FluShield® (Influenza Virus Vaccine, Trivalent, Types A and B [Purified Subvirion]) is a sterile injectable for administration intramuscularly.

FluShield® is prepared from the allantoic fluids of chick embryos inoculated with a specific type of influenza virus. During processing, not more than 5 µg of gentamicin sulfate per mL is added. The harvested virus is concentrated, purified, then inactivated with formaldehyde.

The viral antigens contained in FluShield®, Trivalent (Purified Subvirion), are concentrated and refined by a column-chromatographic procedure. At the same time, addition of tri(n)butylphosphate and Polysorbate 80, USP, to the column-eluting fluids effects inactivation and disruption of a significant proportion of the virus to smaller subunit particles. The recovered subvirion (split-virus) suspension is freed of substantial portions of the disrupting agents by dialysis and of other undesirable materials by selective filtration through membranes of controlled pore size.

The viral antigen content has been standardized by immunodiffusion tests, according to current U.S. Public Health Service (PHS) requirements. Each dose (0.5 mL) contains the proportions and not less than the microgram amounts of hemagglutinin antigens (µg HA) representative of the specific components recommended for the 2000-2001 season: 15 µg HA of A/New Caledonia/20/99 (H1N1)-like, 15 µg HA of A/Panama/2007/99 (H3N2) (A/Moscow/10/99 [H3N2]-like), and 15 µg HA of B/Yamanashi/166/98 (B/Beijing/184/93-like).

The vaccine contains 1:10,000 thimerosal (mercury derivative; 25 µg mercury per 0.5 mL dose) as a preservative. Gentamicin sulfate is used during manufacturing, but is not detectable in the final product by assay procedures. The product appears as a slightly opalescent solution.

The administration of inactivated influenza virus vaccine each year before the influenza season is the single most important influenza-control measure. 1

The injection of antigens prepared from inactivated influenza virus stimulates the production of specific antibodies. Any protection afforded is only against those strains of virus from which the vaccine is prepared or closely related strains. With the passing of time, there may be major antigenic changes in the prevalent strains, or there may be continuous and progressive antigenic variation within a given virus subtype over time (antigenic drift), so that infection or immunization with one strain may not induce immunity to distantly related strains. Influenza A and B are the two types of influenza viruses that cause epidemic human disease. Influenza A viruses are further classified into subtypes on the basis of two surface antigens: hemagglutinin (H) and neuraminidase (N). A person's immunity to the surface antigens, especially hemagglutinin, reduces the likelihood of infection and the severity of disease if infection occurs. Influenza virus vaccine prevents illness in approximately 70% to 90% of healthy persons younger than 65 years when the antigenic match between vaccine and circulating viruses is close. 1 The PHS regularly reviews the antigenic characteristics of circulating strains in order to select those to be included in the contemporary vaccine.

Based upon the epidemiological data available through the early months of 2000 the Federal Government determined, after consultation with advisory groups, that the influenza virus vaccines to be distributed in 2000-2001 will be trivalent, including 15 µg HA each of strains that are antigenically similar to A/Moscow/10/99, A/New Caledonia/20/99, and B/Beijing/184/93.

FluShield® is indicated for active immunization against the specific influenza virus strains contained in the 2000-2001 formulation. FluShield® is recommended for 1) individuals 6 months of age or older at high-risk for developing complications from influenza virus infections which may result in hospitalization or death and for their medical care providers or household contacts and 2) anyone who wishes to reduce his or her chances of acquiring influenza. FluShield® should only be administered if it is prescribed by a healthcare professional whose license includes the prescribing of biologicals.

Elderly persons and persons with certain chronic diseases may develop lower postvaccination antibody titers than healthy young adults and thus may remain susceptible to influenza-related upper respiratory tract infections. However, even if such persons develop influenza illness despite vaccination, the vaccine has been shown to be effective in helping to prevent lower respiratory tract involvement or other secondary complications, thereby reducing the risk of hospitalization and death. 1

Guidelines for the use of influenza virus vaccine among different groups are given below.

