Video Transcript: Smallpox Vaccine Administration
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Contraindications and Precautions to Vaccination and Screening Potential Vaccine Candidates
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In this segment of the program, we will discuss contraindications and precautions to the administration of smallpox vaccine. These contraindications and precautions are applicable for situations of nonemergency use of smallpox vaccine.
In an outbreak, for persons exposed or potentially exposed to a person with smallpox, there are no contraindications to vaccination.
Smallpox vaccine contains live vaccinia virus, which is administered into the superficial layers of the skin. A successful vaccination produces a lesion on the skin that contains vaccine virus for up to 3 weeks. The vaccine virus can be transmitted to household and other close contacts. So, in the absence of smallpox cases, candidates for vaccination must be screened for contraindications very carefully. Certain medical conditions in the person's household contacts must also be considered as contraindications for vaccination.
As with all vaccines, smallpox vaccine is contraindicated for persons who have experienced a serious allergic reaction to a prior dose of vaccine, or to a vaccine component. By serious allergic reaction, we mean anaphylaxis or symptoms of an anaphylaxis-like reaction, such as generalized urticaria, wheezing, or difficulty breathing.
In addition to live vaccinia virus, reconstituted Dryvax vaccine contains trace amounts of the antibiotics polymyxin B, streptomycin, tetracycline, and neomycin. It also contains phenol as a preservative. People with serious allergy to any of these products should not be vaccinated. The newer cell culture vaccines do not contain antibiotics. No smallpox vaccine available in the United States contains penicillin.
People with significant immunosuppression, should not receive smallpox vaccine. Replication of vaccinia virus can be enhanced among people with immunodeficiency diseases and immunosuppression, and result in serious adverse reactions. Also, because the recent vaccination site contains live virus that can be transmitted to other individuals, people with household contacts who are immunosuppressed should also not be vaccinated in nonemergency situations.
Significant immunosuppression can be caused by many diseases, including leukemia, lymphoma, generalized malignancy; solid organ or stem cell transplantation; and humoral or cellular immunity disorders, including HIV infection.
Drugs that can cause immunosuppression include alkylating agents, antimetabolites, radiation, or high-dose corticosteroid therapy. Prednisone doses of 2 milligrams per kilogram of body weight per day or higher or 20 milligrams per day or higher for 14 days or more should be considered immuno suppressive. As with other live vaccines, those on high levels of these drugs should not be immunized for three months after their last dose.
Live viral vaccines are contraindicated during pregnancy. Smallpox vaccine should not be administered to pregnant women or people with pregnant household contacts for nonemergency indications. Pregnancy should also be avoided for at least a month after vaccination. Women who are breastfeeding should not be vaccinated, because the close contact that occurs during this activity could increase the chance of transmission of the vaccine virus to the breastfeeding infant.
Because of the increased risk for eczema vaccinatum, smallpox vaccine should not be administered to people with eczema or atopic dermatitis or a past history of these conditions. People who have a HOUSEHOLD CONTACT with eczema or atopic dermatitis or a history of these conditions should also not be vaccinated.
People with other types of acute, chronic, or exfoliative skin conditions, such as psoriasis, contact dermatitis, or varicella zoster might be at higher risk for disseminated skin rashes from the vaccine, although these rashes are generally not as severe as eczema vaccinatum. People with exfoliative skin conditions should not be vaccinated until the condition is under good control or resolves.
Children less than 12 months of age should not be vaccinated. All vaccinated people should take precautions to prevent virus transmission to young children and other household contacts. As with all vaccines, vaccination should be deferred for people with moderate or severe acute illnesses.
One reminder: in the event of an actual exposure to smallpox, vaccination may be considered for individuals who otherwise have contraindications, because the benefits of vaccination would most likely outweigh the risks.
In summary, smallpox vaccine should not be administered to persons known to have a serious allergy to a prior dose of vaccine or vaccine component; persons with significant immunosuppression from any cause; someone with an immunosuppressed household contact; a woman who is pregnant or attempting to become pregnant, or someone with a household contact who is pregnant; and women who are breastfeeding.
Smallpox vaccine should not be administered to persons with a diagnosis of eczema or atopic dermatitis, including eczema or atopic dermatitis that is not currently active; or a person who has a household contact who has eczema or atopic dermatitis or a history of these diseases; persons with other extensive exfoliative skin conditions; children less than 12 months of age; and persons with a moderate or severe acute illness.
A careful medical history for contraindications to vaccination should be done for EVERY person prior to vaccination. Additional information about contraindications and precautions for smallpox vaccine can also be found on the CDC websites.
- Page last updated December 13, 2002
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