Developing a Comprehensive Public Health Approach to Influenza

Vaccination Background and History

In the United States, influenza is responsible for more than 200,000 hospitalizations and 36,000 deaths averaged each year.1 Widespread use of influenza vaccine among persons targeted for immunization can reduce this burden. The Government Accountability Office (GAO, formerly the General Accounting Office) previously concluded that problems at one or more manufacturers of influenza vaccine could significantly upset the production and annual delivery of U.S. vaccine, as only two suppliers, Aventis Pasteur and Chiron Corporation, provide the country with over 95 percent of its total supply.2,3 Further, the number of companies selling influenza vaccine in the United States has steadily diminished since 1976.

Inactivated influenza vaccine, administered by injection, is the principal influenza vaccine currently in use. The first live attenuated influenza vaccine, delivered
intranasally, was approved by the Food and Drug Administration in June 2003 and has limited indications.4,5 Despite the recommendation of the Centers for Disease Control and Prevention that approximately 185 million Americans fall into at-risk and other target groups that should receive inactivated influenza vaccine annually, vaccination against influenza during recent flu seasons has fallen short when less than half that number of Americans were vaccinated.6 Broad vaccination against seasonal influenza has become problematic because the vaccine supply of the United States has not been adequate due to manufacturing, safety and quality control difficulties at vaccine manufacturing plants of companies with a contract with the United States Department of Health and Human Services to produce vaccine for domestic use.7

Current Infrastructure to Address Influenza Vaccine Shortages

The delivery system for influenza vaccines in the United States is highly decentralized. Vaccine distribution occurs primarily in the private sector with little influence by state and local health departments on actual vaccine ordering, delivery or administration. The vaccine manufacturers determine the number of vaccine doses to be produced each year by attempting to anticipate demand. This decision is often based upon prior vaccine usage coupled with any changes in vaccine recommendations (e.g., universal vaccination of children 6-23 months of age). The companies may consult CDC; however, CDC has no authority to require a set amount of production. CDC's major influence is through recommendations for use by the Advisory Committee on Immunization Practices. CDC can, however, contract for production of influenza vaccine reserves.

This lack of centralized oversight has led to difficulty in doing advanced planning for or providing advanced direction about redistribution when there is a shortage of inactivated influenza vaccine. Further, no current mechanism exists for the federal government to ensure that immunization priority is given to individuals in identified high-risk groups or that vaccination stocks are equitably distributed. In times of shortages or "spot" shortages, particularly those entities that do not order vaccine in mass quantities local and state health departments and physician's offices have had difficulty acquiring influenza vaccine.8

As a first step, in 2001, the GAO recommended the CDC, to better prepare for influenza vaccine shortages, should formulate voluntary guidelines for vaccine distribution in the event of a future vaccine delay or shortage.9 Despite the efforts of CDC to intervene in the national crisis, the FDA on Oct. 9, 2004, invoked the "emergency medical reasons" provision (Section 503(c)(3)(B)(iv) of the Food, Drug, and Cosmetic Act), which allows for a hospital or health care entity to redistribute influenza vaccine to alleviate vaccine shortages.10 Without centralized federal oversight, there is no guarantee that the redistributed vaccines will reach those members of high-risk groups most in need of the vaccine.

Mechanisms to Ensure Vaccine Supply and Distribution

Manufacturing inactivated influenza vaccine relies on growing viruses in millions of fertilized chicken eggs and generally takes six-to-eight months to complete. This causes manufacturers to predict demand and federal and global officials to decide which three strains to include in the vaccine far in advance of the flu season. The result has been uncertainty as to whether the annual influenza vaccine supply will meet the demand for the vaccine.11Also, this lag time in manufacturing makes the supply of influenza vaccine for U.S. distribution vulnerable to antigenic shift and antigenic drift.12 This, along with unpredictable demand and a decentralized distribution system, complicates the ability of the United States to protect itself against epidemics and a future influenza pandemic.

The American Public Health Association has approved several policy resolutions (83-02; 87-06; 89-06; 91-02; and 2000-23) that address the immunization of children and adults and provide for their protection from all vaccine-related reactions. The Association is supportive of the decision to include influenza vaccine in the federal Vaccine Injury Compensation Program, retroactive for eight years, which parallels the conclusions of APHA policy 83-02.

Current U.S. Capacity to Respond to Pandemic Influenza

The National Strategy for Pandemic Influenza and the HHS Pandemic Influenza
Plan focuses on assuring and expanding influenza vaccine production capacity; increasing influenza vaccination use; stockpiling influenza antiviral drugs in the Strategic National Stockpile (SNS); enhancing U.S. and global disease detection and surveillance infrastructures; expanding influenza-related research; supporting public health planning and laboratories; and improving health care system readiness at the community level.13,14

Although the HHS plan defines the roles of federal, state and local health and hospital officials and vaccine-producing companies during pandemic situations, neither the plan nor the National Strategy addresses the inadequacy of resources of state and local health departments and governments for fulfilling their assigned roles. Although the plan calls for widespread vaccination of individuals against pandemic flu, it does not include a federally funded compensation program for those who become ill or are injured, disabled or die as a result of receiving the vaccine.

Therefore, the American Public Health Association:

References: