Open AccessEnumeration of an Extremely High Particle-to-PFU Ratio for Varicella-Zoster Virus
Author(s) -
John E. Carpenter,
Ernesto P. Henderson,
Charles Grose
Publication year - 2009
Publication title -
journal of virology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.617
H-Index - 292
eISSN - 1070-6321
pISSN - 0022-538X
DOI - 10.1128/jvi.00081-09
Subject(s) - varicella zoster virus , biology , virology , infectivity , enumeration , virus , titer , virus quantification , mathematics , combinatorics
Varicella-zoster virus (VZV) is renowned for its low titers. Yet investigations to explore the low infectivity are hampered by the fact that the VZV particle-to-PFU ratio has never been determined with precision. Herein, we accomplish that task by applying newer imaging technology. More than 300 images were taken of VZV-infected cells on 4 different samples at high magnification. We enumerated the total number of viral particles within 25 cm2 of the infected monolayer at 415 million. Based on these numbers, the VZV particle:PFU ratio was approximately 40,000:1 for a cell-free inoculum.