You've probably heard about smallpox in the news over the
past few years. You might be wondering what it is and whether you
should worry about it. There can be a lot of hype about this
disease, so it helps to learn the facts.
Smallpox is an infection caused by the
variola
virus. For centuries, epidemics of smallpox affected people all
over the globe, and the disease was often serious. But in 1796, an
English doctor named Edward Jenner discovered a way to protect
people from getting smallpox, and his experiments eventually led to
the development of the first smallpox vaccine.
The smallpox vaccine worked so well that there hasn't been a
case of smallpox in the United States since 1949. The United States
stopped vaccinating the general population against smallpox in 1972
because the disease was no longer a threat. The world's last
known case of smallpox was reported in Africa in 1977. In 1980, the
World Health Organization (WHO) announced that smallpox was wiped
out - the first (and only) time in history that an infectious
disease was declared eliminated from the planet.
Why Are People Worried About Smallpox?
Although smallpox infection was wiped out many years ago,
samples of the variola virus that causes smallpox were saved in
laboratories. Some people have expressed concern that
terrorists may try to get access to these stored virus samples with
the aim of spreading smallpox infection.
Despite talk about the possibility of terrorists spreading
smallpox as a biological weapon, the reality is that this probably
wouldn't happen for a couple of reasons. First, terrorists
would need access to the virus samples, and the few research
laboratories that keep them have security measures to guard them.
Also, it would be extremely difficult for a group to take the time
to produce a large amount of the variola virus without being
detected.
The smallpox vaccine also would prevent the spread of
disease because it can:
- prevent people from becoming infected if they're
vaccinated quickly after exposure to the virus
- make the illness less severe in people who do
become infected if they're vaccinated within a few
days
After the September 11, 2001, terrorist attacks and the anthrax
scare that same year, the U.S. government took the precaution of
asking several companies to begin making smallpox vaccine again.
Today, there's enough vaccine on hand to protect the American
people in the event of a smallpox outbreak.
Public health officials have a rapid response plan ready to
vaccinate anyone exposed to the disease, as well as people who come
into contact with them. So although a person doesn't need to
get vaccinated at the moment, the vaccine is there in case it's
needed.
Given that the vaccine can stop the spread of the disease,
experts believe it's unlikely that terrorists will go to the
trouble of producing and using smallpox as a biological weapon - it
would take too long and have little effect.
What Happens When Someone Has a Smallpox Infection?
If a person becomes infected with smallpox, it may take anywhere
from 7 to 17 days for symptoms to develop. At first a person may
have flu-like symptoms such as high fever, fatigue, headaches, and
backaches.
Within 2 to 3 days after symptoms start, a rash develops that
typically affects the face, legs, and arms. It starts with red
marks that become filled with pus and crust over. Scabs develop and
then fall off after about 3 to 4 weeks.
Smallpox is very contagious, particularly during the first week
a person has the rash. It is most commonly spread in infected drops
of saliva when people cough or sneeze. Someone is contagious until
after all the scabs have fallen off.
What Works Against Smallpox?
Antibiotics don't work against viruses - they're only
effective against bacteria - so taking them won't help someone
with smallpox. Vaccination is the only effective weapon against the
spread of smallpox. Immunization successfully wiped out
smallpox before and, should it become necessary, can help stop any
future outbreaks. Researchers are also working to develop other
treatments, too.
It's very unlikely that you will ever be exposed to the
virus that causes smallpox. But if you're worried about
it, talk to a science teacher or medical professional, who can help
you find the answers to any questions you may have about
smallpox.
Reviewed by:
Elana Pearl Ben-Joseph, MD
Date reviewed: September 2006
Note: All information is for educational purposes only. For specific medical advice,
diagnoses, and treatment, consult your doctor.
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