Target Groups for Vaccination

Groups at increased risk for influenza-related complications:

  1. Persons 50 years of age or older (see PRECAUTIONS -- Geriatric Use ).
  2. Residents of nursing homes and other chronic-care facilities housing patients of any age with chronic medical conditions.
  3. Adults and children with chronic disorders of the pulmonary or cardiovascular systems, including asthma.
  4. Adults and children who have required regular 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).
  5. Children and teenagers (aged 6 months to 18 years) who are receiving long-term aspirin therapy and, therefore, might be at risk of developing Reye' syndrome after influenza infection.
  6. Women who will be in the second or third trimester of pregnancy during the influenza season. 1

Pregnant Women

Although animal reproductive studies have not been conducted, the prescribing healthcare professional should be aware of the recommendations of the Advisory Committee on Immunization Practices (ACIP), which are incorporated below. Influenza-associated excess mortality among pregnant women has not been documented, except during the pandemics of 1918-19 and 1957-58. However, because death-certificate data often do not indicate whether a woman was pregnant at the time of death, studies conducted during interpandemic periods may underestimate the impact of influenza in this population. Case reports and limited studies suggest that pregnancy may increase the risk for serious medical complications of influenza as a result of increases in heart rate, stroke volume and oxygen consumption, decreases in lung capacity, and changes in immunologic function. A study of the impact of influenza during 17 interpandemic influenza seasons demonstrated that the relative risk for hospitalization for selected cardiorespiratory conditions among pregnant women increased from 1.4 during weeks 14 to 20 of gestation to 4.7 during weeks 37 to 42 compared with rates among women who were 1 to 6 months postpartum. Women in their third trimester of pregnancy were hospitalized at a rate comparable to that of nonpregnant women who have high-risk medical conditions for whom influenza virus vaccine has traditionally been recommended. Using data from this study, it was estimated that an average of 1 to 2 hospitalizations among pregnant women could be prevented for every 1,000 pregnant women immunized. 1

On the basis of these and other data that suggest that influenza infection may cause increased morbidity in women during the second and third trimesters of pregnancy, the ACIP recommends that women who will be beyond the first trimester of pregnancy (>/=14 weeks' gestation) during the influenza season be vaccinated. Pregnant women who have medical conditions that increase their risk for complications from influenza should be vaccinated before the influenza season, regardless of the stage of pregnancy. A study of influenza immunization of more than 2,000 pregnant women have demonstrated no adverse fetal effects associated with influenza virus vaccine; however, more data are needed (see " PRECAUTIONS -- Pregnancy "). 1

Persons who can transmit influenza to persons at high risk:

Persons who are clinically or subclinically infected can transmit influenza virus to persons at high risk whom they care for or with whom they live. Some persons at high risk, e.g., the elderly, transplant recipients, and persons with acquired immunodeficiency syndrome (AIDS), can have a low antibody response to influenza virus vaccine. Efforts to help protect these members of high-risk groups against influenza might be improved by reducing the likelihood of influenza exposure from their caregivers. Therefore, the following groups should be vaccinated:

  1. Physicians, nurses, and other personnel in both hospital and outpatient settings.
  2. Employees of nursing homes and chronic-care facilities who have contact with patients or residents.
  3. Employees of assisted living and other residences for persons in high-risk groups.
  4. Providers of home care to high-risk persons (e.g., visiting nurses, volunteer workers).
  5. Household members (including children) of persons in high-risk groups. 1

Vaccination of Other Groups

General population:

Physicians should administer influenza virus vaccine to any person who wishes to reduce the likelihood of becoming ill with influenza caused by the strains incorporated into this year's vaccine. Persons who provide essential community services should be considered for vaccination to minimize disruption of essential activities during influenza outbreaks. Students or other persons in institutional settings (e.g., those who reside in dormitories) should be encouraged to receive vaccine to minimize the disruption of routine activities during epidemics. 1

Persons infected with human immunodeficiency virus (HIV):

Limited information exists regarding the frequency and severity of influenza illness among HIV-infected persons, but reports suggest that symptoms might be prolonged and the risk of complications increased for some HIV-infected persons. Influenza virus vaccine has produced substantial antibody titers against influenza in vaccinated HIV-infected persons who have minimal AIDS-related symptoms and high CD4+ T-lymphocyte cell counts. In patients who have advanced HIV disease and low CD4+ T-lymphocyte cell counts, however, influenza virus vaccine may not induce protective antibody titers; a second dose of vaccine does not improve the immune response for these persons.

