Hepatitis C Virus Genotypes and Viral Concentrations in Participants of a General Population Survey in the United States

Nainan, Omana V.; Alter, Miriam J.; Kruszon-Moran, Deanna; Gao, Feng-Xiang; Xia, Guoliang; McQuillan, Geraldine; Margolis, Harold S.

doi:10.1053/j.gastro.2006.06.007

« Previous Next »Gastroenterology
Volume 131, Issue 2 , Pages 478-484, August 2006

Hepatitis C Virus Genotypes and Viral Concentrations in Participants of a General Population Survey in the United States

Omana V. Nainan
- Division of Viral Hepatitis, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
- Deceased.
Miriam J. Alter
- Institute for Human Infections and Immunity, University of Texas Medical Branch at Galveston, Galveston, Texas
- Address correspondence to: Miriam J. Alter, PhD, Institute for Human Infections and Immunity, University of Texas Medical Branch at Galveston, 301 University Blvd., Mail Route 0435, Galveston, Texas 77555. fax: (409) 772-6527.
Deanna Kruszon-Moran
- Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland
Feng-Xiang Gao
- Division of Viral Hepatitis, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
Guoliang Xia
- Division of Viral Hepatitis, National Center for Infectious Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia
Geraldine McQuillan
- Division of Health and Nutrition Examination Surveys, National Center for Health Statistics, Centers for Disease Control and Prevention, Hyattsville, Maryland
Harold S. Margolis
- International Vaccine Institute, Seoul, Korea

Received 12 June 2005; accepted 11 May 2006.

Background & Aims: Estimates of the long-term benefits of antiviral therapies for chronic hepatitis C are influenced by the frequency of characteristics that affect response in the population treated. This study determined hepatitis C virus (HCV) genotypes and RNA titers among HCV-infected persons in the general population of the United States.

Methods: Genotypes were determined from the NS5b region, and HCV RNA was quantified by using Amplicor Monitor (Roche Diagnostic Systems, Inc, Branchburg, NJ) from 275 HCV RNA–positive participants in the Third National Health and Nutrition Examination Survey conducted during 1988 to 1994.

Results: The HCV genotypes identified included 1a (n = 142), 1b (n = 73), 2a (n = 8), 2b (n = 27), 3a (n = 17), 4 (n = 3), and 6 (n = 5). Based on weighted analysis of persons infected with genotypes 1, 2, and 3, genotype 1 predominated in all age groups (75.3%). By racial/ethnic group, genotype 1 was found in 90.9% of non-Hispanic blacks, 69.6% of non-Hispanic whites, and 71.2% of Mexican Americans. After adjusting for age and gender, only non-Hispanic black race/ethnicity was independently associated with genotype 1 infection (adjusted odds ratio 4.9; 95% confidence interval, 1.9–12.8). The overall geometric mean concentration of HCV RNA was 2.1 × 10⁶ IU/mL; concentrations >2 million IU/mL were found in 53.0% overall and 50.3% of persons with genotype 1.

Conclusions: Persons with chronic hepatitis C in the United States who may require treatment in the foreseeable future are predominantly infected with genotype 1, including a disproportionate number of non-Hispanic blacks. These features emphasize the need for improved therapies that reduce or eliminate complications from genotype 1 infections.

Abbreviations used in this paper: CI, confidence interval , HCV, hepatitis C virus , NHANES III, Third National Health and Nutrition Examination Survey , SVR, sustained virologic response