What is Smallpox

7/28/2019 What is Smallpox

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What Is Smallpox?

You may have heard about smallpox and wondered what it is or whether you or anyone you know

could get it. Some people are worried that the germ that causes smallpox could be spread and

used as a weapon. Although this is a frightening thought, the government and police are working

on ways to protect us.

In the meantime, it's important not to panic over smallpox the chance that you or someone in

your family could ever get it is very small. One of the ways you can feel better is to learn about

the disease. When you know what it is and how you can get it, it doesn't seem quite as scary.

So here are answers to some questions you might have about smallpox:

What is smallpox?Smallpox is a very serious illness caused by a virus called the variola (say: vair-ee-OH-

luh) virus. Smallpox gets its name from the pus-filled blisters (or pocks) that form during

the illness. Although the names may sound alike, smallpox is not related to chickenpox,

which is a milder disease caused by a different virus.

Although people are concerned that the smallpox virus might be used as a weapon, this

would be difficult for anyone to do. Right now, there are no cases of smallpox disease in

the United States. In fact, the last case of smallpox in the United States was in 1949, and

the last case in the world was in 1977. Some samples of the virus that causes the disease

are still kept in laboratories, though.

How is smallpox spread?Smallpox is contagious. That means the virus can spread to others. It spreads through tiny

drops of an infected person's saliva (spit) when the person coughs, talks, or sneezes.

Smallpox usually passes from person to person during close, face-to-face contact.

How is it diagnosed?If someone does get smallpox, a doctor can recognize the disease because it causes a

special kind of rash. The rash shows up as blisters on the skin that fill with fluid and crust

over. This might sound like chickenpox, but the blisters look different from the blisters that

chickenpox causes. The other symptoms of smallpox are like those of many other less

serious illnesses: fever, headache, backache, and feeling tired.

What is the smallpox vaccine?A vaccine (say: vak-SEEN), a type of shot, can prevent infection with the virus that

causes smallpox. Years ago, people were vaccinated against smallpox. Today, smallpox

vaccines aren't given because nobody has had the disease for many years.


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Although you can't and don't need to get a smallpox vaccine right now, there is a

supply of the vaccine in case there's an outbreak of the disease. Scientists also are

working to make more vaccine to have on hand for the future.

Are there medicines to take for smallpox?There are no pills that can treat smallpox, but scientists are doing research to try to

develop medicine for the disease. If someone does become infected with the smallpox

virus, getting the vaccine within a few days of becoming infected can lessen the disease's

symptoms.

If you still feel scared when you hear about smallpox, remember that it's very unlikely that you,

your family, or anyone you know will ever come in contact with the virus that causes it. Talking to

your teacher or parent may make you feel better and give you answers to any other questions you

may have.

What is smallpox?

Smallpox is an ancient disease caused by the variola virus. Early symptoms include high

fever and fatigue. The virus then produces a characteristic rash, particularly on the face,

arms and legs. The resulting spots become filled with clear fluid and later, pus, and then

form a crust, which eventually dries up and falls off. Smallpox was fatal in up to 30% of

cases. Smallpox has existed for at least 3,000 years and was one of the worlds most

feared diseases until it was eradicated by a collaborative global vaccination programme

led by the World Health Organization. The last known natural case was in Somalia in

1977. Since then, the only known cases were caused by a laboratory accident in 1978 in

Birmingham, England, which killed one person and caused a limited outbreak. Smallpox

was officially declared eradicated in 1979.

Does it occur naturally?

Smallpox no longer occurs naturally since it was totally eradicated by a lengthy and

painstaking process, which identified all cases and their contacts and ensured that they

were all vaccinated. Until then, smallpox killed many millions of people.

How can I catch it and is it contagious?

The virus which causes smallpox is contagious and spreads through person-to-person

contact and saliva droplets in an infected persons breath. It has an incubation period of

between 7 and 17 days after exposure and only becomes infectious once the fever

develops. A distinctive rash appears two to three days later. The most infectious period

is during the first week of illness, although a person with smallpox is still infectious until

the last scabs fall off.

