Transmission of hepatitis B virus from an orthopedic surgeon with a high viral load.

BACKGROUND: During the evaluation of a needle-stick injury, an orthopedic surgeon was found to be unknowingly infected with hepatitis B virus (HBV) (viral load >17.9 million IU/mL). He had previously completed two 3-dose series of hepatitis B vaccine without achieving a protective level of surface antibody. We investigated whether any surgical patients had acquired HBV infection while under his care. METHODS: A retrospective cohort study of all patients who underwent surgery by the surgeon was conducted. Patients were notified of their potential exposure and need for testing, and samples with positive HBV loads underwent DNA sequencing. Characteristics of the surgical procedures for the cohort were evaluated. RESULTS: A total of 232 (70.7%) of potentially exposed patients consented to testing; 2 were found to have acute infection and 6 had possible transmission (evidence of past exposure without risk factors). Genome sequence analysis of HBV DNA from the infected surgeon and patients with acute infection revealed genetically related virus (>99.9% nucleotide identity). Only age was found to be statistically different between those with confirmed or possible HBV transmission and those who remained susceptible to HBV. CONCLUSIONS: We documented HBV transmission during orthopedic surgery to 2 patients from a surgeon with HBV. This investigation highlights the importance of evaluating individuals who do not respond to 2 series of HBV vaccination, the increased risk of HBV transmission from providers with high viral loads, and the need to evaluate the clinical practice of providers with HBV and implement appropriate procedure-based practice restrictions.

Health care-associated bloodstream infections associated with negative- or positive-pressure or displacement mechanical valve needleless connectors.

BACKGROUND: Health care-associated, central venous catheter-related bloodstream infections (HA-BSIs) are a major cause of morbidity and mortality. Needleless connectors (NCs) are an important component of the intravenous system. NCs initially were introduced to reduce health care worker needlestick injuries, yet some of these NCs may increase HA-BSI risk. METHODS: We compared HA-BSI rates on wards or intensive care units (ICUs) at 5 hospitals that had converted from split septum (SS) connectors or needles to mechanical valve needleless connectors (MV-NCs). The hospitals (16 ICUs, 1 entire hospital, and 1 oncology unit; 3 hospitals were located in the United States, and 2 were located in Australia) had conducted HA-BSI surveillance using Centers for Disease Control and Prevention definitions during use of both NCs. HA-BSI rates and prevention practices were compared during the pre-MV period, MV period, and post-MV period. RESULTS: The HA-BSI rate increased in all ICUs and wards when SS-NCs were replaced by MV-NCs. In the 16 ICUs, the HA-BSI rate increased significantly when SS-NCs or needles were replaced by MV-NCs (6.15 vs 9.49 BSIs per 1000 central venous catheter [CVC]-days; relative risk, 1.54; 95% confidence interval, 1.37-1.74; P < .001). The 14 ICUs that switched back to SS-NCs had significant reductions in their BSI rates (9.49 vs 5.77 BSIs per 1000 CVC-days; relative risk, 1.65; 95% confidence interval, 1.38-1.96; p < .001). BSI infection prevention strategies were similar in the pre-MV and MV periods. CONCLUSIONS: We found strong evidence that MV-NCs were associated with increased HA-BSI rates, despite similar BSI surveillance, definitions, and prevention strategies. Hospital personnel should monitor their HA-BSI rates and, if they are elevated, examine the role of newer technologies, such as MV-NCs.

Influenza in the acute hospital setting.

Influenza poses special hazards inside healthcare facilities and can cause explosive outbreaks of illness. Healthcare workers are at risk of acquiring influenza and thus serve as an important reservoir for patients under their care. Annual influenza immunisation of high-risk persons and their contacts, including healthcare workers, is the primary means of preventing nosocomial influenza. Despite influenza vaccine effectiveness, it is substantially underused by healthcare providers. Influenza can be diagnosed by culturing the virus from respiratory secretions and by rapid antigen detection kits; recognition of a nosocomial outbreak is important in order to employ infection-control efforts. Optimal control of influenza in the acute-care setting should focus upon reducing potential influenza reservoirs in the hospital, including: isolating patients with suspected or documented influenza, sending home healthcare providers or staff who exhibit typical symptoms of influenza, and discouraging persons with febrile respiratory illness from visiting the hospital during a known influenza outbreak in the community. (Note: influenza and other respiratory viruses can cause non-febrile illness but are still transmissible.) The antiviral M2 protein inhibitors (amantadine, rimantadine) and neuraminidase inhibitors (zanamivir, oseltamivir) have proven efficacy in treating and preventing influenza illness; however, their role in the prevention and control of influenza in the acute hospital setting remains to be more fully studied.

