Questions: A client taking oral corticosteroids is exposed to varicella. The client has never had the disease and has not received the varicella vaccine. What intervention should the nurse anticipate in order to prevent the client from developing varicella? Administer a course of oral acyclovir. Administer the varicella vaccine as soon as possible. Obtain a blood specimen for a varicella titer Administer varicella zoster immune globulin (VZIG)

The answer is the fourth one: Administer varicella zoster immune globulin (VZIG).

Explanation for each option:

1. Administer a course of oral acyclovir: Acyclovir is an antiviral medication that can be used to treat varicella (chickenpox) once the infection has occurred, but it is not typically used as a preventive measure immediately after exposure.

2. Administer the varicella vaccine as soon as possible: While the varicella vaccine is effective in preventing the disease, it is generally not recommended for immediate post-exposure prophylaxis in individuals who are immunocompromised or taking immunosuppressive medications like corticosteroids. The vaccine is more effective when given before exposure.

3. Obtain a blood specimen for a varicella titer: This test would determine if the client has immunity to varicella, but it does not provide immediate protection against the disease. Given the client's history of never having had the disease or the vaccine, it is likely they are not immune.

4. Administer varicella zoster immune globulin (VZIG): VZIG is recommended for post-exposure prophylaxis in individuals who are at high risk for severe varicella, such as those taking immunosuppressive medications like corticosteroids. It provides immediate passive immunity to help prevent the development of varicella.

Summary: The most appropriate intervention to prevent the client from developing varicella after exposure, given their lack of prior immunity and current use of oral corticosteroids, is to administer varicella zoster immune globulin (VZIG).