Studies have examined the effect on influenza vaccination on replication of HIV type 1 (HIV-1). Although some studies have demonstrated a transient (i.e., 2- to 4-week) increase in replication of HIV-1 in the plasma or peripheral blood mononuclear cells of HIV-infected persons after vaccine administration, other studies using similar laboratory techniques have not indicated any substantial increase in replication. Deterioration of CD4+ T-lymphocyte cell counts and progression of clinical HIV disease have not been demonstrated among HIV-infected persons who receive vaccine.

Because influenza can result in serious illness and complications and because influenza vaccination may result in protective antibody titers, vaccination will benefit many HIV-infected patients. 1


The risk of exposure to influenza during foreign travel varies, depending on season and destination. Influenza can occur throughout the year in the tropics; the season of greatest influenza activity in the Southern Hemisphere is April through September. Because of the short incubation period for influenza, exposure to the virus during travel can result in clinical illness that begins during travel, an inconvenience or potential danger, especially for persons at increased risk for complications. Persons preparing to travel to the tropics at any time of year, or travel with large organized tourist groups containing persons from areas of the world where influenza viruses are circulating, or travel to the Southern Hemisphere from April through September should review their vaccination histories. If they were not vaccinated the previous fall or winter, they should consider influenza vaccination prior to travel. Persons in the high-risk categories especially should be encouraged to receive the most current vaccine. Persons at high risk who received the previous season' vaccine prior to travel should be revaccinated in the fall or winter with the current vaccine. 1

Immunization programs:

If this product is to be used in an immunization program sponsored by an organization WHERE A TRADITIONAL PHYSICIAN/PATIENT RELATIONSHIP DOES NOT EXIST, each participant (or legal guardian) should be made aware of the possible risks and adverse events that have been associated with the use of influenza virus vaccines, including the possible risk of a form of paralysis sometimes known as Guillain-Barré syndrome. Information about possible side effects and adverse events is presented below, and informed consent, preferably written, should be obtained from the intended recipient (or legal guardian) before vaccine administration. FluShield® is a prescription product and shall only be administered upon prescription by a healthcare professional who is licensed to prescribe biologicals. The prescribing healthcare professional should be familiar with the text of this insert, including the CONTRAINDICATIONS , , PRECAUTIONS , and ADVERSE REACTIONS sections.

Simultaneous Administration of Pneumococcal or Pediatric Vaccines

The target groups for influenza and pneumococcal polysaccharide vaccination overlap considerably. For persons at high risk who have not previously been vaccinated with pneumococcal polysaccharide vaccine, healthcare professionals should strongly consider administering pneumococcal and influenza virus vaccine concurrently. These vaccines can be administered at the same time at different sites without increasing side effects. 1 However, influenza virus vaccine is given annually, whereas pneumococcal polysaccharide vaccine is not. 2

Children at high risk for influenza-related complications can receive influenza virus vaccine at the same time as they receive other routine vaccinations, with administration at different sites recommended.

As with any vaccine, FluShield® may not protect 100% of individuals receiving the vaccine.


FLUSHIELD® SHOULD NOT BE ADMINISTERED TO INDIVIDUALS WITH A HISTORY OF HYPERSENSITIVITY (ALLERGY) TO CHICKEN EGG OR TO ANY COMPONENT(S) OF INFLUENZA VIRUS VACCINE, INCLUDING THIMEROSAL, WITHOUT FIRST CONSULTING A PHYSICIAN (see ADVERSE REACTIONS ). Before being vaccinated, persons known to be hypersensitive to egg protein or other components should be given a skin test or other allergy-evaluating test, using the influenza virus vaccine as the antigen. Persons with adverse reactions to such testing should not be vaccinated. Chemoprophylaxis may be indicated for prevention of influenza A in such persons. However, persons with a history of anaphylactic hypersensitivity to vaccine components but who are also at highest risk for complications of influenza infections may benefit from vaccine after appropriate allergy evaluation and desensitization. 1

Persons with a past history of Guillain-Barré syndrome (GBS) should not be given influenza virus vaccine (see ADVERSE REACTIONS ).

