe flu complications.
In its current recommendations, the CDC continues to voice concern about resistance of common influenza A strains to the antiviral drugs amantadine and rimantadine. (See Jan 14, 2005, CIDRAP News article.) The agency advises physicians not to use the two medications until viral susceptibility questions have been answered regarding this seasons circulating influenza strains. The report notes that viral resistance to the neuraminidase inhibitors zanamivir and oseltamivir is less frequent, but that tests for detecting clinical resistance to the drugs are being developed.
CDC. Prevention and control of influenza: Recommendations of the Advisory Committee on Immunization Practice (ACIP). MMWR 2006 Jun 28;55:1-41 [Full text]
Feb 23, 2006, CIDRAP News story "ACIP endorses flu shots for 2-, 3-, and 4-year-olds"
Jan 26, 2006, CIDRAP News story "Record flu vaccine supply expected next season"
Jan 14, 2005 CIDRAP News story "CDC: Resistance makes 2 older flu drugs ineffective"