Smallpox Vaccination Complications and Care

Centers for Disease Control and Prevention (CDC) issued a report on possible complications from pre-outbreak smallpox vaccinations and reporting adverse events. Because of the unknown prevalence of risks among the population, predictions of adverse reaction rates are not made. Based on cases in the 1960's and recent product testing, most events are minor, but less-frequent serious adverse reactions require prompt evaluation and management.
Pre-outbreak vaccination is contraindicated for those who have the following conditions or have a close contact with: 1) history of atopic dermatitis (eczema), irrespective of severity or activity; 2) active acute, chronic, or exfoliative skin conditions (e.g., severe acne, psoriasis); 3) pregnancy or anticipating pregnancy within 28 days; 4) immunocompromised (e.g., acquired immunodeficiency syndrome, autoimmune conditions, cancer, radiation treatment, immunosuppressive medications); or 5) history of Darier disease (or household contact with active disease). Other contraindications that apply only to vaccination candidates, not their close contacts, are: vaccine-component allergies, breastfeeding, using topical steroid eye medications, current moderate-to-severe illness, and persons aged <18 years.
Vaccinia can be spread from an unhealed site to other persons by close contact and can lead to the same adverse events as in the vaccinee. To avoid transmission of vaccinia virus (found in the vaccine), vaccinees should wash their hands with warm soapy water or hand rubs containing >60% alcohol immediately after they touch their vaccination site or change the bandage. Used bandages should be placed in sealed plastic bags and can be disposed in household trash.
Smallpox vaccine adverse reactions are diagnosed on the basis of examination and history, and some are managed by supportive care. Typically, self-limited reactions include fever, headache, fatigue, myalgia, chills, local skin reactions, nonspecific rashes, erythema multiforme, lymphadenopathy, and pain at the vaccination site. Other reactions are most often diagnosed through a thorough history and exam; they might require specific treatment (e.g., Vaccinia Immune Globulin, a first-line therapy and cidofovir, a second-line therapy, under CDC protocols). Adverse reactions warranting evaluation for therapy include inadvertent inoculation, generalized vaccinia (GV), eczema vaccinatum (EV), progressive vaccinia (PV), postvaccinial central nervous system disease, and fetal vaccinia.
Inadvertent inoculation occurs when vaccinia virus is transferred from a vaccination site to a second location on the vaccinee or to a close contact. Usually, this condition is self-limited and no additional care is needed. Affected eye/eyelid require evaluation by an ophthalmologist and might require topical therapy.
(Cono J et al. MMWR 2003;52(RR04):1-28.)

Comment: This is an extensive clinician's reference on adverse reactions available at www. cdc.gov/mmwr. School nurses may fill many roles with respect to smallpox vaccinations; minimally they should be well informed as the primary information resource for a school community. In the event of an outbreak, CDC will issue outbreak-specific guidance regarding groups to be vaccinated and contraindications. -J.O.