Persons with acute febrile illnesses usually should not be vaccinated until their symptoms have abated. However, minor illnesses with or without fever should not contraindicate the use of influenza virus vaccine, particularly in children with a mild upper respiratory tract infection or allergic rhinitis. 1,3

Patients with impaired immune responsiveness, whether due to the use of immunosuppressive therapy (including irradiation, large amounts of corticosteroids, antimetabolites, alkylating agents, and cytotoxic agents), a genetic defect, HIV infection, leukemia, lymphoma, generalized malignancy, or other causes, may have a reduced antibody response to active immunization procedures. Short-term (less than 2 weeks) oral corticosteroid therapy or administration via topical (skin or eyes) or inhalational routes, or intra-articular, bursal, or tendon injections is thought not to be immunosuppressive. 4 Inactivated vaccines are not a risk to immunocompromised individuals, although their efficacy may be substantially reduced. Because patients with immunodeficiencies may not have an adequate response to immunizing agents, they may remain susceptible despite having received an appropriate vaccine. If feasible, specific serum antibody titers or other immunologic responses may be determined after immunization to assess immunity. 3 Chemoprophylaxis may be indicated for high-risk persons who are expected to have a poor antibody response to influenza virus vaccine. 1

Healthcare professionals should prescribe and/or administer this product with caution to patients with a possible history of latex sensitivity since this packaging contains dry natural rubber.



Care should be taken by the healthcare professional for the effective use of this product.

  1. Prior to the administration of any dose of FluShield®, the patient, parent, or guardian should be asked about the personal history, family history, and recent health status of the vaccine recipient. The healthcare professional should ascertain previous immunization history, current health status, and occurrence of any symptoms and/or signs of an adverse event after previous immunization in order to determine the existance of any contraindication to immunization with FluShield® and to allow an assessment of benefits and risks.
  2. Influenza virus is remarkably capricious antigenically, and significant changes may occur from time to time. It is known definitely that influenza virus vaccine, as now constituted, is not effective against all possible strains of influenza virus. Any protection afforded is only against those strains of virus from which the vaccine is prepared or against closely related strains.
  3. Influenza virus vaccine often contains one or more antigens used in previous years. However, immunity declines during the year following immunization. Therefore, revaccination on a yearly basis is necessary to provide optimal protection for the current season. REMAINING 1999-2000 VACCINE SHOULD NOT BE USED.
  4. Before the injection of any biological, the healthcare professional should take all precautions known for the prevention of allergic or any other side reactions. This should include: a review of the patient' history regarding sensitivity; the ready availability of epinephrine injection (1:1000) and other appropriate agents used for control of immediate or delayed allergic reactions; and a knowledge of recent literature pertaining to use of the biological concerned, including the nature of side effects and adverse reactions that may follow its use.
  5. A separate sterile syringe and needle or sterile disposable unit should be used for each patient to prevent transmission of hepatitis or other infectious agents from one person to another. Reusable glass syringes and needles should be heat-sterilized. Needles should be disposed of properly and should not be recapped.
  6. Special care should be taken to prevent injection into or near a blood vessel or nerve.
  7. Vaccine sterility and stability cannot be assured if unit doses are withdrawn from the multidose vial and allowed to remain in syringes for longer than a few minutes prior to injection into patients.
  8. Guidance should be provided to the patient, parent, or guardian on measures to be taken should suspected adverse events occur, such as antipyretic measures for elevated temperatures and the need to report any suspected adverse occurrence to the healthcare professional.
  9. Healthcare professionals should administer FluShield® with caution to patients with a possible history of latex sensitivity, since this packaging contains dry natural rubber.

Drug Interactions

There have been conflicting reports 5 - 15 on the effects of influenza virus vaccine on the elimination of some drugs metabolized by the hepatic cytochrome P-450 system. Hypoprothrombinemia in patients receiving warfarin and elevated theophylline serum concentrations have occurred. Most studies have failed to show any adverse effects of influenza virus vaccine in patients receiving these drugs. Nevertheless, monitoring for possible enhanced drug effect or toxicity is indicated for those persons taking theophylline preparations or warfarin sodium.

Individuals receiving therapy with immunosuppressive agents (large amounts of corticosteroids, antimetabolites, alkylating agents, cytotoxic agents) may not respond optimally to active immunization procedures (see ).

As with other intramuscular injections, this product should be given with caution to a person on anticoagulant therapy.

