WARNINGS
Included as part of the PRECAUTIONS section.
PRECAUTIONS
Persons at greatest risk of experiencing serious
vaccination complications are often those at greatest risk for death from
smallpox. The risk for experiencing serious vaccination complications must be
weighed against the risks for experiencing a potentially fatal smallpox
infection.
Serious Complications And Death
Serious complications that may
follow either primary live vaccinia smallpox vaccination or revaccination
include: myocarditis and/or pericarditis, encephalitis, encephalomyelitis,
encephalopathy, progressive vaccinia (vaccinia necrosum), generalized vaccinia,
severe vaccinial skin infections, erythema multiforme major (including
Stevens-Johnson syndrome), eczema vaccinatum, blindness, and fetal death in
pregnant women. These complications may rarely lead to severe disability,
permanent neurological sequelea and death. Based on clinical trials, symptoms
of suspected myocarditis or pericarditis (such as chest pain, raised troponin/cardiac
enzymes, or ECG abnormalities) occur in 5.7 per 1000 primary vaccinations. This
finding includes cases of acute symptomatic or asymptomatic myocarditis or
pericarditits or both. Historically, death following vaccination with live
vaccinia virus is a rare event; approximately 1 death per million primary
vaccinations and 1 death per 4 million revaccinations have occurred after
vaccination with live vaccinia virus. Death is most often the result of sudden
cardiac death, postvaccinial encephalitis, progressive vaccinia, or eczema
vaccinatum. Death has also been reported in unvaccinated contacts accidentally
infected by individuals who have been vaccinated.
Incidence Of Serious Complications In 1968 US
Surveillance Studies
Estimates of the risks of occurrence of serious
complications after primary vaccination and revaccination, based on safety
surveillance studies conducted when live vaccinia virus smallpox vaccine (i.e.,
New York City Board of Health strain, Dryvax®) was routinely recommended, are
as follows:
Table 1A : Rates of reported complicationsa
associated with primary vaccinia vaccinations (cases/million vaccinations)b
Age (yrs) |
< 1 |
1-4 |
5-19 |
≥ 20 |
Overall ratesh |
Inadvertent inoculationc § |
507.0 |
577.3 |
371.2 |
606.1 |
529.2 |
Generalized vaccinia |
394.4 |
233.4 |
139.7 |
212.1 |
241.5 |
Eczema vaccinatum |
14.1 |
44.2 |
34.9 |
30.3 |
38.5 |
Progressive vacciniad |
--g |
3.2 |
--g |
--g |
1.5 |
Post-vaccinial encephalitis |
42.3 |
9.5 |
8.7 |
--g |
12.3 |
Deathe |
5 |
0.5 |
0.5 |
unknown |
-- |
Totalf |
1549.3 |
1261.8 |
855.9 |
1515.2 |
1253.8 |
a See article for descriptions of
complications.
b Adapted from Lane JM, Ruber FL, Neff JM, Millar JD. Complications
of smallpox vaccination, 1968: results of ten statewide surveys. J Infect Dis.
1970; 122:303-309.
c Referenced as accidental implantation.
d Referenced as vaccinia necrosum.
e Death from all complications.
f Rates of overall complications by age group include complications
not provided in this table, including severe local reactions, bacterial
superinfection of the vaccination site, and erythema multiforme.
g No instances of this complication were identified during the 1968
10-state survey.
h Overall rates for each complication include persons of unknown
age. |
Table 1B : Rates of reported serious complicationsa
associated with vaccinia revaccinations (cases/million vaccinations)b
Age (yrs) |
< 1 |
1-4 |
5- 19 |
≥ 20 |
Overall ratesb |
Inadvertent inoculationc |
g |
109.1 |
47.7 |
25.0 |
42.1 |
Generalized vaccinia |
g |
g |
9.9 |
9.1 |
9.0 |
Eczema vaccinatum |
g |
g |
2.0 |
4.5 |
3.0 |
Progressive vacciniad |
g |
g |
g |
6.8 |
3.0 |
Post-vaccinial encephalitis |
g |
g |
g |
4.5 |
2.0 |
Deathe |
-- |
-- |
-- |
-- |
-- |
Totalf |
g |
200.0 |
85.5 |
113.6 |
108.2 |
See Table 1A for explanation of footnotes. |
Incidence Of Serious Complications And Emergence Of Myocarditis
And/Or Pericarditis In 2002-2005
Data on the incidence of adverse events among U.S.
