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This vaccine protects against smallpox and monkeypox


Active ingredients:

The active ingredient in this vaccine is a live, attenuated version of vaccinia virus that cannot replicate. Vaccinia virus is a relative of smallpox and monkeypox that provides protection against both of these diseases. The vaccine is grown in chicken embryo cells, and the final vaccine may contain traces of DNA and proteins from these cells. 

Inactive ingredients:
Amounts are based on a 0.5 mL dose

Salts: help maintain the stability and pH of the vaccine

Antibiotics: prevent contamination during manufacturing


Relevant Terms:

  • Antibiotics: substances that kill bacteria or prevent them from dividing. Antibiotics are used in some vaccines to prevent contamination during the manufacturing process.

  • Attenuated: The pathogen is weakened but not completely inactivated. Attenuated pathogens are too weak to cause disease in almost all people.

  • pH: a measure of how acidic or basic a solution is. The scale ranges from 0 (very acidic) to 14 (very basic). A pH of 7 is neutral.

Relevant Terms


Last updated: Mar. 2, 2023

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