Herpes zoster and exposure to the varicella zoster virus in an era of varicella vaccination.
OBJECTIVE
We performed a case-control study to determine if participants with herpes zoster had fewer contacts with persons with varicella or zoster, and with young children, to explore the hypothesis that exposure to persons with varicella zoster virus (VZV) results in "immune boosting."


METHODS
Participants were patients of the multispecialty Marshfield Clinic in Wisconsin. We identified patients aged 40 to 79 years with a new diagnosis of zoster from August 2000 to July 2005. We frequency matched control participants to case participants for age. We confirmed diagnoses by chart review and assessed exposures by interview.


RESULTS
Interviews were completed by 633 of 902 eligible case participants (70.2%) and 655 of 1149 control participants (57.0%). The number of varicella contacts was not associated with zoster; there was no trend even at the highest exposure level (3 or more contacts). Similarly, there was no association with exposure to persons with zoster or to children, or with workplace exposures.


CONCLUSIONS
Although exposure to VZV in our study was relatively low, the absence of a relationship with zoster reflects the uncertain influence of varicella circulation on zoster epidemiology.
Donahue
James G
JG
Epidemiology Research Center, ML-2, Marshfield Clinic Research Foundation, 1000 N Oak Ave, Marshfield, WI 54449, USA. donahue.james@mcrf.mfldclin.edu
Kieke
Burney A
BA
Gargiullo
Paul M
PM
Jumaan
Aisha O
AO
Berger
Nicholas R
NR
McCauley
Jeremy S
JS
Belongia
Edward A
EA
D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D019433:Chickenpox Vaccine / Q000276:immunology*; D002648:Child; D005190:Family; D005260:Female; D006562:Herpes Zoster / Q000453:epidemiology* / Q000209:etiology; D014645:Herpesvirus 3, Human; D006801:Humans; D008297:Male; D008875:Middle Aged; D016273:Occupational Exposure / Q000706:statistics & numerical data; D016017:Odds Ratio; D012044:Regression Analysis; D014922:Wisconsin / Q000453:epidemiology
D019433:Chickenpox Vaccine