Public Health

What Is Smallpox?

Smallpox is a severe, contagious and sometimes fatal disease caused by the variola virus. Those infected often have a fever and a distinctive skin rash. The last case of smallpox in the U.S. occurred in 1949, and because of vaccinations, the disease was declared eradicated by the World Health Organization in 1980. However, some strands of the disease remained in laboratories in the U.S., the Soviet Union, and possible other countries. In the aftermath of the events of September and October, 2001, the U.S. government is taking precautions to be ready for a bioterrorist attack using smallpox as a weapon.

The symptoms of smallpox begin with a high fever, head and body aches and sometimes vomiting. A rash follows that spreads and progresses to raised bumps and pus-filled blisters that crust, scab and fall off after about three weeks, leaving a pitted scar. After exposure, it takes between 7 and 17 days for symptoms of smallpox to appear (average incubation time is 12 to 14 days). During this time, the infected person feels fine and is not contagious.

The majority of smallpox patients will recover, but death may occur in up to 30 percent of cases. Many smallpox survivors have permanent scars over large areas of their body, especially their face. Some are left blind.

Who can get it and how does it spread?

Anyone not vaccinated for smallpox is susceptible to the disease. Inoculations provide 100 percent immunity but people must be revaccinated to maintain total resistance.

Smallpox normally spreads from contact with infected persons. Generally, direct and fairly prolonged face-to-face contact is required to spread smallpox from one person to another.

Smallpox also can be spread through direct contact with infected bodily fluids or contaminated objects like bedding or clothing. Indirect spread is less common. Rarely, smallpox has been spread by airborne viruses in enclosed areas such as buildings, buses and trains.

Are there side effects to the smallpox vaccination?

Most people experience mild reactions that include a sore arm, fever, and body aches. However, the vaccine does have some adverse risks. In recent tests, 1 in 3 people felt bad enough to miss work, school or recreational activity or had trouble sleeping after receiving the vaccine. Rarely, people have had severe reactions to the vaccine. In the past, between 14 and 52 people per 1 million vaccinated experienced potentially life-threatening reactions. It is estimated that 1 or 2 out of every 1 million people vaccinated will die as a result of complications from the vaccine.

The CDC has refrained from any attempt to quantify the number of people vaccinated who might experience adverse reactions to the vaccine. A large percentage of the population being vaccinated today has not been vaccinated before, making estimates for how they will respond to the vaccination impossible to make.

Who shouldn’t get the smallpox vaccine?

Some people are more likely to experience adverse reactions. You should not receive the vaccine if you or a household contact has the following:

- Eczema or atopic dermatitis (this is true even if the condition is not currently active, mild or experienced as a child)

- Other skin conditions such as burns, chickenpox, shingles, impetigo, herpes, severe acne, psoriasis or Darier’s disease (if you suffer from any of these conditions, you should not get the vaccine until you have completely healed).

- Weakened immune system (cancer treatment, an organ transplant, HIV, or medications such as maintenance steroids to treat autoimmune disorders and other illnesses can weaken the immune system).

- Pregnancy or plans to become pregnant within one month of vaccination.

- Allergies to the vaccine or any of its ingredients.

- Moderate or severe short-term illnesses (you should wait to receive the vaccine until you have completely recovered).

- Younger than 18 years of age.

- Breast-feeding mothers should not get smallpox vaccine.

Those who choose to receive the smallpox vaccination will receive literature about smallpox and the vaccine well before their vaccination day. A health professional will then review the information with the vaccinees and they must sign a consent form before receiving the vaccination.

Is there an upper age cut-off for vaccine recipients in a non-emergency setting?

There are no published data that supports the use of smallpox vaccine in a population older than 65 years of age and up. It is not recommended in this group in a non-emergency situation.

Have the liability and worker’s compensation issues been settled yet?

Congress, the CDC, the Department of Health and Human Services and state health departments are working closely together in an effort to solve the problems surrounding liability and worker’s compensation issues before vaccinations begin. As the waters become less murky, we will send updates.

What criteria did Wyoming use in determining who should be vaccinated?

The state is working with hospitals and county officials to identify the appropriate personnel to be vaccinated. The goal is to vaccinate those people who would respond to the initial cases of smallpox, as well as those people who could begin giving smallpox vaccinations in an emergency. Each hospital will have a healthcare response team which will be vaccinated and prepared to care for one or more initial cases of smallpox in their respective counties.

For more information, please contact:

Dr. Karl Musgrave, State Epidemiologist, Wyoming Department of Health
office: (307) 777-7958

Ross Doman, Public Information Officer, Wyoming Department of Health
office: (307) 777-6420 / cell: (307) 631-0699 / email: rdoman@state.wy.us

Daniel Kessler, Risk Communication Specialist, Wyoming Department of Health
office: (307) 777-8924 / cell: (307) 631-8680 / email: dkessl1@state.wy.us