military personnel and civilian first responders vaccinated with Dryvax®, a
licensed live vaccinia virus smallpox vaccine, during vaccination programs
initiated in December 2002 are shown below in Table 2. The incidence of
preventable adverse events (eczema vaccinatum, contact transmission, and
auto-inoculation) were notably lower in these programs when compared with data
collected in the 1960s; presumably because of better vaccination screening
procedures and routine use of protective bandages over the inoculation site.
Myocarditis and pericarditis were not commonly reported following smallpox
vaccination in the 1960s, but emerged as a more frequent event based on more
active surveillance in the military and civilian programs.
Table 2 : Serious adverse events in 2002-20055
Adverse event |
Department of Defense program (n=730,580a) as of Jan05 |
Department of Health and Human Services program (n=40, 422) as of Jan04b |
N |
Incidence/ million |
N |
Incidence /million |
Myo/pericarditis Post-vaccinal |
86 |
117.71 |
21 |
519.52 |
encephalitis |
1 |
1.37 |
1 |
24.74 |
Eczema vaccinatum |
0 |
0.00 |
0 |
0.00 |
Generalized vaccinia |
43 |
58.86 |
3 |
74.22 |
Progressive vaccinia |
0 |
0.00 |
0 |
0.00 |
Fetal vaccinia |
0 |
0.00 |
0 |
0.00 |
Contact transmission |
52 |
71.18 |
0 |
0.00 |
Auto-inoculation (nonocular) |
62 |
84.86 |
20 |
494.78 |
Ocular vaccinia |
16 |
21.90 |
3 |
74.22 |
a 71% primary vaccination; 89% male; median
age 28.5 yr
b 36% primary vaccination; 36% male; median age 47.1 yr |
Myocarditis And Pericarditis In The ACAM2000 Clinical
Trial Experience
In clinical trials involving 2983 subjects who received
ACAM2000 and 868 subjects who received Dryvax®, ten (10) cases of suspected
myocarditis [0.2% (7 of 2983) ACAM2000 subjects and 0.3% (3 of 868) Dryvax® subjects]
were identified. The mean time to onset of suspected myocarditis and/or
pericarditis from vaccination was 11 days, with a range of 9 to 20 days. All
subjects who experienced these cardiac events were naïve to vaccinia. Of the 10
subjects, 2 were hospitalized. None of the remaining 8 cases required
hospitalization or treatment with medication. Of the 10 cases, 8 were
sub-clinical and were detected only by ECG abnormalities with or without
associated elevations of cardiac troponin I. All cases resolved by 9 months,
with the exception of one female subject in the Dryvax® group, who had
persistent borderline abnormal left ventricular ejection fraction on
echocardiogram. The best estimate of risk for myocarditis and pericarditis is
derived from the Phase 3 ACAM2000 clinical trials where there was active
monitoring for potential of myocarditis and pericarditis. Among vaccinees naïve
to vaccinia, 8 cases of suspected myocarditis and pericarditis were identified
across both treatment groups, for a total incidence rate of 6.9 per 1000
vaccinees (8 of 1,162). The rate for the ACAM2000 treatment group were similar:
5.7 (95% CI: 1.9-13.3) per 1000 vaccinees (5 of 873 vaccinees) and for the
Dryvax® group 10.4 (95% CI: 2.1-30.0) per 1000 vaccinees (3 of 289 vaccinees).
No cases of myocarditis and/or pericarditis were identified in 1819 previously
vaccinated subjects. The long-term outcome of myocarditis and pericarditis
following ACAM2000 vaccination is currently unknown.