Carcinogenesis, Mutagenesis, Impairment of Fertility

FluShield® has not been evaluated for its carcinogenic or mutagenic potential or for impairment of fertility.


Pregnancy Category C:

Animal reproduction studies have not been conducted with influenza virus vaccine. It is also not known whether influenza virus vaccine can cause fetal harm when administered to a pregnant woman or can affect reproductive capacity. Influenza virus vaccine should be given to a pregnant woman only if clearly needed. The benefits of preventing influenza-related complications versus the theoretical risk of fetal harm should be considered, and discussed with the patient before administering influenza virus vaccine to a pregnant woman. The ACIP states that, if used during pregnancy, administration of influenza virus vaccine after 14 weeks of gestation may be preferable to avoid coincidental association of the vaccine with early pregnancy loss 1 (see , Target Groups for Vaccination ).

Nursing mothers:

Influenza virus vaccine does not affect the safety of breastfeeding for mothers or infants. Breastfeeding does not adversely affect immune response and is not a contraindication for vaccination. 1

Geriatric Use

The effectiveness of influenza virus vaccine in preventing or attenuating illness varies, depending primarily on the age and immunocompetence of the vaccine recipient and the degree of similarity between the virus strains included in the vaccine and those that circulate during the influenza season. Studies have indicated that the effectiveness of influenza virus vaccine in preventing hospitalization for pneumonia and influenza among elderly persons living in settings other than nursing homes or similar chronic-care facilities ranges from 30% to 70% when a good match exists between vaccine and circulating viruses. 1

Among elderly persons residing in nursing homes, influenza virus vaccine is most effective in preventing severe illness, secondary complications, and death. Studies of this population have indicated that the vaccine can be 50% to 60% effective in preventing hospitalization and pneumonia and 80% effective in preventing death, even though efficacy in preventing influenza may often be in the range of 30% to 40% among the frail elderly. Achieving a high rate of vaccination among nursing home residents can reduce the spread of infection in a facility, thus preventing disease through herd immunity. Vaccination of healthcare workers in nursing homes also has been effective in reducing the impact of influenza among residents. 1

Pediatric Use

The safety and effectiveness of influenza virus vaccine in pediatric patients under 6 months of age have not been established. However, the ACIP recommends influenza vaccination in certain circumstances for persons 6 months of age or older (see , Target Groups for Vaccination and DOSAGE AND ADMINISTRATION ). 1


BECAUSE INFLUENZA VIRUS VACCINE CONTAINS ONLY NONINFECTIOUS VIRUSES, IT CANNOT CAUSE INFLUENZA. Occasional cases of respiratory disease following vaccination represent coincidental illnesses unrelated to influenza vaccination. 1

The most frequent side effect of vaccination is soreness at the vaccination site for up to 2 days. These local reactions generally are mild and rarely interfere with the ability to conduct usual daily activities. 1 With vaccines in general, it is not uncommon for patients to note at or around the injection site the following minor reactions: swelling or edema; pain or tenderness; redness, erythema, inflammation, or skin discoloration; induration or mass; or hypersensitivity reaction.

In addition, the following types of systemic reactions have occurred:

Fever, malaise, myalgia, and other systemic symptoms can occur following vaccination and most often affect persons who have had no exposure to the influenza virus antigens in the vaccine (e.g., young children). These reactions begin 6 to 12 hours after vaccination and can persist for 1 or 2 days. 1 One report of delayed anaphylaxis or delayed onset of severe asthma or hypersensitivity reaction in a known asthmatic after administration of FluShield® has been received. The reaction began approximately 6 hours following receipt of influenza virus vaccine and resulted in death within the next hour. Other systemic events that have been reported include: arthralgia, asthenia, chills, dizziness, headache, lymphadenopathy, pruritus, rash, vomiting, diarrhea, and pharyngitis. Recent placebo-controlled trials suggest that in elderly persons and healthy young adults, split-virus influenza vaccine is not associated with higher rates of systemic symptoms (e.g., fever, malaise, myalgia, and headache) when compared with placebo injections. 1 Other events that have been reported include angiopathy and vasculitis. 16-18

