Dear Health Care Provider:

The Centers for Disease Control and Prevention (CDC) is asking your assistance in implementing the recommendations of the Advisory Committee on Immunization Practices (ACIP) for influenza vaccination. During the 2000-2001 influenza season, manufacturing problems resulted in a significant delay of influenza vaccine availability. This delay was due to a combination of factors including problems some manufacturers had in growing one of the virus strains used in vaccine and problems two manufacturers had with good manufacturing practices. Ultimately, one manufacturer withdrew from the market and did not distribute any vaccine. To make up for possible shortfalls of influenza vaccine, CDC contracted with one manufacturer to extend their production period and produce up to 9 million doses of additional influenza vaccine that was available in December 2000. As a result, flu vaccine supplies were approximately what was distributed in prior years; however, a substantial amount of vaccine reached providers much later
than usual.

Because influenza vaccine is newly produced for each influenza season, numerous factors may affect the manufacturers' vaccine production and distribution. If some manufacturers are delayed in getting their vaccine to the providers, there will be uneven distribution of the vaccine with providers who ordered from some manufacturers receiving vaccine later than providers who ordered from other manufacturers. Further, providers who order late may receive vaccine late. Providers who order from third party distributors will be dependent upon which manufacturer is supplying that distributor. Manufacturers' current projections indicate that influenza vaccine supply should be similar to prior seasons. However, we will not know for certain until substantially later this year as manufacturers gain experience with production of this year's viral strains. Therefore, we ask you to develop contingency plans now so immunization efforts are better targeted to immunize those at highest risk first, in the event a delay or
shortage occurs.

In preparation for this year's influenza season, CDC strongly encourages those of you with high- risk patients to order vaccine now, rather than waiting to order later in the spring, summer, or fall. Ordering now will help manufacturers and distributors gauge demand and improve the opportunity to immunize high-risk individuals as early in the season as possible.

CDC published the ACIP recommendations, "Prevention and Control of Influenza," in the April 20, 2001, Morbidity and Mortality Weekly Report (MMWR). (The MMWR can be found at www.cdc.gov.) Enclosed is a listing of individuals recommended to receive influenza vaccine.

An important change in the ACIP recommendations is to extend the optimal time for vaccinating high-risk individuals from mid-November to the end of November. In addition, ACIP recommends that efforts should continue to vaccinate individuals through December and later, even if influenza is occurring in the community. During 19 influenza seasons from 1982 to 2000, influenza peaked in January or later in 15 seasons and in February or later in 10. This indicates administration of vaccine in December or even January should have an impact in most influenza seasons.

The ACIP recommendations also suggest that persons planning substantial organized vaccination campaigns consider scheduling these events after mid-October, to minimize the need for cancellations because vaccine is unavailable. We would also ask that employee-based campaigns, which primarily immunize a healthy, younger population, consider postponing their campaigns even later, particularly if there is a significant delay or shortage of vaccine, so that high-risk individuals may be immunized first.

CDC will continue to work closely with the FDA, vaccine manufacturers, State and local health officials, and other partners to share information regarding the influenza vaccine supply as it becomes available. We appreciate your efforts to maximize influenza vaccine to prevent influenza complications.

Sincerely,

Walter A. Orenstein, M.D.
Assistant Surgeon General
Director
National Immunization Program

 

Enclosure

 

ADVISORY COMMITTEE ON IMMUNIZATION PRACTICES RECOMMENDATIONS FOR INFLUENZA VACCINATION

TARGET GROUPS FOR VACCINATION

Persons at Increased Risk For Complications:

• persons aged 65 years;
• residents of nursing homes and other chronic-care facilities that house persons of any age who have chronic medical conditions;
• adults and children who have chronic disorders of the pulmonary or cardiovascular systems, including asthma;
• adults and children who have required medical follow-up or hospitalization during the preceding year because of chronic metabolic diseases (including diabetes mellitus), renal dysfunction, hemoglobinopathies, or immunosuppression (including immunosuppression caused by medications or by human immunodeficiency virus);
• children and teenagers (aged 6 months to 18 years) who are receiving long-term aspirin therapy and therefore might be at risk for developing Reyes syndrome after influenza infection; and
• women who will be in the second or third trimester of pregnancy during the influenza season.

Persons Aged 50-64 Years

• Vaccination is recommended for persons aged 50-64 years because this group has an increased prevalence of persons with high-risk conditions. Persons aged 50-64 years without high-risk conditions also receive benefit from vaccination in the form of decreased rates of influenza illness, decreased work absenteeism, and decreased need for medical visits and medication, including antibiotics.

Persons Who Can Transmit Influenza to Those at High Risk

• physicians, nurses, and other personnel in both hospital and outpatient-care settings, including emergency response workers
• employees of nursing homes and chronic-care facilities who have contact with patients or residents
• employees of assisted living and other residences for persons in groups at risk o persons who provide home care to persons in groups at
  high risk
• household members (including children) of persons in groups at high risk