Objectives: Despite an abundance of epidemiological evidence for horizontal transmission of hepatitis B virus (HBV), the transmission route remains to be fully elucidated. In a new approach, we evaluated quantitative HBV DNA content in serum, saliva and urine as a first step in exploring possible modes of horizontal transmission. Methods: In an outpatient setting of an academic hospital, paired serum, saliva and urine samples were collected from 150 chronically infected HBV patients. A validated HBV DNA TaqMan assay was used to quantitatively measure HBV DNA. Results: Mean log HBV DNA in serum was 5.8 (range, undetectable to 10.0 log HBV DNA) copies/ml, 50% of the patients had an HBV DNA above 10 5 copies/ml in serum. Mean log HBV DNA level in saliva was 3.2 (range, undetectable to 7.5) copies/ml, 15% had an HBV DNA above 10 5 copies/ml in saliva. Mean log HBV DNA level in urine was 2.6 (range, undetectable to 5.4) copies/ml and 1% had an HBV DNA above 10 5 copies/ml in urine. A high, non-linear correlation was shown between HBV DNA in serum and saliva (Spearman's rho 0.82) and between serum and urine (Spearman's rho 0.74). Conclusions: The significant amounts of HBV DNA found in saliva and urine in chronic HBV patients with high viraemia in serum may have implications for the understanding of hepatitis B epidemiology. The potential infectivity of these body fluids may provide an explanation for the 20% of cases of infection obtained through horizontal transmission for which the origin of infection is yet unknown.

Additional Metadata
Keywords Body fluids, Epidemiology, HBeAg, Horizontal transmission, Infectivity
Persistent URL dx.doi.org/10.1097/00042737-200511000-00004, hdl.handle.net/1765/62437
Journal European Journal of Gastroenterology and Hepatology
Eijck, A.A, Niesters, H.G.M, Hansen, B.E, Pas, S.D, Richardus, J.H, Mostert, M.C, … de Man, R.A. (2005). Paired, quantitative measurements of hepatitis B virus DNA in saliva, urine and serum of chronic hepatitis B patients. European Journal of Gastroenterology and Hepatology, 17(11), 1173–1179. doi:10.1097/00042737-200511000-00004