Immediate, presumably allergic, reactions such as hives, angioedema, allergic asthma, or systemic anaphylaxis occur rarely after influenza vaccination. These reactions probably result from hypersensitivity to some vaccine component--the majority of reactions are most likely related to residual egg protein. Although current influenza virus vaccines contain only a small quantity of egg protein, this protein can induce immediate hypersensitivity reactions among persons who have severe egg allergy. Persons who have developed hives, have had swelling of the lips or tongue, or experienced acute respiratory distress or collapse after eating eggs should consult a physician for appropriate evaluation to help determine if vaccine should be administered. Persons who have documented immunoglobulin E (IgE)-mediated hypersensitivity to eggs, including those who have had occupational asthma or other allergic responses due to exposure to egg protein, might also be at increased risk for reactions from influenza virus vaccine and similar consultation should be considered. The protocol for influenza vaccination developed by Murphy and Strunk may be considered for patients who have egg allergies and medical conditions that place them at increased risk for influenza-associated complications. 19 Hypersensitivity reactions to any vaccine component can occur. Although exposure to vaccines containing thimerosal can lead to induction of hypersensitivity, most patients do not develop reactions to thimerosal when administered as a component of vaccines even when patch or intradermal tests for thimerosal indicate hypersensitivity. When reported, hypersensitivity to thimerosal has usually consisted of local, delayed-type hypersensitivity reactions. 1 One study has reported a decrease in pulmonary function in some asthmatics who received influenza vaccine. 20 However, another study suggested that influenza vaccination was not associated with clinically significant asthma exacerbation or worsening of asthma symptoms in vaccines with acute exacerbation or with stable asthma. 21

There have been rare reports of Guillain-Barré syndrome (GBS) following receipt of influenza virus vaccine. GBS is an uncommon illness characterized by ascending paralysis which is usually self-limited and reversible. Though most persons with GBS recover without residual weakness, approximately 5% of cases are fatal. Before 1976, no association of GBS with influenza virus vaccine use was recognized.

Information from the Centers for Disease Control and Prevention ACIP Recommendations regarding GBS is incorporated below. Although the 1976 swine influenza virus vaccine was associated with an increased frequency of GBS, evidence for a causal relationship of GBS with subsequent vaccines prepared from other virus strains is less clear. However, obtaining strong evidence for a possible small increase in risk is difficult for a rare condition such as GBS, which has an annual background incidence of only 1 to 2 cases per 100,000 adults. During three of four influenza seasons studied from 1977 through 1991, the point estimates of the overall relative risk for GBS after influenza vaccination were slightly elevated but were not statistically significant in any of these studies. However, in a recent study of the 1992-1993 and 1993-1994 seasons, the overall relative risk for GBS was 1.7 (95% confidence interval=1.0 to 2.8, p=0.04) during the 6 weeks following vaccination, representing an excess of slightly more than one additional case of GBS per million persons vaccinated; the combined number of GBS cases peaked 2 weeks after vaccination. 22 The increase in the relative risk and the increased number of cases in the second week after vaccination may be the result of vaccination but also could be due to other factors (e.g., confounding or diagnostic bias) rather than a true vaccine-related risk. 1

Even if GBS were a true side effect of vaccination in the years after 1976, the estimated risk for GBS of slightly more than one additional case per million persons vaccinated is substantially less than that for severe influenza, which could be prevented by vaccination in all age groups, especially for persons aged >/=65 years and those who have medical indications for influenza vaccination. 1 During different epidemics occurring from 1972 through 1981, estimated rates of influenza-associated hospitalization have ranged from approximately 200 to 300 hospitalizations per million population for previously healthy persons aged 5 to 44 years and from 2,000 to >10,000 hospitalizations per million population for persons aged >/=65 years. During epidemics from 1972-73 through 1994-95, estimated rates of influenza-associated death have ranged from approximately 300 to >1,500 per million persons aged >/=65 years, who account for more than 90% of all influenza-associated deaths.

The average case-fatality ratio of GBS is 6% and increases with age. However, no evidence indicates that the case-fatality ratio for GBS differs among vaccinated and non-vaccinated persons.

Whereas the incidence of GBS in the general population is very low, persons with a history of GBS have a substantially greater likelihood of subsequently developing GBS than persons without such a history. Thus, the likelihood of coincidentally developing GBS after influenza vaccination is expected to be greater among persons with a history of GBS than among persons with no history of this syndrome. Whether influenza vaccination might be causally associated with this risk for recurrence is not known. 1 Avoiding subsequent influenza vaccination of persons known to have developed GBS within 6 weeks of a previous influenza vaccination seems prudent. Candidates for influenza virus vaccine should be made aware of the possible risks, including GBS, and the benefits of administration.

