Risk to Cancer Patients From Nosocomial Hepatitis C Virus

Phylogenetic investigation of nosocomial transmission of hepatitis C virus in an oncology ward

Nosocomial hepatitis C virus (HCV) infections have been reported from different health-care settings worldwide. Twenty patients, treated at the same oncology department, with no previous record of hepatitis C infection, tested positive for anti-HCV antibodies between November 2007 and June 2008. Twelve of the newly infected patients were found to be HCV RNA positive. The common origin of the infections was assumed. To investigate the relatedness of the detected viral strains phylogenetic analyses were performed using sequences from the NS5B and E1/E2 genome regions. A patient carrying HCV for years was also involved in the study. She was treated at the same oncology department and was considered a possible infectious source. The previous HCV carrier harbored subtype 1b, while all other patients were infected with subtype 1a. Sequences from the 12 newly infected patients formed two groups. The viral sequences within the groups were very closely related. A greater evolutionary distance was observed between the two groups; however, their relatedness could be demonstrated by sequences from both regions with high statistical support. The results indicated that nosocomial transmission occurred. The phylogenetic analyses suggested that the viruses originated from a common source, possibly a patient carrying highly divergent variants. This presumed infectious source could not be identified in the course of this study. The genotype distribution of Hungarian control sequences included in the analysis confirmed this conclusion, since HCV genotype 1a was found to be relatively uncommon.

Health care-associated hepatitis B and C viruses: legal aspects

The risk of hepatitis B and C transmission in health care settings has generated considerable attention within the legal system. This article begins with an overview of the relevant sources of law and then explores legal duties and liability arising from two major categories of risk: occupational risks to health care providers and health care-associated risks to patients and other third parties.

Nosocomial infections in patients with cancer

Nosocomial infections are those that become evident 48 h or more after a patient is admitted for treatment in a hospital or in another health-care setting. These infections cause substantial morbidity and mortality in patients who are immunosuppressed. Over the past few decades, understanding of host vulnerability has improved and more rigorous management and infection-control practices have been adopted for treating susceptible populations. Despite efforts, outbreaks continue to occur. In this Review, we outline current knowledge of the incidence and microbiology of various nosocomial infections in patients with cancer-a large, immunosuppressed population.

Transmission of hepatitis C virus in an orthopedic hospital ward

Healthcare-associated infections with hepatitis C virus (HCV) hitherto have been observed mainly in hemodialysis settings as well as in hematology and oncology wards. In this communication, molecular and epidemiologic investigations to elucidate an HCV outbreak in an orthopedic ward are reported. One hundred and thirty-five patients hospitalized in the ward and 104 staff members were tested. In addition to extensive epidemiologic reviews and hygienic inspections, direct sequencing of HCV PCR fragments and phylogenetic analysis of more than 300 partial HCV sequences obtained by end-point limiting-dilution real-time PCR assay were carried out. Six patients were infected with very closely related HCV variants. Patient-to-patient spread of the virus was inferred to have started from one patient with previous HCV infection to the other five patients during their hospital stay. Inspections did not reveal substantial breaches in basic infection control practices and did not identify a specific activity that might have led to nosocomial transmission. As a result of the investigations, the hospital corrected the documentation of all medical and nursing activities undertaken in the ward, abandoned the use of all multidose saline and other medication vials, and included explicitly recommendations for the safe preparation and administration of injectable drugs into internal infection control guidelines. Thereafter, no further nosocomial transmissions of HCV have been recorded in the orthopedic ward. The events observed suggest that nosocomial transmission of HCV is not limited to hemodialysis, hematology or oncology settings, and they also reinforce the mandatory adherence to basic infection control practices.

Recent Canadian experience with targeted hepatitis C virus lookback

BACKGROUND

Targeted hepatitis C virus (HCV) lookback studies have been performed in Canada since 1995. The yield of HCV lookback has not been reassessed since the introduction of improved HCV screening tests.

STUDY DESIGN AND METHODS

Data were combined from the two Canadian blood suppliers to determine the yield of targeted HCV lookback performed on donors found to be HCV-positive by antibody screening and/or nucleic acid testing (NAT) from the introduction of NAT in 1999 until January 1, 2005.

RESULTS

Lookback was performed on 498 donations from 176 HCV-seropositive and two NAT-only-positive donors; 494 components had been transfused, and 160 components were traced to living recipients who underwent HCV testing. Seventy-two percent of recipients of components derived from donations given before the introduction of second-generation enzyme immunoassay (EIA) testing were HCV-seropositive. Four recipients of components derived from donations tested by second- or third-generation EIA, with or without NAT, were HCV-seropositive. Two of these recipients tested HCV-seropositive before transfusion, and a third was probably infected by transfusions before the introduction of HCV testing. The fourth recipient likely received a noninfectious transfusion, since five other recipients of components from subsequent donations made by this donor were seronegative.

CONCLUSION

When previous donations had been tested by second- or third-generation EIA, the yield of HCV lookback was likely zero. Because HCV infection is relatively common in the general population and patients in Canada do not undergo pretransfusion testing, coincident infections in recipients may be erroneously attributed to transfusion. The regulatory requirement for HCV lookback should be reassessed.