Originalia R Fabris, D. Infantolino, M. R. Biasin, G. Marchelle, E. Venza, V. Terribile Wiel Marin, R Benedetti, G. Tositti, V. Manfrin, E de Lalla High Prevalence of HCV-RNA in the Saliva Cell Fraction of Patients with Chronic Hepatitis C But No Evidence of HCV Transmission among Sexual Partners Summary: The aims of this study were to evaluate the prevalence of HCV-RNA in differ- ent fractions of saliva taken from patients with chronic hepatitis C, to establish whether vir- ologic parameters or disease severity exert any influence on the detectability of HCV-RNA in saliva, and to evaluate the prevalence of HCV infection in partners of HCV-infected sub- jeers with respect to the presence of HCV-RNA in saliva. Sera samples and different frac- tions of saliva (whole saliva, surnatant, and cell fraction) from 48 subjects (45 with chronic hepatitis C and three healthy anti-HCV+ carriers) were examined for HCV-RNA by RT nested PCR and DEIA hybridization. HCV-RNA-positive sera were also tested for geno- type and viral titer (bDNA2 method). Twenty-seven stable sexual partners (25 females and 2 males) were screened for anti-HCV antibodies at least twice over a minimum of 12 months. HCV-RNA was detected in the sera of 39/45 patients and of 22/39 viremic patients. In all of the latter, the presence of HCV-RNA was restricted to the cell fraction. Viral titer was significantly hi]~her in patients with HCV-RNA in saliva than in those without (12.3 • 106 versus 4.6 • 10~ P<0.01). HCV-RNA positivity was unrelated to genotype, dura- tion of disease, Hepatitis Activity Index scores or transaminase levels. Anti-HCV was pos- itive in one of 13 sexual partners of patients with HCV-RNA in saliva and in 1/14 of those without (P = NS). In conclusion, HCV-RNA is detectable in the cell fraction of saliva in a high proportion of highly viremic patients with chronic hepatitis C, but its presence does not seem to be associated with an increased risk of HCV transmission among sexual part- ners. Introduction The main risk factors for the transmission of HCV are known to be the transfusion of blood and its derivates, intravenous drug use. and injuries with contaminated nee- dles, whereas sexual and vertical transmission appear to play a minimal role [1-4]. However, a relatively high pro- portion of HCVoinfected subjects exhibits no identifiable major risk factors, thus suggesting the possibility of other transmission routes [1, 5, 6]. Following the demonstration that HCV infection can be transmitted to the chimpanzee through saliva inoculation [71 and the report of one case of transmission by a human bite [8], the prevalence of HCV-RNA in saliva has been extensively studied to eval- uate the capacity of saliva to serve as a source of HCV infection. The results of these studies document a high variability of positivity which might be related to variable criteria of recruitment, to different methods for saliva testing and to the analysis of different saliva fractions, therefore hampering the assessment of whether the detectability of HCV-RNA in saliva depends on the serum viral titer, genotype, or severity of liver disease [9, 10]. Moreover, few data are available on the prevalence of HCV infection in partners of subjects displaying positive HCV-RNA in saliva. Hence, the capacity of saliva to func- tion as a vehicle of HCV transmission remains controver- sial. The aims of this study were to evaluate the preva- lence of HCV-RNA in different fractions of saliva taken from patients with chronic hepatitis C, to establish wheth- er HCV-RNA positivity in serum, genotype, viral load, or disease severity exert any influence on the detectability of HCV-RNA in saliva, and to evaluate the prevalence of HCV infection in the partners of HCV-infected subjects with reference to HCV-RNA positivity in saliva. Patients and Methods Forty-five subjects (42 men and three women; age range=2(P453, mean 33.2) with chronic hepatitis C were recruited amongst patients referred to our unit for liver bioptic testing over 2 years (January 1996 - December 1997); three healthy anti-HCV car- riers (i.e., subjects displaying normal ALT levels for more than 2 years) were also enrolled. All subjects exhibited a positive anti- HCV screening test (Ortho Diagnostic Systems, Raritan, NJ, USA) and had been confirmed by RIBA 11, but were negative for both HBsAg and HIV testing; none had dcclared habitual alcoholic abuse. Patients with chronic hepatitis exhibited raised Received: 5 October 1998/Accepted: 18 January 1999 P. Fabris, M. D., P. Benedetti, M. D., Giulia Tositti, M. D., V. Manfrin, M. D., F. de Lalla, M. D., Dept. of Infectious Diseases, Ospedale S. Bortolo, Vialc Rodolfi, 1-36100 Vicenza; D. Infantolino, Ph.D., Maria Raffaella Biasin, Ph.D., Giuditta Marchelle, Tech., E. Venza, M. D., Dept. of Pathology, Montebelluna and Castelfranco Veneto Hospitals; V. Terribile Wiel Marin, M. D., Chair of Pathology, School of Odontostomatology, University of Padova, Italy. 12 / 86 Infection 27 (1999) No. 2 9MMV Medien & Medizin VerlagsGmbH Mtinchen 1999