Other neurologic disorders not defined as GBS, including encephalopathies, facial paralysis, unspecified neuritis, encephalitis, peripheral nerve disease, brachial neuritis, optic neuritis, demyelinating disease, labyrinthitis and meningitis have been temporally associated with influenza vaccination. 23 Rarely, transverse myelitis has been reported. 24


The manufacturer and lot number of the vaccine administered should be recorded in the vaccine recipient' permanent medical record, along with the date of administration of the vaccine and the name, address, and title of the person administering the vaccine. Any adverse events following immunizations should be reported by the healthcare professional to the U.S. Department of Health and Human Services (DHHS).

The U.S. DHHS has established the Vaccine Adverse Event Reporting System (VAERS) to accept all reports of suspected adverse events after administration of any vaccine. The toll-free number for VAERS forms and information is 800-822-7967.



  9 years and older
0.5 mL (one dose)
  3 to 8 years
0.5 mL (1 or 2 doses) *
  6 to 35 months
0.25 mL (1 or 2 doses) *
* Two doses are recommended for children under 9 years who are receiving influenza virus vaccine for the first time. With the 2-dose regimen, allow 4 weeks or more between doses. Both doses are recommended for maximum protection.

For those under 13 years, only split-virus (subvirion) vaccine is recommended. Immunogenicity and reactogenicity of split- and whole-virus vaccines are similar in adults when used according to the recommended dosage. 1

Although influenza virus vaccine often contains one or more antigens used in previous years, immunity declines during the year following vaccination. Therefore, a history of vaccination in any previous year with a vaccine containing one or more antigens included in the current vaccine does NOT preclude the need for revaccination for the 2000-2001 influenza season to help provide optimal protection. REMAINING 1999-2000 VACCINE SHOULD NOT BE USED.

Influenza virus vaccine may be offered to high-risk persons presenting for routine care or hospitalization beginning in September, but not until new vaccine is available (see , Vaccination of Other Groups , Travelers for travel-related exceptions). Opportunities to vaccinate persons at high risk for complications of influenza should not be missed. In the United States, influenza activity generally peaks between late December and early March, and high levels of influenza activity infrequently occur in the contiguous 48 states before December. Although the optimal time for vaccination for high-risk persons usually is the period from October through mid-November, vaccine should continue to be offered to both children and adults up to and even after influenza virus activity is documented in a community. 1 In facilities such as nursing homes it is particularly important to avoid administering vaccine too far in advance of the influenza season because antibody levels may begin to decline within a few months of vaccination. 1

Children less than 9 years of age who have not been vaccinated previously should receive two doses with at least 1 month between doses to maximize the chance of a satisfactory antibody response to all three vaccine antigens. The second dose should be given before December, if possible.

Parenteral drug products should be inspected visually for particulate matter and discoloration prior to administration. The product should not be used if particulate matter or discoloration is found. The product appears as a slightly opalescent solution.

DO NOT INJECT INTRAVENOUSLY. Injections of FluShield® are recommended to be given intramuscularly. The recommended site is the deltoid muscle for adults and older children. 1 The preferred site for infants and young children is the anterolateral aspect of the thigh musculature. Because of lack of adequate evaluation of other routes in high-risk persons, the preferred route of vaccination is intramuscular whenever possible. Before injection, the skin over the site to be injected should be cleansed with a suitable germicide. After insertion of the needle, aspirate and wait to see if any blood appears in the syringe, which will help avoid inadvertent injection into a blood vessel. If blood appears, withdraw the needle and prepare for a new injection at another site.


Influenza Virus Vaccine, Trivalent, Types A and B, (Purified Subvirion), FluShield®, is available in vials of 5 mL as follows:

NDC 0008-0985-01


TUBEX® Sterile Cartridge-Needle Units, 0.5 mL fill in 1 mL size (25 gauge × 5/8 inch needle), in packages of 10 TUBEX as follows:

NDC 0008-0985-02


Store between 2°C to 8°C (36°F to 46°F). Potency is destroyed by freezing; do not use FluShield® that has been frozen.


