May 2003

The Smallpox Vaccine Program: Essential Information for the OSH Professional

Peter Greaney, MD
Board-Certified Occupational Physician
President, WorkCare

As the war in Iraq nears its final stages, efforts to prepare our homeland against the threat of bioterrorism continue to move forward. The U.S. Centers for Disease Control and Prevention (CDC) reported that more than 33,444 U.S. healthcare workers and public officials received the smallpox vaccine from the period of January to April 2003. In addition, approximately 325,000 military personnel have received the smallpox vaccine. The smallpox vaccine is being administered on a voluntary basis to first responders, healthcare response teams, military, and public officials as a measure to protect people from the intentional release of a smallpox virus that could potentially occur through an act of terrorism. This article outlines the risks and guidelines associated with smallpox vaccinations, providing need-to-know information for the OSH professional who may serve as a first responder, or whose work is impacted by the government's smallpox response plan.

Background on Smallpox

Smallpox is caused by the variola virus. It is a serious, acute, contagious, and sometimes fatal disease that kills up to 30 percent of those infected by the virus. It is so dangerous that the CDC has classified smallpox as a Category A agent, which is a category for diseases believed to pose the greatest threat to public health. Anthrax, botulism and plague are also Category A agents.

Its symptoms include fever and a distinctive progressive skin rash that can leave scars when healed. It can also cause high fever, tiredness, severe headaches backache and blindness.

The disease is spread from person to person through close contact.

The disease was eradicated in the 1980s through mass vaccination efforts and ring vaccination methods (smallpox vaccines given to selected people who were exposed to an infected person). The last confirmed case of smallpox in the United States occurred in 1949, and in 1997 the world had its last confirmed case of smallpox, which occurred in Somalia . In 1980, the World Health Organization declared that smallpox had been eradicated.

The New Smallpox Vaccine Program

The September 11 terrorist attacks and other world events have heightened government concern that hostile groups or governments may have access to the smallpox virus and use it as a bioterrorist weapon against the American public. In responding to this threat, President Bush announced a smallpox vaccination plan directed to first responders (emergency department physicians, nurses, aides, state and local health officials, emergency medical services staff/technicians, police, firefighters and rescue workers). The smallpox vaccine is a highly effective measure to protect against the disease when given before or shortly after exposure to the virus. Under the plan, the Department of Health and Human Services (HHS) will work with state and local governments to form volunteer Smallpox Response Teams who can provide critical services to the public in the event of a smallpox attack.

HHS is working with states to identify healthcare workers and first responders to serve on Smallpox Response Teams. Pre-attack vaccination of these Smallpox Response Teams will allow these teams to immediately administer the vaccine to others in case of a smallpox attack.

In addition, the CDC reports that the United States currently has sufficient quantities of the vaccine to vaccinate every single person in the country in case of a bioterrorism event.

Vaccination of the general public is not recommended by the plan at this time.

About The Vaccine (Excerpt from the CDC Document, Smallpox VIS 1/16/03 )

Smallpox vaccine is made from a virus called vaccinia. Vaccinia virus is similar to the smallpox virus, but less harmful. Vaccinia vaccine can protect people from smallpox. The vaccine does not contain the smallpox virus. Getting the vaccine before exposure will protect most people from smallpox. Getting the vaccine within 3 days after exposure can prevent the disease or at least make it less severe. Getting the vaccine within a week after exposure can still make the disease less severe. Protection from infection lasts 3 to 5 years, and protection from severe illness and death can last 10 years or more.

Risks of the Smallpox Vaccine

The following information is about known reactions to smallpox vaccine. A vaccine, like any medicine, can cause serious problems, including those we do not yet know about, as well as severe allergic reactions. The risk of smallpox vaccine causing serious harm, or death, is very small.

Mild to Moderate Problems

Mild rash, lasting 2-4 days
Fever of over 100º F (about 10% of adults)
Blisters elsewhere on the body (about 1 per 1,900)

About one-third of people getting the vaccine may feel sick enough to miss work or school or curtail recreational activities, or may have temporary trouble sleeping.

Moderate to Severe Problems (That Need Immediate Medical Attention)

Eye infection due to spread of vaccine virus to the eye, which can lead to loss of vision
Rash on entire body (as many as 1 per 4,000), which usually resolves without problems

Potentially Life-Threatening Problems

Severe rash on people with eczema or atopic dermatitis (as many as 1 per 26,000), which can lead to scarring or death
Encephalitis (severe brain reaction--as many as 1 per 83,000), which can lead to permanent brain damage or death
Severe progressive infection beginning at the vaccination site (as many as 1 per 667,000, mostly people with weakened immune systems), which can lead to scarring or death.

For every million people vaccinated in the past, between 14 and 52 people had a life-threatening reaction to smallpox vaccine and 1-2 died.

If you have a reaction to the vaccine, ask your doctor or nurse to file a Vaccine Adverse Event Report (VAERS form) and contact their health department. You can also file a report yourself by visiting the VAERS website at http://www.vaers.org or calling 1-800-822-7967.

