Managing occupational risks for hepatitis C transmission in the health care setting

Hepatitis C virus (HCV) infection is a significant contemporary health problem in the United States and elsewhere. Because it is primarily transmitted via blood, hepatitis C infection presents risks for both nosocomial transmission to patients and occupational spread to health care workers. Recent insights into the pathogenesis, immunopathogenesis, natural history, and treatment of infection caused by this unique flavivirus provide a rationale for the use of new strategies for managing occupational hepatitis C infections when they occur. This article reviews this developing information. Recently published data demonstrate success rates in the treatment of "acute hepatitis C syndrome" that approach 100\%, and although these studies are not directly applicable to all occupational infections, they may provide important clues to optimal management strategies. In addition, the article delineates approaches to the prevention of occupational exposures and also addresses the difficult issue of managing HCV-infected health care providers. The article summarizes currently available data about the nosocomial epidemiology of HCV infection and the magnitude of risk and discusses several alternatives for managing exposure and infection. No evidence supports the use of immediate postexposure prophylaxis with immunoglobulin, immunomodulators, or antiviral agents. Based on the very limited data available, the watchful waiting and preemptive therapy strategies described in detail in this article represent reasonable interim approaches to the complex problem of managing occupational HCV infections, at least until more definitive data are obtained.

Estimation of the risk of bloodborne pathogens to health care workers after a needlestick injury in Taiwan

OBJECTIVES

To estimate the number of health care workers (HCWs) in Taiwan at risk annually for contracting hepatitis B virus (HBV), hepatitis C virus (HCV), and HIV after a needlestick and sharps injury (NSI) with a used hollow-bore needle.

METHODS

All patients hospitalized in 1 tertiary hospital between September 1997 and June 1998 had routine pathological work-ups. On the first day of the months of September 1997, December 1997, March 1998, and June 1998, 1805 samples of deidentified residual sera randomly sampled from 18,474 inpatients older than 6 years were serologically tested for antigens to HBV (HBsAg and HBeAg) and antibodies to HCV (anti-HCV) and HIV (anti-HIV) with enzyme-linked immunosorbent assay reagents. The frequency of NSIs with contaminated devices in HCWs from 16 public teaching hospitals between July 1996 and June 1997 and the serologic results were used to extrapolate the estimated annual rate of seroconversion in HCWs after an NSI.

RESULTS

Of the 1805 samples tested, 16.7% were seropositive for HBsAg (of which 1.7% were positive for HBeAg), 12.7% were positive for anti-HCV, and 0.8% were positive for anti-HIV. Of the 7550 NSIs reported by 8645 HCWs, 66.7% involved a contaminated hollow-bore needle. From these data, 308 to 924 HCWs were estimated to be at risk for contracting HBV; 334 to 836 were at risk for contracting HCV; and, at the most, 2 were at risk for contracting HIV. The estimated annual number of contaminated NSIs sustained by 4 categories of HCWs ranged from 0.3 to 0.7, resulting in 543 nurses, 113 technicians, 80 physicians, and 66 supporting staff to be at risk annually of acquiring HBV infection. The numbers of HCWs estimated to be at risk of acquiring HCV were 596 nurses, 90 physicians, 84 technicians, and 30 supporting staff. The risk of acquiring HIV was low, with 1 nurse and possibly 1 other staff potentially exposed annually.

CONCLUSIONS

Our estimates of the risk for seroconversion after an NSI have demonstrated that an occult risk can be formulated into a quantifiable risk. The number of susceptible HCWs at risk for seroconversion is as many as 1762 annually. With the number of nurses employed and the frequency with which they use sharps and sustain an NSI, 64.7% of all possible seroconversions will be in the nursing staff. This is a salient reminder of the importance of the introduction of early training in safe-needle-handling techniques before nurses enter their internship in countries where safety equipment, safety instructions, and staff vaccination programs are absent.

The risk of acquiring hepatitis B or C among public safety workers: a systematic review

CONTEXT

Determination of the occupational risk of hepatitis B and C to public safety workers is important in identifying prevention opportunities and has significant legal and policy implications.

OBJECTIVES

Characterize the risk of occupationally acquired infection: (1) risk of exposure to blood and body fluids, (2) seroprevalence of hepatitis B and C in the source population, and (3) risk of infection after exposure.

DATA SOURCES

Electronic search of MEDLINE (1991-1999), HealthStar (1982-1999), and CINAHL (1975-1999) supplemented by selected reference citations and correspondence with authors of relevant articles.

STUDY SELECTION

Peer-reviewed journal articles (N=702) that addressed the transmission of hepatitis B and C in law enforcement, correctional, fire, emergency medical services, and healthcare personnel were identified. One hundred five (15.0%) articles were selected for full-text retrieval; 72 (68.6%) were selected for inclusion.

DATA ABSTRACTION

Articles selected for inclusion were abstracted by two reviewers and checked by a third reviewer, using a standard reporting form.

DATA SYNTHESIS

Evidence tables were constructed, using the standardized abstracts. The tables were designed to summarize data for the key elements of the risk analysis.

CONCLUSIONS

Data suggest that emergency medical service (EMS) providers are at increased risk of contracting hepatitis B, but data have failed to show an increased prevalence of hepatitis C. EMS providers have exposure risks similar to those of hospital-based healthcare workers. Other public safety workers appear to have lower rates of exposure. Urban areas have much higher prevalence of disease, and public safety workers in those areas are likely to experience a higher incidence of exposure events.

Percutaneous injuries in anesthesia personnel

Anesthesia personnel are at risk for occupationally acquired blood-borne infections from human immunodeficiency virus, hepatitis viruses, and others after percutaneous exposures to infected blood or body fluids. The risk is greater after an infected, blood-contaminated, percutaneous injury, especially from a hollow-bore blood-filled needle, than from other types of exposures. Few data are available on the specific occupational hazards to anesthesia personnel from needles and other sharp devices. Fifty-eight percutaneous injuries (PIs) from anesthesia personnel in nine hospitals were analyzed. Thirty-nine of 58 PIs were from contaminated devices (all needles), and 19 were from uncontaminated devices or of unknown contamination status. Forty-three percent of contaminated percutaneous injuries (CPI) were classified as moderate (some bleeding) or severe (deep injury with profuse bleeding), and most were to health-care workers' hands. Fifty-nine percent of CPI were potentially preventable. Eighty-seven percent of CPI were from hollow-bore needles, and 68% of these were potentially preventable. The largest categories of devices causing CPI were needle on syringe, intravenous (i.v.) or arterial catheter needle-stylet, suture needle, and standard hollow-bore needle for secondary i.v. infusion. Most CPI occurred between steps of a multistep procedure (8%), were recapping related (13%), or occurred at other times after use (41%). No CPI were reported from use of needlestick-prevention safety devices. The devices and mechanisms of injury identified in this study provide specific data that may lead to prevention strategies to reduce the risk of PI.