Cardiac Disease
Ischemic cardiac events, including fatalities, have been
reported following smallpox vaccination; the relationship of these events, if
any, to vaccination has not been established. In addition, cases of
non-ischemic, dilated cardiomyopathy have been reported following smallpox
vaccination; the relationship of these cases to smallpox vaccination is
unknown.
There may be increased risks of adverse events with
ACAM2000 in persons with known cardiac disease, including those diagnosed with
previous myocardial infarction, angina, congestive heart failure,
cardiomyopathy, chest pain or shortness of breath with activity, stroke or
transient ischemic attack, or other heart conditions. In addition, subjects who
have been diagnosed with 3 or more of the following risk factors for ischemic
coronary disease: 1) high blood pressure; 2) elevated blood cholesterol; 3)
diabetes mellitus or high blood sugar; 4) first degree relative (for example
mother, father, brother, or sister) who had a heart condition before the age of
50; or 5) smoke cigarettes may have increased risks.
Ocular Complications And Blindness
Accidental infection of the eye (ocular vaccinia) may
result in ocular complications including keratitis, corneal scarring and
blindness. Patients who are using corticosteroid eye drops may be at increased
risk of ocular complications with ACAM2000.
Presence Of Congenital Or Acquired Immune Deficiency
Disorders
Severe localized or systemic infection with vaccinia
(progressive vaccinia) may occur in persons with weakened immune systems,
including patients with leukemia, lymphoma, organ transplantation, generalized
malignancy, HIV/AIDS, cellular or humoral immune deficiency, radiation therapy,
or treatment with antimetabolites, alkylating agents, or high-dose
corticosteroids ( > 10 mg prednisone/day or equivalent for ≥ 2 weeks).
The vaccine is contraindicated in individuals with severe immunodeficiency [See
CONTRAINDICATIONS]. Vaccinees with close contacts who have these
conditions may be at increased risk because live vaccinia virus can be shed and
be transmitted to close contacts.
History Or Presence Of Eczema And Other Skin Conditions
Persons with eczema of any description such as, atopic
dermatitis, neurodermatitis, and other eczematous conditions, regardless of
severity of the condition, or persons who have a history of these conditions at
any time in the past, are at higher risk of developing eczema vaccinatum.
Vaccinees with close contacts who have eczematous conditions, may be at
increased risk because live vaccinia virus can shed and be transmitted to these
close contacts. Vaccinees with other active acute, chronic or exfoliative skin
disorders (including burns, impetigo, varicella zoster, acne vulgaris with open
lesions, Darier's disease, psoriasis, seborrheic dermatitis, erythroderma,
pustular dermatitis, etc.), or vaccinees with household contacts having such
skin disorders might also be at higher risk for eczema vaccinatum.
Infants ( < 12 Months Of Age) And Children
ACAM2000 has not been studied in infants or children. The
risk of serious adverse events following vaccination with live vaccinia virus
is higher in infants. Vaccinated persons who have close contact with infants,
e.g., breastfeeding, must take precautions to avoid inadvertent transmission of
ACAM2000 live vaccinia virus to infants.
Pregnancy
ACAM2000 has not been studied in pregnant women. Live
vaccinia virus vaccines can cause fetal vaccinia and fetal death. If ACAM2000
is administered during pregnancy, the vaccinee should be apprised of the
potential hazard to the fetus [See Use in Specific Populations].
Vaccinees with close contacts who are pregnant may be at increased risk because
live vaccinia virus can shed and be transmitted to close contacts.
Allergy To ACAM2000 Smallpox Vaccine Or Its Components
ACAM2000 contains neomycin and polymyxin B. Persons
allergic to these components may be at higher risk for adverse events after
vaccination. Both the vaccine and diluent vial stoppers do not contain latex
material.
