Cancer Treatment & the Vaccinia Virus

Smallpox, a highly-contagious disease caused by the vaccinia virus, was first identified in India or Egypt more than 3,000 years ago. In 1980, the World Health Organization (WHO) confirmed that the vaccinia vaccine had effectively eradicated smallpox around the world.

Identification

• The form of vaccinia vaccine currently approved for use in the U.S. is known as Dryvax. According to the Centers for Disease Control (CDC), this vaccine contains a live-virus preparation of the infectious smallpox virus.

Effect

• Once the vaccinia virus is injected into a person, the individual will begin developing antibodies to the live virus. As antibody levels rise, the person has some degree of protection against smallpox.

Considerations

• Certain forms of cancer, such as leukemia and lymphoma, suppress the immune system. Cancer treatments such as radiation, chemotherapy and stem cell or organ transplants, also suppress the immune system.

Significance

• If an individual's immune system is suppressed, the vaccinia virus may replicate, or copy itself, at a rapid rate. As his viral load increases, he's at increased risk of developing symptoms of smallpox.

Expert Insight

• The CDC says people who are immunosuppressed---as well as their household contacts--should not receive the vaccinia vaccine.