Who Should Not Receive The Vaccine
(During Routine, Non-emergency Use--No Outbreak)

Anyone who has eczema or atopic dermatitis, or has a past history of either condition, should not get smallpox vaccine
Anyone with a skin condition that causes breaks in the skin (such as an allergic rash, severe burn, impetigo, chickenpox, shingles, or severe acne) should wait until the condition clears up before getting smallpox vaccine
Anyone whose immune system is weakened should not get smallpox vaccine, including anyone who:

Has HIV/AIDS or another disease that affects the immune system
Has significant immune system suppression from a severe autoimmune disease, such as systemic lupus erythematosus
Is being treated, or has recently been treated, with drugs that affect the immune system, such as steroids, some drugs for autoimmune disease, or drugs taken in association with an organ or bone marrow transplant
Has leukemia, lymphoma, or most other cancers
Is taking cancer treatment with x-rays or drugs, or has taken such treatment in the past 3 months
Pregnant women should not get smallpox vaccine

Additional Conditions That Require Avoidance or Delay of The Vaccine

Women should avoid getting pregnant for 4 weeks after getting smallpox vaccine.
Smallpox vaccine is not recommended for anyone under 18 years of age.
Do not get smallpox vaccine if you have ever had a life-threatening allergic reaction to polymyxin B, streptomycin, chlortetracycline, neomycin, or a previous dose of smallpox vaccine .
Breastfeeding mothers should not get smallpox vaccine
Persons using steroid drops in their eyes should not get smallpox vaccine.
People who are moderately or severely ill at the time the vaccination is scheduled should usually wait until they recover before getting smallpox vaccine.

Individuals who live with or have close physical contact with someone who falls into any of the above categories should not get smallpox vaccine because of the risk it poses to that close contact. (Close contacts include anyone living in your household and anyone you have close physical contact with, such as a sex partner. They do not include friends or people you work with.)

These above restrictions may not apply in the event of a smallpox outbreak in which emergency vaccination may be required.

Updated Restrictions On Smallpox Vaccine

Just recently, the CDC changed the smallpox vaccine recommendation after three heart attack deaths in vaccinated individuals. Even though the cases were not definitively linked to the immunization, the CDC has recommended that anyone with a history of heart disease or those with three or more major risk factors for heart disease be excluded from the vaccination program.

Following are the CDC recommendations, released in March 2003, of those people who should be excluded from the pre-event smallpox vaccination program:

Have been diagnosed by a doctor as having a heart condition with or without symptoms, including conditions such as previous myocardial infarction (heart attack), angina (chest pain caused by lack of blood flow to the heart), congestive heart failure, cardiomyopathy (heart muscle becomes inflamed and doesn't work as well as it should), stroke or transient ischemic attack (a "mini-stroke" that produces stroke-like symptoms but not lasting damage), chest pain or shortness of breath with activity (such as walking up stairs), or other heart conditions being treated by a doctor. (While this may be a temporary exclusion, these people should not get the vaccine at this time.)
Have 3 or more of the following risk factors: high blood pressure diagnosed by a doctor; high blood cholesterol diagnosed by a doctor; diabetes or high blood sugar diagnosed by a doctor; a first degree relative (for example, mother, father, brother, sister) who had a heart condition before the age of 50; and, you smoke cigarettes now. (While this may be a temporary exclusion, these people should not get the vaccine at this time.)

In addition to these guidelines, the following links provide additional reference material on Smallpox and The Vaccine Program.

For more information, please visit any of the following links:

Smallpox Information and Resources
CDC Smallpox Homepage
http://www.cdc.gov/smallpox

Journal Articles, Links and Immunization Information
Immunization Action Coalition
http://www.immunize.org/bioterror/smallpox.htm

An Update on Smallpox
By Michelle Meadows, FDA
http://www.fda.gov/fdac/features/2003/203_smallpox.html

Vaccine Overview
Fact Sheet by CDC
http://www.bt.cdc.gov/agent/smallpox/vaccination/facts.asp

CDC's Smallpox Preparation and Response Activities
CDC Public Health Emergency Preparedness and Response
http://www.bt.cdc.gov/agent/smallpox/prep/cdc-prep.asp

Smallpox Vaccine and Heart Problems: Information for People Who Have Recently Received the Smallpox Vaccine
CDC Fact Sheet
http://www.bt.cdc.gov/agent/smallpox/vaccination/cardiacrecentvaccinees.asp

Update: Adverse Events Following Civilian Smallpox Vaccination, United States, 2003
CDC Morbidity and Mortality Weekly Report, April 25 2003
http://www.cdc.gov/mmwr/preview/mmwrhtml/mm5216a2.htm

Temporary Deferral Recommended for Heart Patients Volunteering for Smallpox Vaccination
CDC Press Release
http://www.cdc.gov/od/oc/media/pressrel/r030325.htm

"Smallpox Vaccination--The Call to Arms"
Authors: Schraeder TL, Campion EW
Source: New England Journal of Medicine, January 30, 2003 , Vol. 348(5):381-382
http://content.nejm.org/cgi/content/full/348/5/381

Health Center Doctors First To Receive Smallpox Vaccine
Article by University of Connecticut
http://www.advance.uconn.edu/03020302.htm