Temporal changes in HCV genotype distribution in three different high risk populations in San Francisco, California
1 Núcleo de Estudos e Pesquisas em Atenção ao Uso de Drogas (NEPAD)- Universidade do Estado do Rio de Janeiro (State University of Rio de Janeiro), R Fonseca Teles 121, 4°. Andar; 20940-200 Rio de Janeiro, RJ, Brasil
2 Department of Epidemiology and Biostatistics, Division of Preventive Medicine and Public Health, Box 1224, 50 Beale Street 1200 University of California San Francisco, San Francisco, CA USA
3 Department of Medicine, Division of Infectious Disease, San Francisco General Hospital, Box 0811, SFGH Bldg 100 335; University of California San Francisco, San Francisco, CA. 94143 - 0811, USA
4 Blood Systems Research Institute, 270 Masonic Avenue, San Francisco, CA 94118, USA
5 Department of Medicine, SUNY Downstate College of Medicine, 450 Clarkson Avenue, Box 1240, Brooklyn, NY 11203. USA
6 Department of Epidemiology and Biostatistics, Division of Clinical Epidemiology, Box 0560, 185 Berry Street 5700, University of California San Francisco, San Francisco, CA. 94143 - 0560, USA
7 Department of Medicine, Positive Health Program, San Francisco General Hospital, Box 0874, SFGH Bldg 100 335; University of California San Francisco, San Francisco, CA. 94143 - 0811, USA
8 Research Triangle Institute (RTI), San Francisco, CA USA
9 Department of Laboratory Medicine, Box 0134, University of California San Francisco San Francisco, CA. 94143 - 0134 USA
BMC Infectious Diseases 2011, 11:208 doi:10.1186/1471-2334-11-208Published: 2 August 2011
Hepatitis C virus (HCV) genotype (GT) has become an important measure in the diagnosis and monitoring of HCV infection treatment. In the United States (U.S.) HCV GT 1 is reported as the most common infecting GT among chronically infected patients. In Europe, however, recent studies have suggested that the epidemiology of HCV GTs is changing.
We assessed HCV GT distribution in 460 patients from three HCV-infected high risk populations in San Francisco, and examined patterns by birth cohort to assess temporal trends. Multiple logistic regression was used to assess factors independently associated with GT 1 infection compared to other GTs (2, 3, and 4).
Overall, GT 1 was predominant (72.4%), however younger injection drug users (IDU) had a lower proportion of GT 1 infections (54.7%) compared to older IDU and HIV-infected patients (80.5% and 76.6%, respectively). Analysis by birth cohort showed increasing proportions of non-GT 1 infections associated with year of birth: birth before 1970 was independently associated with higher adjusted odds of GT 1: AOR 2.03 (95% CI: 1.23, 3.34). African-Americans as compared to whites also had higher adjusted odds of GT 1 infection (AOR: 3.37; 95% CI: 1.89, 5.99).
Although, HCV GT 1 remains the most prevalent GT, especially among older groups, changes in GT distribution could have significant implications for how HCV might be controlled on a population level and treated on an individual level.