Background: An ongoing HCV epidemic currently affects a growing proportion of HIV‐positive men who have sex with men (MSM) in Europe. Recently in the North‐Rhine region of Germany, we have observed an increase in acute HCV infections of genotype 4 (HCV‐4).
Aims: To characterize the current spread of HCV‐4 among German MSM using a molecular epidemiological approach.
Methods: Patient characteristics and sera were collected for HIV‐positive MSM diagnosed with acute HCV‐4 infections in the North‐Rhine region (n=14), Hamburg (n=14), Frankfurt (n=4) and Berlin (n=4). Part of the HCV NS5B region (436 bp) was amplified, sequenced and compared with HCV‐4 sequences from HIV‐positive Dutch, English and French MSM (n=50) as well as unrelated HCV risk groups (n=61).
Results: NS5B sequences were obtained from 35/36 (97%) of German cases, all of which were HCV subtype 4d (HCV‐4d). The phylogenetic analysis of HCV sequences revealed two MSM‐specific HCV‐4d clusters of 71 and 12 sequences. All except one of the German MSM belonged to a large MSM‐specific HCV cluster containing MSM from all four different European countries. None of the HCV‐4 strains circulating among injecting drug users or in HCV‐4 endemic areas were part of the MSM‐specific clusters.
Conclusions: HCV rapidly spreads among European HIV‐positive MSM through a joint international transmission network, separate from that of injecting drug users. In order to contain this epidemic, non‐parenteral routes of transmission, such as unsafe sex, must be taken into consideration and prevention measures should be refocused accordingly.