Transmission of vaccine strain varicella-zoster virus from a healthy adult with vaccine-associated rash to susceptible household contacts

Twelve days after receiving an investigational Oka strain live attenuated varicella vaccine, a 38-year-old healthy white woman developed a rash consisting of 30 scattered lesions. Sixteen days later, her 2 children also developed rash. Swabs obtained from the skin lesions of the vaccinee and her children demonstrated the presence of varicella-zoster virus (VZV) DNA by a polymerase chain reaction (PCR) assay. Restriction endonuclease polymorphisms present in wild and vaccine type VZV were examined, and the amplified VZV DNA was determined to be vaccine type. This case documents transmission of varicella vaccine type virus from a healthy vaccinee to susceptible household contacts. Since vaccine-associated rashes are uncommon and mild, it is likely that transmission of vaccine virus will also be uncommon. With widespread immunization beginning in the United States, ongoing studies will define the frequency of this transmission.