On January 14, 2005, the Food and Drug Administration (FDA) approved meningococcal polysaccharide diphtheria toxoid conjugate vaccine (Menactra), a vaccine for protection against meningococcal meningitis. Menactra is an intramuscularly administered vaccine that contains antigens to four serogroups (A, C, Y, and W-135) of the Neisseria meningitidis bacteria. Meningococcal infections occur both sporadically and in local outbreaks. Infants have the highest rate of N. meningitidis-caused meningitis, but the rates for adolescents and young adults have increased in the past decade. Although the risk is still considered low, college freshmen living in dormitories are at increased risk of meningococcal disease.
Indications
Menactra is indicated for active immunization of adolescents and adults 11 to 55 years of age for the prevention of meningococcal disease caused by N. meningitidis serogroups A, C, Y, and W-135. 1 The vaccine is not indicated for prevention of meningitis caused by N. meningitidis serogroup B or other microorganisms. Menactra is a preventative vaccine and is not indicated in the treatment of meningococcal infections.
Other people who should get the vaccine include:
* United States military recruits
* People who might be affected during an outbreak of certain types of meningococcal disease
* Anyone traveling to, or living in a part of the world where meningococcal disease is common, such as West Africa
* Anyone who has a damaged spleen, or whose spleen has been removed
* Anyone who has terminal complement component deficiency
The Advisory Committee on Immunization Practices (ACIP) is a part of the United States' Centers for Disease Control and Prevention (CDC) and publishes recommendations regarding immunization practices. The committee issued recommendations in 2000 regarding the use of meningococcal vaccines for the college-aged population (see Sidebar: "Recommendations for Use of Meningococcal Polysaccharide Vaccine in College Students"). These recommendations may be found at the CDC Web site: http://www.cdc.gov/mmwr. In March 2005, ACIP released revised recommendations regarding this vaccine. This committee now recommends routine vaccination of young adolescents with the meningococcal vaccine at the pre-adolescent visit (11 to 12 years old).
The risk of meningitis is greatest for college freshmen living in dormitories, and the ACIP recommends providers inform these students and their parents about meningococcal disease and the benefits of vaccination. 3 However, because other microbes may be responsible for causing meningitis, and the efficacy of vaccines is < 100%, vaccination with Menactra does not fully eliminate risk. 4
Mechanism of Action
Menactra contains the capsular polysaccharides of serogroups A, C, Y, and W-135 for N. meningitidis. After administration of the vaccine, bactericidal antibodies are produced and confirm protection from invasive meningococcal disease specific to these serogroups. Antibody levels typically decline after 2 to 3 years, but recommendations for revaccination have not been determined. As an intramuscular vaccine, hepatic or gastrointestinal metabolism is not a relevant factor in the vaccine's mechanism of action.
Contraindications/Precautions
Menactra is contraindicated in persons with a known hypersensitivity to any components of the vaccine, including diphtheria toxoid. Because the vaccine is drawn from a vial through a natural rubber latex stopper, it is also contraindicated in individuals with a known latex-sensitivity. 1
Menactra is a Pregnancy Category C, and there are no adequate studies available using this vaccine in pregnant women.
The use of this vaccine in children younger than 11 years of age or adults older than 55 years of age has not been established. 1 Persons with risk of hemorrhage due to disease (i.e. hemophilia or thrombocytopenia) or on anticoagulation therapy should not receive Menactra. If the decision is made to administer Menactra in these people, it should be given with caution, and steps should be taken to avoid the risk of bleeding or hematoma formation following injection. 1
Adverse Reactions
The most commonly reported adverse reactions for Menactra according to primary safety studies were pain, headache, fatigue, malaise, and arthralgia. These responses were typically reported as being mild in intensity. 1 Other adverse reactions included induration, diarrhea, redness, swelling, and anorexia. No serious adverse events in the study populations were reported other than those consistent with expected events. 1
Menactra is a single injection administered intramuscularly, preferably in the deltoid area.
Dosage and Administration
Menactra is supplied in one-dose vials and a single injection of 0.5 mL is administered intramuscularly, preferably in the deltoid area. As with other intramuscular injections, the routine steps of cleaning the site and aspiration for blood before injection should be followed. The vaccine should not be administered intravenously, subcutaneously, or intradermally.
Consult prescriber information for studies done on concomitant administration of Menactra with other vaccines. 1 Menactra should not be mixed with other vaccines in the same syringe, and each vaccine should be administered at a separate site. 1
Special Instructions
Menactra must be stored between 35[masculine ordinal indicator]F to 46[masculine ordinal indicator]F and not allowed to freeze. The long-term efficacy of the vaccine or the need for a booster dose has not been determined.
The United States Department of Health and Human Services has a Vaccine Adverse Event Reporting System where practitioners and vaccine recipients are encouraged to report any potential adverse events related to vaccine administration. The form for reporting vaccine-related adverse events may be obtained from http://www.vaers.org.
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