ATLANTA — Influenza vaccine recommendations for the 2005-2006 season will seek to minimize disruption in the event of another shortage and will strongly urge annual vaccination of health care workers against influenza.
A risk-based prioritization scheme for the inactivated (injectable) influenza vaccine and a stronger recommendation for immunization of health care workers with the live attenuated influenza vaccine (LAIV, or FluMist) are among the proposed changes to the yearly influenza vaccine statement discussed at a meeting of the Centers for Disease Control and Prevention's Advisory Committee on Immunization Practices.
There is no concrete information to suggest that there will be flu vaccine supply problems again next fall, but disruptions have occurred in four of the five previous seasons. Contributing factors have included production issues and regulatory actions. In addition, two manufacturers have left the market.
Thus “there is uncertainty about the 2005-2006 vaccine supply,” Keiji Fukuda, M.D., of the CDC's influenza branch, told the committee.
Although the final language was still being worked out at press time, ACIP voted in principle to support a three-tiered prioritization system in which high-risk groups are ranked based on rates of influenza-associated mortality and hospitalization in the United States. (See box.)
The tiering scheme applies only to the inactivated influenza vaccine, and the document is expected to contain a strong recommendation for the preferential use of LAIV for healthy persons aged 5-49 years—particularly health care workers—in the event of a shortage.
During periods of vaccine shortfall, persons listed in tier 1 should be vaccinated preferentially, followed by tiers 2 and 3. The subdivisions within tier 1 would be used only in the unlikely event that the local vaccine supply is extremely limited. Should that occur, state and local health officials should vaccinate the two populations in tier 1A—those aged 65 and older with comorbid conditions and long-term care facility residents—before all others.
In all other vaccine shortfall situations, populations falling into tiers 1A, 1B, and 1C should be considered equivalent and should be vaccinated simultaneously. Eligible individuals in tiers 1C, 2, and 3 should be encouraged to receive LAIV (those in tier 1C—health care personnel and close contacts of children less than 6 months of age—could receive either the injectable vaccine or LAIV, depending upon supply circumstances).
The committee also voted to include much stronger language about immunization of health care workers overall, regardless of vaccine supply status. Among the likely recommendations are that campaigns be organized to encourage workplace efforts to improve immunization rates among health care workers, and that such rates be regularly measured and reported.
“Giving the influenza vaccine to health care workers keeps them at work. It becomes a quality issue,” said ACIP member Jon S. Abramson, M.D. “When you increase the number of patients a nurse has to take care of [due to absenteeism], it affects patient outcome.”
Proposed Tiering in the Event of an Influenza Vaccine Shortage
Group 1A
▸ Aged 65 years and older with comorbid conditions.
▸ Long-term care facility residents.
Group 1B
▸ Pregnant women.
▸ Aged 2-64 years with comorbid conditions.
▸ Aged 65 years and older without comorbid conditions.
▸ Aged 6-23 months.
Group 1C
▸ Health care personnel.
▸ Close contacts of children less than 6 months of age.
Group 2
▸ Contacts of high-risk children and adults.
▸ Healthy persons aged 50-64 years.
Group 3
▸ Aged 2-49 years without high-risk conditions.
Source: Dr. Fukuda