Smallpox Alert in Jails and Prisons
Smallpox vaccine is made from live vaccinia virus and does not contain variola virus, the causative agent of smallpox. Because vaccinia viral replication and shedding occurs at the vaccination site, unintended transmission can occur from as early as two days after vaccination until the scab separates from the skin two to three weeks later.
Replication of vaccinia virus can be enhanced among immunosuppressed patients. Except in the setting of an outbreak, smallpox vaccination is contraindicated for individuals with atopic dermatitis (eczema) or other skin conditions that disrupt the epidermis; women who are pregnant or who may become pregnant in the 28 days after vaccination; and those immunosuppressed due to HIV infection, autoimmune conditions, malignancy, radiation treatment, medications, or other immunodeficiencies.
Persons with HIV infection might have an increased risk for severe adverse reactions resulting from exposure to live-virus vaccines. Because the HIV epidemic began after routine smallpox vaccination ended in the 1970s, data are limited regarding the risks from vaccination among HIV-infected persons.
On March 25, 2003, the CDC reported that among 25,645 civilians who have been vaccinated, there have been three cases of myocardial infarction, one of which resulted in death; two cases of angina, and two cases of myopericarditis. Based upon this information, the CDC added the recommendation that persons with known cardiac disease such as cardiomyopathy, previous heart attack, angina, or other evidence of coronary artery disease be temporarily deferred from smallpox vaccination.
Vaccinia can be transmitted to others from an unhealed vaccination site. Although nosocomial transmission of vaccinia from either patients or health care workers to patients has been described, transmission usually requires close interaction as would occur in a household or dormitory setting.
Cases arising from transmission through contact with a recently vaccinated person have resulted in either eczema vaccinatum (EV) or inadvertent inoculation (when vaccinia virus is transferred from a vaccination site to a second location on the body or to a close contact), occurring 5-19 days after exposure to the source case. The incidence of contact vaccinia in the 1960s was 2-6/100,000 first-time vaccinations. Since there are many more people living today with severe immunocompromising conditions, this may underestimate the current risk.
The CDC's Advisory Committee on Immunization Practices (ACIP) believes that optimal infection-control practices and appropriate site care should prevent transmission of vaccinia virus. Those providing direct patient care or who are in contact with inmates should keep their vaccination site covered with gauze dressing to absorb exudates; this dressing should be covered with a semipermeable membrane to minimize the risk of transmission. The dressing should also be covered by a layer of clothing until the scab separates, which may take 14-21 days. Dressings used to cover the site should be changed frequently to prevent maceration and accumulation of exudates.
Since transmission occurs through contact with the vaccination site, the most critical measure in preventing contact transmission is consistent hand hygiene with antimicrobial soap and water or an approved alcohol-based hand-rub (one that contains >60% alcohol) after any contact with the vaccination site or contact with materials that have come into contact with the site.
The CDC recommends that hospitals provide a program in which designated staff (available 24 hours a day) assess the dressings of all vaccinated health care workers daily before shifts begin, determine if dressings need changing, and change the dressing as needed. In correctional settings, designated personnel may be responsible for assessing vaccination sites of correctional officers. These designated staff should assess the vaccination site for local reactions and for vaccine take, reinforce education regarding the need for meticulous hand hygiene, and record and report serious adverse events after vaccination. When feasible, staff responsible for dressing changes for teams should be vaccinated, but having non-vaccinated staff change dressings is acceptable. All persons handling bandages should observe contact precautions.
The ACIP recommends that administrative leave is not routinely required for newly vaccinated health care personnel unless they are physically unable to work because of systemic signs and symptoms of illness; have extensive skin lesions that cannot be covered adequately; or are unable to adhere to the recommended infection-control precautions. However, the CDC expects that as many as 30% of the nation's hospitals may opt out of the voluntary immunization program because of concerns about health risks to those being vaccinated and the potential transfer of vaccinia to vulnerable populations. Each correctional system should take these issues into account when making a decision concerning administrative leave or reassignment.
