If a person develops a rash after receiving varicella vaccination, does he need to be isolated from susceptible people who are either pregnant or immunosuppressed?

Transmission of varicella vaccine virus is rare. However, if a pregnant or immunosuppressed household contact of a vaccinated person is known to be susceptible to varicella, and if the vaccinee develops a rash 7 to 21 days following vaccination, it is prudent that they avoid prolonged close contact with the susceptible person until the rash resolves.