Features of HCV That Favor Transmission in Dialysis Centers

Several features of HCV enhance the risk of transmission in hemodialysis centers: (1) HCV infection is common in the United States. (2) HCV is transmissible via needle sticks and other parenteral exposures. (3) HCV is stable in the environment for days to weeks. (4) Most patients with HCV are asymptomatic. The CDC estimates that there are 2.7 million persons with chronic HCV infection in the United States. ² Transmission routes for HCV include infection drug use, needle-stick injuries in healthcare, sharing personal items contaminated with infectious blood (eg, razors), and other healthcare procedures that involve invasive procedures such as injections. The risk of transmission via a parenteral exposure such as a needle stick is between 1% and 2%.Reference Pozzetto, Memmi, Garraud, Roblin and Berthelot ³ A meta-analysis reported the rate or transmission by needle sticks as 1.9%.Reference Henderson ⁴ Various studies have reported that HCV inoculated onto surfaces survived at room temperature for up to 16 hours,Reference Kamili, Krawczynski, McCaustland, Li and Alter ⁵ up to 5 days,Reference Doerrbecker, Friesland and Ciesek ⁶ and up to 6 weeks.Reference Paintsil, Binka, Patel, Lindenbach and Heimer ⁷ HCV survived in tuberculin syringes for up to 63 days.Reference Paintsil, He, Peters, Lindenbach and Heimer ⁸ Importantly, ~70%–80% of patients with HCV are asymptomatic. ^{2 ,} Reference Pozzetto, Memmi, Garraud, Roblin and Berthelot ³ Thus, infection can only be detected via diagnostic tests. Failure to obtain HCV testing to identify infected persons may lead to decreased attention to infection control in infected persons.

Characteristics of Dialysis Centers that Enhance the Possibility of HCV Transmission

A number of characteristics of hemodialysis centers and the process of dialysis enhance the possibility of HCV transmission. (1) Patients are generally placed in bays separated from other patients by a short distance. (2) Sinks may not be available in each bay. (3) HCP have frequent contact with blood-containing devices. (4) Facilities may lack separate clean and dirty utility rooms or a separate medication preparation area. (5) Dialysis centers are usually free standing and do not have immediate access to trained infection control preventionists. (6) Dialysis machines and equipment are heavily blood contaminated and must be disinfected with strict adherence to manufacturer’s recommendations and sterilization/disinfection guidelines.

Patient Characteristics That Promote Transmission of HCV

Several patient characteristics promote transmission of HCV: (1) Dialysis is prolonged and patients require venous access. (2) Patients frequently receive medications via injection or infusion. (3) Patients may be unable to fully participate in their care.

Infection Control in Hemodialysis Centers

Multiple studies have demonstrated that HCP in dialysis centers are often poorly compliant with infection guidelines to prevent HCV transmission in these settings.Reference Shimokura, Weber, Miller, Wurtzel and Alter ^{9 ,} Reference Shimokura, Chai and Weber ¹⁰ Shimokura et alReference Shimokura, Weber, Miller, Wurtzel and Alter ⁹ used a cluster random survey design to study HCP in 53 hemodialysis facilities in the United States in 2000. Only 57% of these facilities reported that HCP always performed hand hygiene (HH) and changed gloves before putting patients on dialysis; 47% reported that HCP performed HH between patient care stations; and 55% reported that HCP performed HH between patients when administering intravenous medications,Reference Shimokura, Weber, Miller, Wurtzel and Alter ⁹ In a more detailed analysis, Shimokura et alReference Shimokura, Chai and Weber ¹⁰ reported that the patient care practices independently associated with a higher center prevalence of HCV included reusing priming receptacles without disinfection (odds ratio [OR], 2.3), handling blood specimens adjacent to medications and clean supplies (OR, 2.2), and using mobile carts to deliver injectable medications (OR, 1.7). Independently related facility covariates were ≥10% patient HCV prevalence (OR, 3.0), patient-to-staff ratio >7 to 1 (OR, 2.4), and treatment duration ≥2 years (OR, 2.4).

Lessons from Outbreaks of HCV in Hemodialysis Centers

Outbreaks of HCV in hemodialysis centers continue to be reported (Table 1).Reference Savey, Simon, Izopet, Lepoutre, Fabry and Desenclos ^{11 –} Reference Aho, Giraudon and Astruc ²⁰ The papers in this issue by Nguyen et alReference Nguyen, Gutowski and Ghiselli ¹⁹ and Aho et alReference Aho, Giraudon and Astruc ²⁰ add to the growing body of knowledge regarding the breaches in infection control practices that lead to HCV outbreaks. Most clusters of HCV were associated with multiple breaches in infection control practices. The potential breaches described in these outbreaks demonstrate the following common themes: (1) use of multidose vials generally for heparin or saline administration; (2) poor compliance with hand hygiene before and after each patient contact or after touching a possibly contaminated surface; (3) failure to change gloves when moving between patients or between patients and potentially contaminated surfaces; (4) failure to adequately disinfect environmental surfaces; (5) unsafe injection practices; (6) failure to disinfect shared equipment between patient uses; (6) lack of a separate area for medication preparation; and (7) failure to have clearly separated clean and dirty utility rooms. Reviews of outbreak investigations between 1998 and 2008 revealed similar deficiencies in infection control practices.Reference Patel, Thompson, Kallen and Arduino ²¹

Table 1

Selected Recent Clusters of Hepatitis C Virus in Hemodialysis Centers, 2005–2015

NOTE. HCP, healthcare provider; HCV, hepatitis C virus; HH, hand hygiene.

^a Cases may have been distributed among multiple clusters as identified by molecular analysis; not all patients identified may have been linked to the outbreak(s).

These outbreaks also demonstrate the importance of using molecular methods in outbreak investigations of HCV outbreaks related to dialysis. In many cases, multiple small clusters were demonstrated rather than a single large clonal cluster.

Preventing HCV Transmission during Dialysis

Detailed recommendations are available from the CDC for preventing the transmission of infections among chronic hemodialysis patients; ²² they have been updated by the CDC to clarify guidance on parenteral medical vial. ²³ Strict adherence to these guidelines should prevent person-to-person transmission of HCV in hemodialysis centers. Furthermore, recent advances in therapy for hepatitis C have demonstrated that direct acting antiviral regimens are safe and highly effective for treating HCV-infected patients on hemodialysis.Reference Roth, Nelson and Bruchfeld ²⁴ Thus, screening and identification of HCV in hemodialysis patients with consideration for treatment could further decrease the risk of transmission within dialysis units.