The Centers for Disease Control and Prevention (CDC) has made 2 significant changes to its annual recommendations for the prevention of influenza during the 2008-2009 flu season:1
- Annual vaccination is now recommended for all children ages 6 months through 18 years. (Last year, universal influenza vaccination was recommended only for children ages 6 months through 4 years.)
- The live attenuated influenza vaccine (LAIV) can now be used starting at 2 years of age.
Vaccinate older children
The CDC now recommends that 5- to 18-year-olds receive the influenza vaccine annually, and that this routine vaccination start as soon as possible, but no later than the 2009-2010 flu season. In other words, if routine vaccination can be achieved this year it is encouraged, but the CDC recognizes that it may not be possible to achieve in some settings until next year.
If family physicians do not incorporate routine vaccination for those ages 5 to 18 this year, they should still provide it for those in this age group who are at high risk for influenza complications, including those who:
- are on long-term aspirin therapy;
- have chronic pulmonary (including asthma), cardiovascular, renal, hepatic, hematological, or metabolic disorders;
- are immunosuppressed; or
- have disorders that alter respiratory functions or the handling of respiratory secretions.
Children who live in households with others who are at higher risk (children who are <5 years old, adults >50 years, and anyone with a medical condition that places him or her at high risk for severe influenza complications) should also be vaccinated.
LAIV is an option for even younger kids
Last year, the LAIV vaccine was licensed for children starting at age 5. Now, the LAIV can be given to healthy children starting at age 2, as well as to adolescents and adults through age 49. TABLE 1 compares the LAIV with the trivalent influenza vaccine (TIV).
Because LAIV is an attenuated live virus vaccine, some children should not receive it, including those younger than 5 years of age with reactive airway disease (recurrent wheezing or recent wheezing); those with a medical condition that places them at high risk of influenza complications; and those younger than 2 years of age. The TIV can be used in these children, starting at 6 months of age.
Regardless of whether a child receives LAIV or TIV, those younger than 9 years of age who are receiving influenza vaccine for the first time should receive 2 doses 4 weeks apart. If a child received only 1 dose in the first year, the following year he or she should receive 2 doses 4 weeks apart.
TABLE 1
LAIV vs TIV: How the 2 compare
| LAIV | TIV | |
|---|---|---|
| Route of administration | Intranasal spray | Intramuscular injection |
| Type of vaccine | Live attenuated virus | Killed virus |
| Approved age | 2-49 years | ≥6 months |
| Interval between 2 doses recommended for children 6 months to 8 years who are receiving influenza vaccine for the first time | 4 weeks | 4 weeks |
| Use with other live virus vaccines | Simultaneously or separated by 4 weeks | No restrictions |
| Use with influenza antiviral medication | Wait 48 hours after last antiviral dose to administer LAIV; wait 2 weeks after LAIV to administer antivirals | No restrictions |
| Contraindications and precautions | Chronic illness | Anaphylactic hypersensitivity to eggs |
| Chronic aspirin therapy | Moderate-to-severe illness (precaution) | |
| History of Guillain-Barre syndrome | ||
| Pregnancy | ||
| Caregiver to severely immune-suppressed individual | ||
| LAIV, live attenuated influenza vaccine; TIV, trivalent influenza vaccine. | ||
Coverage rates still need to improve
Influenza vaccine and antiviral agents continue to be underutilized. TABLE 2 lists estimated coverage with influenza vaccine for specific groups for whom immunization is recommended. It is particularly important that coverage rates for health care workers—which remain below 50%—be improved. Health care workers are at high risk of exposure to influenza and pose a risk of disease transmission to their families, other staff members, and patients. Family physicians should ensure that they and their staff are vaccinated each year.
Missed opportunities. Many patients for whom influenza vaccine is recommended fail to receive the vaccine because of missed opportunities. Physicians should offer the vaccine starting in October (or as soon as the vaccine supply allows) and continue to offer and encourage it through the entire flu season. Peak influenza activity can occur as late as April and May and occurs after February on average of 1 in every 5 years.
TABLE 2
Immunization is recommended, but what were the coverage rates?*
| POPULATION GROUP | COVERAGE |
|---|---|
| Age 6-23 months | 32.2% |
| Age 2-4 years | 37.9% |
| Age ≥65 years | 65.6% |
| Pregnant women | 13.4% |
| Health care workers | 41.8% |
| Ages 18-64 years with high-risk conditions | 35.3% |
| * Influenza vaccination coverage is for the most recent year surveyed (2005-06 or 2006-07). | |
Autism concerns persist among parents
Despite clear scientific evidence that neither vaccines nor thimerosal preservative cause autism, some parents remain concerned. Some states have passed laws prohibiting the use of any thimerosal-containing vaccines and some parents may request thimerosal-free vaccines. TABLE 3 lists all the influenza vaccines and their thimerosal content.