Background: Predominant modes of hepatitis C virus (HCV) transmission vary between countries and over time.
Aims: To compare HCV transmission modes in the USA and northern China.
Methods: We conducted a prospective study enrolling two cohorts of chronic HCV patients in the USA, and in China at Beijing, and at Gu'an and Kuancheng counties in Hebei. Patients self-reported the most likely source and year of infection.
Results: A total of 1957 patients were studied (1000 USA; 957 China-428 Beijing, 387 Gu'an, 142 Kuancheng). The predominant infection sources were transfusion (23.0%) and injection drug use (IDU) (32.1%) in the USA and transfusion (64.5%) in northern China. Within China, transfusion was the most common source in Beijing (62.1%) and Gu'an (88.1%), and medical procedures (35.9%) and IDU (12.0%) in Kuancheng. Infection via transfusion decreased significantly in the USA (35.1-4.6%) and Beijing (84.2-14.3%) but remained frequent in Gu'an (90.5-72.5%) over time. Infection via IDU decreased from 32.4% in those ≥61 years to 25.0% in those 41-50 years but increased to 46.5% in those ≤40 years in US patients and decreased over time from 38.7 to 1.9% in Kuancheng. Infection via medical procedures increased over time in Beijing (7.0-33.3%) and remained frequent in Kuancheng (45.2-31.1%).
Conclusions: There are major differences in presumed HCV infection source between the USA and northern China. Favorable as well as worrisome changes in the modes of HCV transmission in both countries were observed.
Keywords: Blood transfusion; Epidemiology; Hepatitis C virus; Injection drug use; Medical procedures.