Which of the following vaccines is live attenuated?

The correct answer is Zostavax, as it is a live attenuated vaccine specifically designed to protect against herpes zoster, commonly known as shingles. Live attenuated vaccines contain a weakened form of the virus or bacteria that causes the disease, which stimulates the immune system to build a protective response without causing the disease itself.

Zostavax is particularly important for older adults, as the incidence of shingles increases with age. The live attenuated form allows for a strong immune response, which significantly reduces the risk of developing shingles and its associated complications.

The other options, while important vaccines, do not fall into the category of live attenuated. Imovax Rabies is an inactivated vaccine, meaning the virus has been killed. Pneumovax 23 is also an inactivated vaccine that protects against pneumococcal disease, and Ipol is an inactivated poliovirus vaccine. Understanding the difference between live attenuated and inactivated vaccines is crucial for immunization practices, especially in determining the appropriate use and storage requirements for each type.