How the Delayed Distribution: Recent Patterns in Influenza Vaccine Production and Distribution
Among the current manufacturers, Aventis Pasteur and Wyeth Lederle produce influenza vaccine in manufacturing plants located in the U.S. while Evans Vaccines produces influenza vaccine in the United Kingdom, but distributes a percentage of their production in the U.S. In most years, more doses of influenza vaccine are produced by manufacturers, and are released by the FDA, than are distributed. For example, in 1999, 2000, and 2001, respectively, the manufacturers produced combined totals of approximately 77.2 million, 77.9 million, and 87.7 million doses of influenza vaccine while distributing, in those same years, an estimated 76.7 million, 70.4 million, and 77.7 million doses (Figure 2). However, as was previously discussed, the timing of the release of those doses differed significantly by year.
Recent Patterns in Influenza Vaccination Coverage and Usage
Patterns of influenza vaccine use can be estimated from the National Health Interview Survey (NHIS), a national household survey representative of the civilian, noninstitutionalized U.S. population. A randomly selected adult in each participating household is asked if he or she received a flu shot during the past 12 months. We used data from adults interviewed during the first quarter of each year to approximate influenza vaccine coverage for the preceding year’s fall/winter influenza seasons. Based on first quarter NHIS data, influenza vaccination coverage increased more than two-fold among persons 18 years of age or older from 1988-1989 to the 1999-2000 influenza seasons (Figure 3). Among persons 65 years of age or older, influenza vaccination coverage levels first exceeded the national Healthy People 2000 objective of 60°% by the 1996-1997 influenza season, subsequently increased about 1% point per season to 68% in the 1999-2000 season, and then dropped to 63% in the 2000-2001 season, probably as a result of the influenza vaccine supply delays. At the current rate of increase in vaccination coverage among the elderly, the Healthy People 2010 influenza vaccination coverage objective for the elderly of 90% will not be met.
eriacta tablets
Figure 2. Number of influenza vaccine doses produced, distributed, and used per influenza season, 1999-2001, U.S.
Vaccination coverage levels have also increased to about 46% in the 1999-2000 season among persons 50-64 years of age with high-risk medical conditions and to about 28% among persons 18-49 years of age with high-risk medical conditions (Table 1). Nonetheless, vaccination coverage levels in these groups remain far below the target level of 60% set by the 2000 and 2010 Healthy People objectives. Among adults aged 18 to 49 without identified high-risk conditions, the use of influenza vaccine is also low, but it has increased substantially from 12.5% in the 1996-1997 influenza season to 17.3% in the 1999-2000 season.
canadian pharmacy support net
Table 1 Estimated Vaccine Use Among Persons at High Risk for Complications From Influenza, Other Target Groups, and Other Persons, 1999-2000 Influenza Season, U.S.
| Group | Population (millions)1 | Percent Vaccinated2 | Vaccine Doses Used3 (millions) |
| High Risk | 74.9 | 47.3% | 35.4 |
| 65+ yrs | 35 | 68.1% | 23.8 |
| Chronic Illness4 | |||
| 50-64 yrs | 12.3 | 45.5% | 5.6 |
| 18-49 yrs | 18 | 27.5% | 5 |
| 6 mo. to 17 yrs | 7.6 | 10% | 0.8 |
| Pregnant Women6 | 2 | 10% | 0.2 |
| Other (Healthy) Target Groups | 76.6 | 25.7% | 19.7 |
| Health Care Workers <65 yrs7 | 7 | 42.3% | 3 |
| Other persons 50-64 yrs | 27.6 | 32.9% | 9.1 |
| Household Contacts (<50 yrs) | 42 | 18% | 7.6 |
| Of those at high risk8 | |||
| Non-target persons <50 yrs | 127.9 | 13% | 16.6 |
| Total, persons aged >5 mo. | 279.4 | 25.7% | 71.7 |
In the 1999-2000 influenza season, approximately one-half of all administered influenza vaccine doses went to groups of persons at high risk for complications from influenza, i.e., those over 65 years of age and younger persons with a high-risk medical condition, while another one-fourth was administered to other target groups, i.e., those 50 to 64 years of age or those under 50 who were in close contact with high-risk persons. The remaining vaccine was utilized by healthy persons under 50 years of age (Table 1).
Expanding Recommendations for Influenza Vaccine Use
An important consideration related to increasing influenza vaccine use is the recent expansion of groups targeted for influenza vaccination by the Advisory Committee on Immunization Practices (ACIP), an advisory group to CDC. The ACIP has a central role in developing U.S. vaccination policy and has long targeted influenza vaccination efforts toward groups at elevated risk for developing severe complications from influenza infection, as well as persons in close contact with the “high-risk” groups. The “high-risk” groups include persons over 65 years of age, as well as younger persons with one or more medical conditions (including a chronic pulmonary or cardiac condition, diabetes, an immunosuppressive state or condition and the second or third trimester of pregnancy). The “close contact” group includes health care workers and family members. In 2000, the ACIP also began recommending influenza vaccination of all persons 50 to 64 years of age, primarily to increase vaccination levels among persons in this age group with high-risk medical conditions. buy antibiotics no prescription
Figure 3. Estimated influenza vaccination coverage by age and risk groups, 1988-1989 to 2000-2001 influenza seasons, U.S.
The combined number of people for whom influenza vaccination is currently recommended is approximately 152 million people, including 75 million in the high-risk category and 77 million in the other targeted groups (Table 1). In 2002, ACIP also began encouraging annual influenza vaccination for all children six through 23 months of age and their close contacts.
erectalis 20 mg
In practice, the number of persons for whom influenza vaccination is recommended or encouraged is much greater than the current levels of vaccine demand. Nonetheless, the continued efforts of ACIP and other groups to expand influenza vaccine usage, coupled with important demographic trends such as the rapidly growing numbers of elderly persons suggest that the demand for influenza vaccine could increase substantially in the future.
