hepatitis c virus ( hcv ) infection is a common finding among haemodialysis populations worldwide . acute hcv infection significantly increases the risk of chronic hcv infection with a significant impact on the likelihood of progressive hepatic damage , hepatic failure and death . haemodialysis populations are at a heightened risk of acquiring and expressing hcv infection , and cross - infection between patients who undergo haemodialysis concurrently within centres has been well documented . several guideline bodies have advocated the use of standard infection control precautions to prevent nosocomial spread , and these practices have been shown to significantly reduce the risk of cross - infection between haemodialysis patients . transmission of hcv to sequential patients using the same haemodialysis machine , however , has not been widely reported , and thus , guideline groups do not advocate the use of dedicated haemodialysis machines for hcv - positive patients . we report a case where viral gene sequencing and phylogenetic analysis strongly suggest hcv transmission from a patient of low infectivity to a patient who shared the same haemodialysis machine . in this situation , no fault with the dialysis machine in question was recognized either at the time or subsequently . a 51-year - old woman with established renal failure due to diabetic nephropathy had been receiving regular haemodialysis three times per week at her regular outpatient haemodialysis unit for 7 years . a policy of routine three - monthly blood sampling for the presence of hepatitis b surface antigen and hepatitis c antibodies was in place , and this patient demonstrated consistently negative results throughout their time on renal replacement therapy . in early september 2009 , an hcv antibody titre for the patient was reported as equivocal. repeat testing 9 days later demonstrated an hcv antibody titre of 10.23 iu with a corresponding hcv polymerase chain reaction ( pcr ) titre of 8195 iu / ml ( 3.9 log copies ) . retrospective analysis of the preceding sample taken in june 2009 confirmed hcv pcr positivity and thus suggested acute infection . serum alanine transaminase titres were noted to be consistently < 30 iu / ml , while hepatitis a , hepatitis b , hiv and autoantibody screening were negative . she had never injected drugs nor undergone tattooing and had not received blood products during the 12 months prior to the first positive hcv pcr result . all patients who attended the same outpatient haemodialysis facility during the time of the possible transmission were hcv antibody negative . the index patient had however been admitted to a renal inpatient unit for a period of 10 days in late march / early april 2009 during treatment for an infected diabetic foot ulcer . at this time on one occasion , the patient underwent haemodialysis using a machine immediately following a known hcv - positive patient . consensus full - length e1e2 sequencing / phylogenetic analysis on samples from the recipient and suspected source , together with nine nottingham and eight glasgow epidemiologically unrelated genotype 3a control samples , were conducted . bootstrapped replicate trees for hepatitis c nucleic acid and amino acid sequencing ( figures 1 and 2 ) were generated for the suspected source , recipient , and the nine nottingham and eight glasgow hcv genotype 3a controls . these findings indicate infection with the same strain of virus . bootstrapped replicate trees for the hepatitis c nucleic acid sequencing demonstrated for the suspected source ( blue circles ) , suspected recipient ( red circles ) , and additional samples from nine nottingham ( black triangles ) and eight glasgow ( green triangles ) hcv 3a genotype controls . this shows a clustering of the source and recipient viruses being supported by 100% of the bootstrapped replicate trees . bootstrapped replicate trees for the hepatitis c amino acid sequencing demonstrated for the suspected source ( blue circles ) , suspected recipient ( red circles ) , and additional samples from nine nottingham ( black triangles ) and eight glasgow ( green triangles ) hcv 3a genotype controls . this shows a clustering of the source and recipient viruses being supported by 100% of bootstrapped replicate trees . the index case was known to be of low infectivity and dialysed at a different time from the affected patient . neither had ever undergone haemodialysis in the same facility at the same time . on the date of transmission , there was a time period of over 1 h between the index case leaving the unit and the recipient arriving with both patients supervised by different members of nursing staff . standard infection control policies were adhered to and were observed to be complied with . the haemodialysis machine in question had undergone a standard single cycle of chemical decontamination between patients and functioned without evidence of a fault . despite these practices , transmission of hcv via prevalence varies with geography and remains relatively high despite a decrease being demonstrated in european countries following the introduction of routine blood product screening in the early 1990s . prevalence estimates in the dialysis outcomes and practice patterns study ( dopps ) averaged 13.5% , although they varied from 2.6% to 22.9% between participating countries . horizontal cross - infection between haemodialysis patients can occur , predominately through direct environmental transmission of the virus . this is evidenced through the finding of higher rates of seroconversion in haemodialysis patients compared with peritoneal dialysis patients , increased seroconversion in those who were dialysed immediately adjacent to hcv - positive patients , and lower rates of seroconversion where physical isolation of the patients has occurred . hcv incidence has decreased in units where rigorous infection control policies targeting nosocomial spread have been applied . hcv outbreaks have also occurred where poor compliance with standard infection control measures has been found . these findings have translated into guideline bodies recommending that universal precautions to prevent nosocomial spread be applied . guideline bodies have , however , stopped short of recommending the use of dedicated machines to prevent sequential transmission of hcv . in this case , sequential hcv transmission seems to have occurred despite conforming to current guidance in practice . our local response to this case has been to ensure that all hcv - positive patients use dedicated haemodialysis machines that are not to be used in patients who are hcv negative . our standard infection control practices have remained in place , but we have not sought to isolate physically the hcv - positive population from the hcv - negative population within our units . we recommend that , in the light of this case , future blood - borne virus guidelines be extended to advocate the use of dedicated machines in the hcv - positive population .
hepatitis c virus ( hcv ) infection is a significant problem among haemodialysis populations worldwide . 
 horizontal cross - infection between patients can occur , predominately through direct environmental transmission of the virus . 
 current guidelines thus recommend universal barrier precautions , however they do not suggest using dedicated machines for hcv - positive patients to prevent the  sequential transmission of virus to those who subsequently use that machine . 
 we report a case where sequential hcv transmission occurred from a patient of low hcv infectivity with no identifiable machine fault . 
 we suggest that current guidelines should be reviewed to encourage the use of dedicated haemodialysis machines for hcv - positive patients .