Adverse reactions are usually self-limited and include fever, headache, fatigue, myalgia, chills, local skin reactions, nonspecific rashes, erythema multiforme, lymphadenopathy, and pain at the vaccination site. Adverse reactions that might require further evaluation or treatment include inadvertent inoculation, generalized vaccinia (GV), eczema vaccinatum (EV), progressive vaccinia (PV), postvaccinial central nervous system disease, and fetal vaccinia.
Persons with PV, EV, and severe GV or inadvertent inoculation might benefit from therapy with vaccinia immune globulin (VIG) or cidofovir, available from the CDC under Investigational New Drug protocols.
Inadvertent inoculation is usually self-limited and no additional care is needed. However, inoculations of the eye and eyelid require evaluation by an ophthalmologist and might require therapy with topical antiviral or antibacterial medications, VIG, or topical steroids.
GV is characterized by a disseminated maculopapular or vesicular rash, frequently on an erythematous base, which usually occurs six to nine days after first-time vaccination. This condition is usually self-limited and benign, although treatment with VIG might be required when the patient is systemically ill or found to have an underlying immunocompromising condition.
EV occurs among persons with a history of atopic dermatitis (eczema), and is a localized or generalized papular, vesicular, or pustular rash, which can occur anywhere on the body, with a predilection for areas of previous atopic dermatitis lesions. Patients with EV are often systemically ill and usually require VIG.
PV is a rare, severe, and often fatal complication among persons with immunodeficiencies, characterized by painless progressive necrosis at the vaccination site with or without metastases to distant sites (e.g., skin, bones, and other viscera). This disease carries a high mortality rate, and management of PV should include aggressive therapy with VIG, intensive monitoring, and tertiary-level supportive care.
Central nervous system disease, which includes postvaccinial encephalopathy (PVE) and postvaccinial encephalomyelitis (or encephalitis) (PVEM), can occur after smallpox vaccination. PVE is most common among infants aged <12 months. Although no specific therapy exists for PVE or PVEM, supportive care, anticonvulsants, and intensive care might be required.
Fetal vaccinia, resulting from vaccinial transmission from mother to fetus, is a rare, but serious, complication of smallpox vaccination during pregnancy or shortly before conception. It is manifested by skin lesions and organ involvement, and often results in fetal or neonatal death. It is recommended that pregnancy be avoided until 28 days after vaccination. Pregnant individuals who are considering vaccination (and pregnant spouses of vaccinated personnel) should be made aware of this risk.
Conditions easily confused with vaccinia infection (i.e., varicella, herpes zoster, herpes simplex, and enteroviruses), should be considered first, in particular for someone who has not been vaccinated or had contact with an individual who was vaccinated.
Serologic testing for vaccinia is uninformative because it cannot be used to distinguish vaccinia immunity from vaccinia infection unless baseline antibody titers are available.
Diagnostic tests for vaccinia are available only for research purposes, but are undergoing multicenter validation studies that might enable FDA to approve the test reagents for diagnostic use.
Prophylactic treatment with VIG is not recommended for persons or close contacts with contraindications to smallpox vaccination who are inadvertently inoculated or exposed.
Suspected cases of these illnesses or other severe adverse events after smallpox vaccination should be reported immediately to state health departments and to the Vaccine Adverse Event Reporting System. Reports can be made online at https://secure.vaers.org/VaersDataEntryintro.htm. To request clinical consultation and IND therapies for vaccinia-related adverse reactions for civilians, contact your state health department or the CDC's Clinician Information Line (877-554-4625). Those with suspected adverse events should be removed from work until evaluated and cleared to return.
Suppression of tuberculin skin test (TST) reactivity has been demonstrated after administration of smallpox vaccine. Health care workers scheduled to receive an annual TST should not receive the skin test for one month after smallpox vaccination to prevent possible false-negative reactions.
Joe Bick, M.D. is Director of HIV Treatment Services at California Medical Facility, Vacaville, California Department of Corrections.
* Disclosure: Nothing to disclose.
This article was provided by Brown Medical School. It is a part of the publication HEPP Report.