A prospective study to examine persistent HCV reinfection in injection drug users who have previously cleared the virus.
BACKGROUND
Many HCV-infected persons with recent or ongoing injection drug use (IDU) do not receive HCV treatment due to the perceived risk of HCV reinfection. There are few prospective studies investigating HCV reinfection among IDUs.


METHODS
Two hundred and twenty-four persons with past or ongoing IDU were followed from 1997 to 2007. Baseline and every 6-month follow-up data were collected including demographics, IDU, and sexual behaviors. Serum was tested for the presence of HCV antibody and serially for HCV RNA. Resolvers were defined as HCV antibody and RIBA positive and RNA negative at two consecutive time points or as becoming HCV RNA negative after HCV antiviral treatment. Reinfection was defined by the presence of HCV RNA at > or =2 visits.


RESULTS
One hundred and eighty-six persons had chronic HCV and 38 had resolved HCV. The resolvers were followed for a total of 214 person-years. Forty-two percent of resolvers reported ongoing IDU, representing 58 person-years of IDU. Only one reinfection occurred in the resolvers, for a reinfection rate of 0.47 cases/100 person-years of follow-up. The single reinfection, which occurred in a person who continued to inject drugs, represents a reinfection rate of 1.75 cases/100 person-years of IDU.


CONCLUSIONS
These data suggest that despite ongoing IDU, persistent HCV reinfection is lower than previously published. This can be attributed to a more clinically relevant definition of reinfection. This information will better help clinicians make informed decisions regarding HCV treatment options for patients who may continue to inject illicit drugs.
Currie
Sue L
SL
Department of Medicine, University of California San Francisco, San Francisco, CA 94121, USA. sue.currie@va.gov
Ryan
James C
JC
Tracy
Daniel
D
Wright
Teresa L
TL
George
Sally
S
McQuaid
Rosemary
R
Kim
Michael
M
Shen
Hui
H
Monto
Alexander
A
D000437:Alcoholism / Q000453:epidemiology; D003710:Demography; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D005500:Follow-Up Studies; D006304:Health Status; D016174:Hepacivirus / Q000235:genetics / Q000302:isolation & purification; D006526:Hepatitis C / Q000453:epidemiology* / Q000276:immunology / Q000821:virology*; D006801:Humans; D008297:Male; D008875:Middle Aged; D015995:Prevalence; D011446:Prospective Studies; D012367:RNA, Viral / Q000235:genetics; D012008:Recurrence; D015819:Substance Abuse, Intravenous / Q000453:epidemiology*; D011795:Surveys and Questionnaires
D012367:RNA, Viral