Vaccinia vaccines

R. Ellis, "The AppHcation of rDNA Technology to Vacciues," ia S. A. Plotkin and B. Eantiui, eds.. Vaccinia, Vaccination and Vaccinology, Elsevier, Paris, 1996. 

The last known naturally occurring case of smallpox occurred in Somalia in 1977. In May 1980, the World Health Assembly certified that the world was free of naturally occurring smallpox. By the 1960s, because of vaccination programs and quarantine regulations, the risk for importation of smallpox into the United States had been reduced. As a result, recommendations for routine smallpox vaccination were rescinded in 1971. In 1976, the recommendation for routine smallpox vaccination of health-care workers was also discontinued. In 1982, the only active licensed producer of vaccinia vaccine in the United States discontinued production for general use, and in 1983, distribution to the civilian population was discontinued. All military personnel continued to be vaccinated, but that practice ceased in 1990. Since January 1982, smallpox vaccination has not been required for international travelers, and International Certificates of Vaccination forms no longer include a space to record smallpox vaccination. 

Yes. Vaccinia vaccine is recommended for laboratory workers who directly handle cultures, animals contaminated or infected with, nonhighly attenuated vaccinia virus, recombinant vaccinia viruses derived from nonhighly attenuated vaccinia strains, or other orthopoxviruses that infect humans. These would include monkeypox, cowpox, vaccinia, and variola. Other health-care workers, such as physicians and nurses whose contact with nonhighly attenuated vaccinia viruses is limited to contaminated materials such as medical dressings but who adhere to appropriate infection control measures, are at lower risk for accidental infection than laboratory workers. However, because a theoretical risk for infection exists, vaccination can be offered to this group. Vaccination is not recommended for people who do not directly handle nonhighly attenuated virus cultures or materials or who do not work with animals contaminated or infected with these viruses. 

Treatment — Vaccinia immune globulin must be used in conjunction with a vaccinia vaccine if exposure to a smallpox case occurred more than 4 days earlier. However, only the vaccinia vaccine is required less than 4 days after such contact. The vaccine starts to be protective in approximately 7 days. This vaccine does not provide life-long immunity. Revaccination is recommended at 5- to 10-year intervals. Certain antiviral drugs such as Cidofovir have demonstrated that they confer some protection against infection. Unfortunately, because smallpox has been eradicated, limited research on such drugs has been conducted.3... 

Inhalation, contact with skin lesions or Incubation period 10-14 days Vaccinia immune globulin, vaccinia vaccine... 

Vaccinia Vaccinia immune globulin Consult the CDC.3 Treatment of severe reactions to vaccinia vaccination, including eczema vaccinatum, vaccinia necrosum, and ocular vaccinia. Available from the CDC.3... 

In 1980, the US Public Health Service first recommended the use of Vaccinia (smallpox) vaccine to protect laboratory workers occupationally exposed to orthopoxviruses. In 1991, the Centers for Disease Control, Atlanta, Georgia, published recommendations on Vaccinia vaccine. From 1983 to 1991, 4649 doses of smallpox vaccine were administered, of which 57% were given in 1989-91. The proportion of primary vaccinations increased from 4% in 1983-88 to 14% in 1989-91. Of vaccinees 93% reported no signs or symptoms after vaccination. Reported adverse reactions were mild lymphadenopathy, fever or chills, and tenderness at the site of vaccination. No severe adverse effects were reported. However, one vaccinee reported a spontaneous abortion 5 months after primary vaccination (16). 

Baxby D, Gaskell RM, Gaskell CJ, Bennett M. Ecology of orthopoxviruses and use of recombinant vaccinia vaccines. Lancet 1986 2(8511) 850-1. 

Thorne, CD, Hirshon, JM, Himes, CD, McDiarmid, MA. Emergency Medicine Tools to Manage Smallpox (Vaccinia) Vaccination Comphcations Clinical Practice Guideline and Policies and Procedures. Annals of Emergency Medicine, 42(5) 665-681, 2003... 

A recent program to protect healthcare workers from a possible bioterrorist attack with smallpox reported cases of myocarditis and pericarditis following vaccination (MMWR, 2003), and other studies provided evidence that these effects might be associated causally with vaccinia vaccination (Feery, 1977 Halsell et al., 2003) and may have caused the death of one vaccine recipient (Finlay-Jones, 1964). 

One of the most thorough surveys of adverse reactions associated with vaccinia vaccines was conducted in the United States and published by the CDC in 1968,89 and is summarized in Table 27-3. As a consequence of percutaneous inoculation, infectious vaccine virus is present in the local lesion. Consequently, inadvertent inoculation to other skin and mucous membrane sites (autoinoculation) or to other persons (secondary inoculation) is the most frequent complication of vaccinia intradermal vaccination.90 92 Ocular vaccinia is a particularly troublesome problem resulting from secondary inoculation (Figure 27-6). Erythematous or urticarial rashes may occur approximately 10 days after primary vaccination and, rarely, Stevens-Johnson syndrome occurs. Generalized vaccinia is characterized... 

RATES OF REPORTED COMPLICATIONS ASSOCIATED WITH VACCINIA VACCINATIONS... 

More severe complications of vaccinia vaccination include eczema vaccinatum, progressive vaccinia, and postvaccinial encephalitis. These complications are rare, but occur at least 10 times more often among primary vaccinees than among revaccinees. Eczema vaccinatum is a localized or systemic dissemination of vaccinia virus among persons who have eczema (Figure 27-7). Although usually mild and self-limited, this complication could be severe or even fatal in up to 10% of cases. 

The remaining vaccinia vaccine licensed in the United States (Dryvax, manufactured by Wyeth, Philadelphia, Pa.) is a live, infectious virus prepared from calf lymph. Like all smallpox vaccines that were marketed in the United States, it derived from the NYCBOH strain and contains 108 plaque-forming units per milliliter. Current vaccinia vaccine stocks (> 12 million doses) are held by the CDC. It must be noted that the potency of several lots of this lyophilized vaccine has fallen. Pharmaceutical companies in the United States lack interest in manufacturing new lots of vaccine, owing to the absence of a profitable retail market, antiquation of calf-lymph production techniques and facilities, and the manufacturer s legal liability for vaccination complications. 

Because of the declining potency of the existing smallpox vaccines and continued concerns about the prospect of the use of variola virus in biological warfare, a new vaccinia vaccine is in clinical testing by the U.S. Army Medical Research and Materiel Command, Fort Detrick, Frederick, Maryland. This vaccine was derived from a NYCBOH strain of vaccinia and then produced in human diploid lung fibroblast cell cultures. Unlike calf-lymph vaccines, this cell culture-derived vaccinia vaccine contains no adventitious agents. 

Vaccinia vaccine remains the preeminent countermeasure for preexposure prophylaxis against smallpox. Vaccinia vaccination, vaccinia immune globulin, and methisazone each possess some efficacy in postexposure prophylaxis. 

Individuals who were vaccinated during the WHO smallpox eradication campaign in the 1970s were considered to have immunity to smallpox for at least 3 years, but protection diminishes over time. The only vaccine still available in the United States is a live vaccinia virus manufactured by Wyeth-Ayerst Laboratories (now Wyeth-Lederle Vaccines and Pediatrics, and no longer manufacturing the vaccinia vaccine). The CDC... 

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