1. What is the
risk of developing smallpox?
Smallpox does not
exist as a naturally occurring disease anywhere in
the world. The only risk of smallpox would
come from the use of smallpox as a weapon of
bioterrorism. Government security experts
believe that bioterrorists in several countries may
have smallpox. No one knows for certain whether or
not they have smallpox or if smallpox will be used
as a weapon. Most infectious disease experts
believe that the risk of any individual being
exposed to smallpox is extremely low.
2. How good is this
No vaccine is
perfect. The smallpox vaccine provides approximately
95 percent protection against smallpox. This is
about as effective as most other live viral
3. What kinds of
adverse reactions can occur?
causes a local infection on the arm. A small group
of blisters or vesicles develop associated with
inflammation, swelling and tenderness that lasts for
one to two weeks. About 10 percent of people develop
an exaggerated reaction with more marked swelling,
redness and tenderness and decreased use of the arm
for a few days. Some people develop red
streaks going around the arm, which resolve
spontaneously, but this reaction is sometimes
mistakenly assumed to be a secondary bacterial
infection. Headache, fever, and feeling poorly
for a few days occur frequently. About
one-third of healthy young adults who were
vaccinated reported missing at least one day of
work, school, or participating in usual activities.
More serious reactions occur much less commonly.
The vaccine virus
can be transmitted from the vaccination site to some
other part of the body or to people who have direct
contact with a vaccinated person. The virus is
transmitted on hands after touching the vaccine
site. There is no evidence that the virus is
transmitted through respiratory droplets or that
there is any risk from being in the same room as a
vaccinated person. If the vaccine virus is put on an
area where the skin is broken or on a mucous
membrane such as the mouth, eye, vagina, or rectum,
then sores develop that are similar to the sore at
the vaccination site. This can create serious
problems if the viruses are placed in or around the
eye or the genital area. The vaccine is not
recommended for anybody with acute or chronic skin
conditions that could predispose to this problem.
People with eczema are at particularly high risk of
developing severe reactions. Any person with eczema,
atopic dermatitis, or any household member who has
these conditions should not be vaccinated.
When the smallpox
vaccine was given to pregnant women, the vaccine
virus was sometimes transmitted to their unborn
babies and caused serious infections and sometimes
premature birth. When the vaccine was given to
children under a year of age, they had a higher risk
of developing encephalitis than older children and
adults. The risk in adults is about one to two
per million and this complication can lead to
long-term brain damage or death.
4. Are there
special risks for patients with immune disorders?
Yes, patients with
immune deficiency disorders and their household
contacts should not be vaccinated. Persons
with defects in lymphocyte function, including
people with leukemia and other forms of cancer, are
at high risk of developing a serious and frequently
fatal complication called progressive vaccinia.
Although patients with mild defects in the immune
system that do not affect lymphocyte function may
not be at increased risk, there is no reason for
these people to be vaccinated at this time. If there
were to be outbreaks of smallpox associated with
bioterrorism, these people should check with their
doctors before considering smallpox vaccination.
5. I am being
treated with prednisone. Should I take the vaccine?
Any person with a
condition that requires the use of prednisone or
other immunosuppressive agents should not receive
the smallpox vaccine at this time. Although
low doses of prednisone do not usually cause any
problems with live viral vaccines, these persons
might require higher doses of prednisone if their
underlying condition became more severe. We do
not have any data on what doses of prednisone might
be safe for people who receive the smallpox vaccine.
6. If I have an
autoimmune disease, should members of my family take the
If you have an
autoimmune disease that might require the use of
steroids or other therapy that could affect the
immune system, no one in your family who lives in
the same household should receive smallpox vaccine
because you might acquire the smallpox vaccine virus
from your family member.
7. If I have an
autoimmune disease, should I stay away from my place of
employment if there are people there who have been
vaccinated? If so, how long should I stay away?
You do not need to
stay away from your place of work where people have
received the smallpox vaccine. We do not have the
same physical contact with people in the workplace
that we have with family members. Vaccinated
individuals in the workplace should have their
smallpox vaccine site covered with special bandages
that will markedly reduce, if not eliminate, the
risk of their transmitting the virus to you.
If vaccinated people take appropriate precautions
with regard to care of the vaccine site, then they
can continue to shake hands and have other minimal
contact with other persons.
8. Are there any special precautions that I as an
autoimmune disease patient should take if there is a
national vaccination program?
If your disorder
puts you at increased risk, you should take care to
minimize direct touching contact with people who may
have received the smallpox vaccine and who have an
open sore that could contain the virus. If your job
requires direct physical contact with people, such
as people who do massage therapy, then you might
consider asking clients who have been vaccinated not
to come for therapy during the time when they have
an open sore from the vaccine.
9. If I have an
autoimmune disease that affects the skin, should I take
If you have active
lesions from psoriasis, cutaneous vasculitis,
bullous pemphigoid, BehHets
disease, discoid lupus, Moorens ulcer, or any other
skin disorder, you should not receive the vaccine.
If your skin disorder is under control, you do not
have any open lesions, and the vaccine is highly
recommended for you because of your occupation, then
you might consider receiving the vaccine after
consultation with your physician. If it is not
essential for you to be immunized, then we would
advise against it.
10. Is there any
way of treating the adverse reactions if they occur?
reactions can be treated with a special immune
globulin preparation that appears to help patients
with eczema vaccinatum, severe inoculation around
the eye or other sites, and possibly for progressive
vaccinia. There is one antiviral drug that is
available for investigational purposes, but it has a
high rate of serious side effects. These drugs are
available through the Centers for Disease Control
11. Is there a safer vaccine available for patients
with autoimmune disease?
A new smallpox
vaccine is currently being tested and should become
available sometime during 2003. This vaccine
is made from the same virus that is in the current
smallpox vaccine. The new vaccine will be
grown in cell culture rather than on the calf skin.
Since the viruses are the same, the new vaccine will
probably have the same risk of adverse reactions as
the current vaccine. Scientists are working on
developing safer vaccines against smallpox, but it
will take at least five to ten years before these
vaccines might become available.
12. Is the situation likely to change with regard to
the risk of exposure to smallpox?
infectious disease experts recommend against routine
vaccination of the civilian population because the
risks of exposure to smallpox are very small and
probably close to zero. Experts are constantly
reevaluating the potential for exposure from
bioterrorism. As the United Nations
investigations in Iraq continue, we should learn
whether or not this country has produced smallpox
for possible use as a weapon. If there was one small
event in a single location, this may not change the
equation with regard to balancing the risks and
benefits from this vaccine for the general
population. Experts would contact everyone who had
been exposed to be sure that they were immunized,
but it would not require immunization of the general
can protect against smallpox even when its
administered up to four days after exposure.
If someone has a known exposure to smallpox, then
there are very few contraindications to using the
vaccine and people with skin disorders and mild
immune deficiency disorders would be immunized. If
there was a confirmed large outbreak in your local
community, then many experts believe that almost
everyone in that community should receive the
vaccine. We must always weigh the potential benefits
of vaccines against the potential risks. At
this time smallpox vaccination is not warranted for
the general public.