  1. Prevention and control of influenza: Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR-April 14, 2000; 48 (RR-5) .
  2. Prevention of Pneumococcal Disease: Recommendations of the Advisory Committee on Immunization Practices (ACIP). MMWR-April 4, 1997; 46 (No. RR-8) .
  3. American Academy of Pediatrics: Report of the Committee on Infectious Diseases. 24th ed. Elk Grove Village, IL, American Academy of Pediatrics, 1997.
  4. Recommendations of the Advisory Committee on Immunization Practices (ACIP): Use of vaccines and immune globulins in persons with altered immunocompetence. MMWR-April 9, 1993; 42 (No. RR-4) .
  5. KRAMER, P., and McCLAIN, C.: Depression of aminopyrine metabolism by influenza vaccination. NEJM 1981; 305 : 1262.
  6. RENTON, K. et al: Decreased elimination of theophylline after influenza vaccination. Can Med Assoc J 1980; 123 : 288.
  7. GOLDSTEIN, R.S. et al: Decreased elimination of theophylline after influenza vaccination. Can Med Assoc J 1982; 126 : 470.
  8. BRITTON, L. and RUBEN, F.L.: Serum and theophylline levels after influenza vaccination. Can Med Assoc J 1982; 126 : 1375.
  9. FISCHER, R.G. et al: Influence of trivalent influenza vaccine on serum theophylline levels. Can Med Assoc J 1982; 126 : 1312-13.
  10. SAN JOAQUIN, V.H., REYES, S., AND MARKS, M.I.: Influenza vaccination in asthmatic children on maintenance theophylline therapy. Clin Pediatrics 1982; 21 : 724-6.
  11. STULTS, B. AND HASISAKI, P.: Influenza vaccination and theophylline pharmacokinetics in patients with chronic obstructive lung disease. West J Med 1983; 139 : 651-4.
  12. PATRIARCA, P.A. et al: Influenza vaccination and warfarin or theophylline toxicity in nursing-home residents. NEJM 1983; 308 : 1601.
  13. MEREDITH, C.G. et al: Effects of influenza virus vaccine on hepatic drug metabolism. Clin Pharm Ther 1985; 37 : 396-401.
  14. LIPSKY, B.A. et al: Influenza vaccination and warfarin anticoagulation. Ann Int Med 1984; 100 : 835-7.
  15. KRAMER, P. et al: Effect of influenza vaccine on warfarin anticoagulation. Clin Pharmacol Ther 1984; 35 : 416.
  16. HULL, T.P. and BATES, J.H.: Optic neuritis after influenza vaccination. Am J Ophthalmol 1997; 124(5) :703-704.
  17. KAWASAKI, A. et al: Bilateral anterior ischemic optic neuropathy following influenza vaccination. J Neuro-Ophthalmol 1988; 18(1) :56-59.
  18. KELSALL, J.T.: Microscopic polyangitis following influenza vaccination. J Rheumatol 1997; 24:7 .
  19. MURPHY, K.R. and STRUNK, R.L.: Safe administration of influenza vaccine in asthmatic children hypersensitive to egg proteins. J Pediatr 1985; 106 : 931-3.
  20. NICHOLSON, K. et al: Randomised placebo-controlled crossover trial on effect of inactivated influenza vaccine on pulmonary function in asthma. Lancet 1998; 351: 326-331.
  21. PARK, C.L. and FRANK, A.: Does influenza vaccination exacerbate asthma? Drug Safety 1998; 19 (2):83-88.
  22. LASKY, T et al: The Guillian Barré syndrome and the 1992-1993 and 1993-1994 influenza vaccines. NEJM 1998, 339(25) :1797-1802.
  23. RETAILLIAU, H. et al: Illness after influenza vaccination reported through a nationwide surveillance system, 1976-1977. Am J Epidemiol 1980; 111 : 170.
  24. BAKSHI, R. AND MAZZIOTTA, J.C.: Acute transverse myelitis after influenza vaccination: Magnetic resonance imaging findings. J Neuroimaging 1996; 6 : 248-250.

Manufactured by:

Wyeth Laboratories

A Wyeth-Ayerst Company

Marietta, PA 17547

U.S. Gov't. License No. 3

CI 6146-1                           Issued July 13, 2000