• At this time, ACIP does not recommend vaccination of the general public, as the potential benefits of the vaccine do not outweigh the risks of adverse events.
• ACIP continued to recommend so-called "ring vaccination" also referred to as "search and containment."
• For the past year, ACIP has supported ring vaccination as the most efficient use of smallpox vaccine with the fewest number of adverse side effects. The strategy is based on information that vaccination within three to four days of contact with an infectious case can prevent or lessen the severity of the disease.
• In the ring vaccination strategy, contacts of people with smallpox and contacts of these contacts would be vaccinated immediately. This would form concentric "rings" of immunized people around infectious cases (who would be isolated). This will reduce the chance of transmission to susceptible people.
• The committee also recommended that selected personnel, those who would care for patients at predesignated smallpox isolation and care centers, should be vaccinated. Bioterrorism and public health officials would identify the facilities, while hospitals would decide which personnel should be inoculated.

What are the AAP's recommendations?

• The AAP Committee on Infectious Diseases has been drafting a smallpox policy statement that will be ready this fall. It is expected to mirror the ACIP recommendations.

If another terrorist attack or threat makes routine immunization necessary, would the U.S. be ready?

• There may be enough vaccine to immunize the entire U.S. population by the end of 2002.
• Until recently, it was believed that the amount of vaccine available would be sufficient to immunize only a small fraction of the U.S. population. Currently, approximately 15 million doses of vaccine are stocked in a lyophilized frozen state by the CDC. New data suggest that the vaccine may be diluted at least 1:5 to 1:10 and still provide a satisfactory response. Additionally, about 85 million doses of concentrated smallpox vaccine put aside by Aventis Pasteur are being shipped to the CDC.
• All of this vaccine, plus vaccine produced under recently signed government contracts, would be considered investigational, since U.S. Food and Drug Administration approval of older vaccine has lapsed. This would limit the use of vaccine unless a disaster were declared.

Are we expecting a smallpox attack?

• We are not expecting a smallpox attack, but the recent events that include the use of anthrax as a weapon have heightened our awareness of the possibility of such an attack.

Is there an immediate smallpox threat?

• At this time we have no information that suggests an imminent smallpox threat.
• The last naturally acquired case of smallpox in the world occurred in 1977. The last cases of smallpox, from laboratory exposure, occurred in 1978. However, reports that smallpox virus may have been given to facilities other than the designated laboratories in the US and Russia is the source of some concern about the possibility of a threat.

If I am concerned about a smallpox attack, can I go to my doctor and request the smallpox vaccine?

• In the United States, routine vaccination against smallpox ended in 1972. Since the vaccine is no longer recommended, the vaccine is not available.
• The CDC maintains an emergency supply of vaccine that can be released if necessary.

If I want the smallpox vaccine and I'm willing to accept the risks, why shouldn't I be allowed to have it?

• Because it is not only the individual receiving the vaccine who is put at risk. The smallpox vaccine causes each person who gets it to develop a sore or "pox" at the point of injection that is teeming with the virus. That person is now contagious for up to 21 days.
• The virus can spread from a recently immunized person to other people. Those at particularly high risk are young children, the elderly, and people who have altered immune systems from cancer, chemotherapeutic drugs, or AIDS. For all those people, the result could be a life-threatening or life-ending infection.
• Complications of vaccination have been treated with vaccinia immune globulin in the past. There are only 600 doses of this material in the US. If we allowed for random vaccination, this medicine would soon be used up, meaning it would not be available all those who would need it.

If someone is exposed to smallpox, is it too late to get a vaccination?

• If the vaccine is given within 4 days after exposure to smallpox, it can lessen the severity of illness or even prevent it.

If someone comes in contact with smallpox, how long does it take to show symptoms?

• The incubation period is about 12 days (range: 7 to 17 days) following exposure.
• Initial symptoms include high fever, fatigue, and head and backaches.
• The characteristic rash, most prominent on the face, arms, and legs, follows in 2-3 days. The rash starts with flat, red sores that evolve at the same rate. The sores become pus-filled after a few days and then begin to crust early in the second week. Scabs develop and then separate and fall off after about 3-4 weeks, possibly leaving pitted scars.

Is smallpox fatal?

• The majority of patients with smallpox recover, but death may occur in up to 30% of cases.

How is smallpox spread?

• In the majority of cases, smallpox is spread from one person to another by infected saliva droplets that expose a susceptible person having face-to-face contact with the ill person.
• People with smallpox are most infectious during the first week of illness after the rash develops, because that is when the largest amount of virus is present in saliva. However, some risk of transmission lasts until all scabs have fallen off.
• Contaminated clothing or bed linen could also spread the virus. Special precautions need to be taken to ensure that all bedding and clothing of patients are cleaned appropriately with bleach and hot water. Disinfectants such as bleach and quaternary ammonia can be used for cleaning contaminated surfaces.

If people got the vaccination in the past when it was used routinely, will they be immune?

• Not necessarily.
• Routine vaccination against smallpox ended in 1972. The level of immunity, if any, among people who were vaccinated before 1972 is uncertain; therefore, these people are assumed to be susceptible.
• For those who were vaccinated, it is not known how long immunity lasts. Most estimates suggest immunity from the vaccination lasts 3 to 5 years. A single revaccination can effectively boost immunity.

Is it possible for people to get smallpox from the vaccination?

• No, smallpox vaccine does not contain smallpox virus but another live virus called vaccinia virus. Since this virus is related to smallpox virus, vaccination with vaccina provides immunity against infection from smallpox virus.

How safe is the smallpox vaccine?

• Smallpox vaccine is considered safe. However, some people with pre-existing conditions such as eczema or immune system disorders have a higher risk for having complications from the vaccine.
• Adverse reactions have been known to occur that range from mild rashes to fatal brain infection and disseminated vaccina. Smallpox vaccine should not be administered to people with a history or presence of eczema or other skin conditions, pregnant women, or people with immunodeficiency diseases and among those with suppressed immune systems as occurs with leukemia, lymphoma, generalized malignancy, or solid organ transplantation.
• Caution should be used in vaccinating individuals who have contact with people who are at high risk for complications, because the vaccine virus can spread from a vaccinated individual to an unvaccinated, high-risk individual.

Is there any treatment for smallpox?

• There is no proven treatment for smallpox, but research to evaluate new antiviral agents is ongoing.
• Patients with smallpox can benefit from supportive therapy (e.g., intravenous fluids, medicine to control fever or pain) and antibiotics for any secondary bacterial infections that may occur.

How can we stop the spread of smallpox after someone comes down with it?

• Patients should be placed in medical isolation so that they will not continue to spread the virus. In addition, people who have come into close contact with smallpox patients should be vaccinated immediately and closely watched for symptoms of smallpox. Vaccine and isolation are the strategies for stopping the spread of smallpox.
• Your doctor has access to guidelines prepared by the CDC for evaluating and responding to a suspected smallpox outbreak.

Adapted from FAQ's prepared by the Centers for Disease Control and Prevention, 5-02