Management Of Smallpox Vaccine Complications
The CDC can assist physicians in the diagnosis and
management of patients with suspected complications of vaccinia (smallpox)
vaccination. Vaccinia Immune Globulin (VIG) is indicated for certain
complications of vaccination live vaccinia virus smallpox vaccine. If VIG is
needed or additional information is required, physicians should contact the CDC
at (404) 639-3670, Monday through Friday 8 AM to 4:30 PM Eastern Standard Time;
at other times call (404) 639-2888.
Prevention Of Transmission Of Live Vaccinia Virus
The most important measure to prevent inadvertent
auto-inoculation and contact transmission from vaccinia vaccination is thorough
hand washing after changing the bandage or after any other contact with the
vaccination site.
Individuals susceptible to adverse effects of vaccinia
virus, i.e., those with cardiac disease, eye disease, immunodeficiency states,
including HIV infection, eczema, pregnant women and infants, should be
identified and measures should be taken to avoid contact between those
individuals and persons with active vaccination lesions.
Recently vaccinated healthcare workers should avoid
contact with patients, particularly those with immunodeficiencies, until the
scab has separated from the skin at the vaccination site. However, if continued
contact with patients is unavoidable, vaccinated healthcare workers should
ensure the vaccination site is well covered and follow good hand-washing
technique. In this setting, a more occlusive dressing may be used.
Semipermeable polyurethane dressings are effective barriers to shedding of
vaccinia. However, exudate may accumulate beneath the dressing, and care must
be taken to prevent viral spread when the dressing is changed. In addition,
accumulation of fluid beneath the dressing may increase skin maceration at the
vaccination site. Accumulation of exudate may be decreased by first covering
the vaccination with dry gauze, then applying the dressing over the gauze. The
dressing should be changed every 1-3 days [See Self Inoculation and Spread
to Close Contacts and Care of the Vaccination Site and Potentially
Contaminated Materials].
Blood And Organ Donation
Blood and organ donation should be avoided for at least
30 days following vaccination with ACAM2000.
Limitations Of Vaccine Effectiveness
ACAM2000 smallpox vaccine may not protect all persons
exposed to smallpox.
Patient Counseling Information
Please refer patient to the Medication Guide prepared for
ACAM2000 Smallpox Vaccine.
Serious Complications Of Vaccination
Patients must be informed of the major serious adverse events
associated with vaccination, including myocarditis and/or pericarditis,
progressive vaccinia in immunocompromised persons, eczema vaccinatum in persons
with skin disorders, auto- and accidental inoculation, generalized vaccinia,
urticaria, erythema multiforme major (including Stevens-Johnson syndrome) and
fetal vaccinia in pregnant women.
Protecting Contacts At Highest Risk For Adverse Events
Patients must be informed that they should avoid contact
with individuals at high risk of serious adverse effects of vaccinia virus, for
instance, those with past or present eczema, immunodeficiency states including
HIV infection, pregnancy, or infants less than 12 months of age.
Self-inoculation And Spread To Close Contacts
Patients must be advised that virus is shed from the
cutaneous lesion at the site of inoculation from approximately Day 3 until
scabbing occurs, typically between Days 14-21 after primary vaccination.
Vaccinia virus may be transmitted by direct physical contact. Accidental
infection of skin at sites other than the site of intentional vaccination
(self-inoculation) may occur by trauma or scratching. Contact spread may also
result in accidental inoculation of household members or other close contacts.
The result of accidental infection is a pock lesion(s) at an unwanted site(s)
in the vaccinee or contact, and resembles the vaccination site.
Self-inoculation occurs most often on the face, eyelid, nose, and mouth, but
lesions at any site of traumatic inoculation can occur. Self-inoculation of the
eye may result in ocular vaccinia, a potentially serious complication.
Care Of The Vaccination Site And Potentially Contaminated
Materials
Patients must be given the following instructions:
- The vaccination site must be completely covered with a
semipermeable bandage. Keep site covered until the scab falls off on its own.
- The vaccination site must be kept dry. Normal bathing may
continue, but cover the vaccination site with waterproof bandage when bathing.
The site should not be scrubbed. Cover the vaccination site with loose gauze
bandage after bathing.