Ultraviolet light disinfection of hospital water for preventing nosocomial Legionella infection: a 13-year follow-up.

BACKGROUND AND OBJECTIVE: CDC has estimated that 23% of Legionella infections are nosocomial. When a new hospital was being constructed and a substantial increase in transplantation was anticipated, an ultraviolet light apparatus was installed in the water main of the new building because 27% of water samples from taps in the old hospital contained Legionella. This study reports the rate of nosocomial Legionella infection and water contamination since opening the new hospital. METHODS: Charts of all patients with positive Legionella cultures, direct immunofluorescent antibody (DFA), or urine antigen between April 1989 and November 2001 were reviewed. Frequencies of DFAs and urine antigens were obtained from the laboratory. RESULTS: None of the 930 cultures of hospital water have been positive since moving into the new building. Fifty-three (0.02%) of 219,521 patients had a positive Legionella test; 41 had pneumonia (40 community acquired). One definite L. pneumophila pneumonia confirmed by culture and DFA in August 1994 was nosocomial (0.0005%) by dates. This patient was transferred after prolonged hospitalization in another country, was transplanted 11 days after admission, and developed symptoms 5 days after liver transplant. However, tap water from the patient's room did not grow Legionella. Seventeen (2.5%) of 670 urine antigens were positive for Legionella (none nosocomial). Thirty-three (1.2%) of 2,671 DFAs were positive, including 7 patients (21%) without evidence of pneumonia and 6 (18%) who had an alternative diagnosis. CONCLUSION: Ultraviolet light usage was associated with negative water cultures and lack of clearly documented nosocomial Legionella infection for 13 years at this hospital.

Evaluation and treatment of acute bronchitis at an academic teaching clinic.

BACKGROUND: Randomized controlled trials have demonstrated that antibiotics provide no benefit for acute bronchitis, yet 55 to 90% of patients who receive this diagnosis are treated with antibiotics. Given substantial data against antibiotics for acute bronchitis, it could be expected that physicians at academic teaching institutions would be less likely to prescribe antibiotics. However, limited data of antibiotic use for acute bronchitis in this setting has been published. METHODS: Charts of patients seen between January 1 and October 25, 2000, who received an ICD-9 diagnosis of acute bronchitis or upper respiratory infection (URI) at the University of Virginia internal medicine clinic were reviewed. Patients were excluded if they had no cough, chronic obstructive pulmonary disease, symptoms for > or = 3 weeks, or antibiotics for another reason. RESULTS: Of the 160 patients included in this study, 105 (66%) received an antibiotic. Multivariate analysis revealed that patients with increasing age (P = 0.002), purulent cough (P = 0.003), abnormal exam (P = 0.003), and comorbidities (P = 0.03) were most likely to receive an antibiotic. Smoking, duration of symptoms, gender, and race did not predict antibiotic use (P > 0.05). Macrolides accounted for 68% of antibiotics. Twenty-two (14%) of all patients received a chest radiograph and 72 (45%) received an inhaler. Of those who had chest radiographs negative for signs of infection, 76% received an antibiotic. CONCLUSION: In our teaching clinic, antibiotics were overused, whereas chest radiographs and inhalers were underused for the evaluation and treatment of acute bronchitis. Recently published guidelines will help curb use of antibiotics, but a more intensive intervention, including physician and patient education is probably necessary.

Updated review of blood culture contamination.

Blood culture contamination represents an ongoing source of frustration for clinicians and microbiologists alike. Ambiguous culture results often lead to diagnostic uncertainty in clinical management and are associated with increased health care costs due to unnecessary treatment and testing. A variety of strategies have been investigated and employed to decrease contamination rates. In addition, numerous approaches to increase our ability to distinguish between clinically significant bacteremia and contamination have been explored. In recent years, there has been an increase in the application of computer-based tools to support infection control activities as well as provide clinical decision support related to the management of infectious diseases. Finally, new approaches for estimating bacteremia risk which have the potential to decrease unnecessary blood culture utilization have been developed and evaluated. In this review, we provide an overview of blood culture contamination and describe the potential utility of a variety of approaches to improve both detection and prevention. While it is clear that progress is being made, fundamental challenges remain.