Use of genomic analysis of varicella-zoster virus to investigate suspected varicella-zoster transmission within a renal unit.

BACKGROUND: The source of hospital-acquired chickenpox infection may be presumed from a known exposure, but has not been previously proven using genomic analysis. OBJECTIVE: Investigation of suspected VZV transmission was done using single nucleotide polymorphism genomic analysis. STUDY DESIGN: Comparison was made of viral isolates from two patients with chickenpox on the same ward who were not known to have had direct contact. RESULTS: An identical genotype in the variable R1 region of the VZV was isolated from the two patients. CONCLUSION: Inapparent hospital-acquired transmission was the most likely route of infection.