- Don't scratch the vaccination site. Don't scratch or pick
at the scab.
- Do not touch the lesion or soiled bandage and
subsequently touch other parts of the body particularly the eyes, anal and
genital areas that are susceptible to accidental (auto-) inoculation.
- After changing the bandage or touching the site, wash
hands thoroughly with soap and water or > 60% alcohol-based hand-rub
solutions.
- To prevent transmission to contacts, physical contact of
objects that have come into contact with the lesion (e.g. soiled bandages,
clothing, fingers) must be avoided.
- Wash separately clothing, towels, bedding or other items
that may have come in direct contact with the vaccination site or drainage from
the site, using hot water with detergent and/or bleach. Wash hands afterwards.
- Soiled and contaminated bandages must be placed in
plastic bags for disposal.
- The vaccinee must wear a shirt with sleeves that covers the
vaccination site as an extra precaution to prevent spread of the vaccinia
virus. This is particularly important in situations of close physical contact.
- The vaccinee must change the bandage every 1 to 3 days.
This will keep skin at the vaccination site intact and minimize softening.
- Don't put salves or ointments on the vaccination site.
- When the scab fall off, throw it away in a sealed plastic
bag and wash hands afterwards.
Use In Specific Populations
Pregnancy
Pregnancy Category D
ACAM2000 has not been studied in pregnant women. Live
vaccinia virus vaccines can cause fetal harm when administered to a pregnant
woman. Congenital infection, principally occurring during the first trimester,
has been observed after vaccination with live vaccinia smallpox vaccines, although
the risk may be low. Generalized vaccinia of the fetus, early delivery of a
stillborn infant, or a high risk of perinatal death has been reported.
The only setting in which vaccination of pregnant women
should be considered is when exposure to smallpox is considered likely. If this
vaccine is used during pregnancy, or if the vaccinee lives in the same
household with or has close contact with a pregnant women, the vaccinee should
be apprised of the potential hazard to the fetus. Healthcare providers, state
health departments, and other public health staff should report to the National
Smallpox Vaccine in Pregnancy Registry all cases in which persons who received
ACAM2000, or were exposed to a woman who received ACAM2000 within 28 days after
vaccination, during pregnancy, or within 42 days prior to conception. Civilian
women should contact their healthcare provider or state health department for
help enrolling in the registry. Clinicians or public health staff should report
civilian cases through their state health department or to CDC, telephone
404-639-8253 or 877 554 4625. Military cases should be reported to the DoD,
telephone 619 553-9255, Defense Switched Network (DSN) 553-9255, fax 619
767-4806 or e-mail [email protected]
Nursing Mothers
ACAM2000 has not been studied in lactating women. It is
not known whether vaccine virus or antibodies are secreted in human milk. Live
vaccinia virus can be inadvertently transmitted from a lactating mother to her
infant. Infants are at high risk of developing serious complications from live
vaccinia smallpox vaccination.
Pediatric Use
The safety and effectiveness of ACAM2000 have not been
established in the age groups from birth to age 16. The use of ACAM2000 in all
pediatric age groups is supported by evidence from the adequate and
well-controlled studies of ACAM2000 in adults and with additional historical
data with use of live vaccinia virus smallpox vaccine in pediatrics. Before the
eradication of smallpox disease, live vaccinia virus smallpox vaccine was
administered routinely in all pediatric age groups, including neonates and
infants, and was effective in preventing smallpox disease. During that time,
live vaccinia virus was occasionally associated with serious complications in
children, the highest risk being in infants younger than 12 months of age. [See
WARNINGS AND PRECAUTIONS].
Geriatric Use
Clinical studies of ACAM2000 did not include sufficient
numbers of subjects aged 65 and over to determine whether they respond
differently from younger subjects. There are no published data to support the
use of this vaccine in geriatric (persons > 65 years) populations.
5 Poland GA, Grabenstein JD, Neff JM. The US smallpox
vaccination program: a review of a large modern era smallpox vaccination
implementation program. Vaccine. 2005;23:2078-2081.