A systematic virological follow-up of 114 haemodialysis patients treat
ed in the same unit showed that 37, including 17 PCR positive patients
, were seropositive for hepatitis C virus (HCV). Type Ib HCV was detec
ted in 10 patients and was much more frequent in this population than
in the whole population of patients treated in the hepatogastroenterol
ogy departments in southeastern France. The E1/E2 genomic region of se
ven type Ib HCV strains was sequenced. In four patients, a similar str
ain was detected in both the Fl variable region and the E2 hypervariab
le region (HVR1). In addition, two of these four patients were seroneg
ative and PCR negative at the beginning of the study and had not been
transfused or transplanted during this period. A phylogenetic tree was
drawn which confirmed that these strains were very similar and showed
that HCV was transmitted via the nosocomial pathway in this haemodial
ysis unit. (C) 1996 Wiley-Liss, Inc.