How fast does smallpox spread?


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The speed of smallpox transmission is generally slower than for such diseases as

measles or chickenpox. Patients spread smallpox primarily to household members and

friends because by the time patients are contagious, they are usually sick and stay in

bed; large outbreaks in schools were uncommon.

Werent the remaining stocks of the smallpox virus destroyed after smallpox

was eradicated?

When smallpox was officially certified as eradicated, in December 1979, an agreement

was reached under which all remaining stocks of the virus would either be destroyed or

passed to one of two secure laboratories one in the United States and one in the

Russian Federation. That process was completed in the early 1980s and since then no

other laboratory has officially had access to the virus which causes smallpox.

Then why is smallpox being talked about now?

Some governments believe there is a risk that the virus which causes smallpox exists in

places other than these laboratories and could be deliberately released to cause harm. It

is impossible to assess the risk that this might happen, but at their request, WHO is

making efforts to help governments prepare for this possibility.

Can it be treated?

There is no cure for smallpox, but vaccination can be used very effectively to prevent

infection from developing if given during a period of up to four days after a person has

been exposed to the virus. This is the strategy that was used to eradicate the disease

during the 20th century. New antiviral drugs, that have been developed for otherdiseases since smallpox was eradicated, may have a role. No studies of their usefulness,

or safety, have been conducted on humans exposed to smallpox.

Is a vaccine currently available?

There is a vaccine against smallpox and it was a key tool in the eradication of the

disease. The vaccine does not contain the Variola virus which causes smallpox , but a

closely related virus called vaccinia. When this vaccine is given to humans, it protects

them against smallpox. However, it can have very serious side effects, which in extreme

cases can be fatal. It has therefore not been recommended for the general public sincesmallpox was eradicated. It is used to protect researchers who work on the variola virus

that causes smallpox and other viruses in the same virus family (known as orthopox

viruses). It could also be used to protect anyone else judged to have a high risk of

exposure to smallpox. The vaccine cannot be used in people whose immune systems are

not functioning properly.

Should the smallpox vaccine be widely used to protect people?

Vaccination with the vaccinia virus as a protection against smallpox is not recommended

for widespread use. No government gives or recommends the vaccine routinely since it

can cause serious complications, and even death. It should be given only to those


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persons who have a high risk of coming into contact with the virus which causes

smallpox, or who have been exposed.

What can be done to protect people from smallpox?

Doctors, health workers and hospital personnel around the world have been trained to

identify infectious diseases, verify their diagnosis and then respond accordingly. The

same system would identify any possible outbreak of smallpox even if the virus is

deliberately spread to cause harm. The public health system would then be mobilized to

trace all known contacts of the infected person and vaccinate them to prevent more

cases of smallpox from developing. If this is done rapidly and effectively, the number of

cases could be kept to a minimum and the outbreak would be contained. This was the

approach which successfully eradicated the disease. The key is a good disease detection

system and a rapid response to infectious diseases, no matter what their cause. At this

time, several governments have started to examine the potency and levels of their

smallpox vaccine stocks, and to consider whether, and under what circumstances, to

obtain additional supplies.

I had the vaccination when I was a child. Am I still protected?

Anyone who has been vaccinated against smallpox (in most countries, this means

anyone aged 25-30 or over) will have some level of protection. The vaccination may not

still be fully effective, but it is likely to protect you from the worst effects of the disease.

However, if you were directly exposed to the virus which causes smallpox, a repeat

vaccination would be recommended.What is WHO doing now?

WHO receives information from governments and other sources on suspected

occurrences of unusual outbreaks, including smallpox. It provides technical guidance to

help them respond to these events. WHO has displayed practical information on smallpox

diagnosis, surveillance, and outbreak response on its web site. It can help countries

identify potential sources of vaccine, should such a need arise.

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What is Smallpox