Sampling for collection of central line-day denominators in surveillance of healthcare-associated bloodstream infections.

OBJECTIVE: To determine the feasibility of estimating the number of central line-days at a hospital from a sample of months or individual days in a year, for surveillance of healthcare-associated bloodstream infections. DESIGN: We used data reported to the National Nosocomial Infections Surveillance system in the adult and pediatric intensive care unit component for 1995-2003 and data from a sample of hospitals' daily counts of device use for 12 consecutive months. We calculated the percentile error as the central line-associated bloodstream infection percentile based on rates per line-days minus the percentile based on rates per estimated line-days. SETTING AND PARTICIPANTS: A total of 247 hospitals were used for sampling whole months and 12 hospitals were used for sampling individual days. RESULTS: For a 1-month sample of central line-days data, the median percentile error was 3.3 (75th percentile, 7.9; 90th percentile, 15.4). The percentile error decreased with an increase in the number of months sampled. For a 3-month sample, the median percentile error was 1.4 (75th percentile, 4.3; 95th percentile, 8.3). Sampling individual days throughout the year yielded lower percentile errors than sampling an equivalent fraction of whole months. With 1 weekday sampled per week, the median percentile error ranged from 0.65 to 1.40, and the 90th percentile ranged from 2.8 to 5.0. Thus, for 90% of units, collecting data on line-days once a week provides an estimate within +/-5 percentile points of the true line-day rate. CONCLUSION: Sample-based estimates of central line-days can yield results that are acceptable for surveillance of healthcare-associated bloodstream infections.

Protective effect of hepatitis B vaccine in chronic hemodialysis patients.

Hepatitis B virus (HBV) infection is a well-recognized risk in chronic hemodialysis patients. Although the risk has declined dramatically since the 1970s, outbreaks of HBV infection among these patients continue to occur. The Centers for Disease Control and Prevention (CDC) has recommended hepatitis B vaccination of hemodialysis patients since 1982; however, by 1996, only 36% of the approximately 200,000 US chronic hemodialysis patients had received the vaccine, perhaps in part because of doubts among dialysis personnel of its efficacy. We performed a case-control study to determine whether receipt of hepatitis B vaccine was associated with a decreased risk of acquiring HBV infection. We determined the vaccination status of all chronic hemodialysis patients at 98 US hemodialysis centers that reported patients with acute HBV infection on a nationwide mailed survey in 1995. A total of 111 hepatitis B surface antigen (HBsAg) positive case patients were compared with 12,500 control patients. Case patients were significantly less likely than control patients to have received hepatitis B vaccine (10.8% v 23.6%; odds ratio, 0.39; 95% confidence interval, 0.22-0.72). After stratifying by dialysis center to control for differing community and dialysis center risks of HBV infection, we found that the risk for HBV infection was 70% lower in vaccinated patients (adjusted odds ratio, 0.30; 95% confidence interval, 0.18-0.50). These results suggest that hepatitis B vaccine has a significant protective effect against acquiring HBV infection in chronic hemodialysis patients, and efforts should be expanded to increase the use of hepatitis B vaccine in this patient population.

A prospective study of vascular access infections at seven outpatient hemodialysis centers.

Vascular access infections are a major cause of morbidity and mortality in hemodialysis patients, and the use of antimicrobials to treat such infections contributes to the emergence and spread of antimicrobial-resistant bacteria. To determine the incidence of and risk factors for vascular access infections, we studied hemodialysis patients at 7 outpatient dialysis centers (4 in Richmond, VA, and 3 in Baltimore, MD) during December 1997 to July 1998. Vascular access infections were defined as local signs (pus or redness) at the vascular access site or a positive blood culture with no known source other than the vascular access; and hospitalization or receipt of an intravenous (IV) antimicrobial. A total of 796 patients were followed for 4,134 patient-months. The vascular access infection rate was 3.5/100 patient-months, ie, patients had a 3.5% risk of infection each month. Independent risk factors were the specific dialysis unit where the patient was treated (relative hazard varying from 1.0 to 4.1 among the 7 centers), catheter access (relative hazard, 2.1 v implanted access), albumin level (relative hazard, 2.4 for lowest v highest quartile), urea reduction ratio (relative hazard, 2.2 for lowest v highest quartile), and hospitalizations during the previous 90 days (relative hazard, 4.9 for >/=6 v zero hospitalizations). These data confirm that vascular access infections are common in hemodialysis patients and that infection rates differ substantially among different centers. Catheter use should be minimized to reduce these infections. Additionally, the possibility that improved serum albumin and urea reduction ratio could reduce vascular access infections should be evaluated.

Modifiable risk factors associated with deep sternal site infection after coronary artery bypass grafting.

OBJECTIVE: Our objective was to identify risk factors for deep sternal site infection after coronary artery bypass grafting at a community hospital. METHODS: We compared the prevalence of deep sternal site infection among patients having coronary artery bypass grafting during the study (January 1995-March 1998) and pre-study (January 1992-December 1994) periods. We compared any patient having a deep sternal site infection after coronary artery bypass graft surgery during the study period (case-patients) with randomly selected patients who had coronary artery bypass graft surgery but no deep sternal site infection during the same period (control-patients). RESULTS: Deep sternal site infections were significantly more common during the study than during the pre-study period (30/1796 [1.7%] vs 9/1232 [0.7%]; P =.04). Among 30 case-patients, 29 (97%) returned to the operating room for sternal debridement or rewiring, and 2 (7%) died. In multivariable analyses, cefuroxime receipt 2 hours or more before incision (odds ratio = 5.0), diabetes mellitus with a preoperative blood glucose level of 200 mg/dL or more (odds ratio = 10.2), and staple use for skin closure (odds ratio = 4.0) were independent risk factors for deep sternal site infection. Staple use was a risk factor only for patients with a normal body mass index. CONCLUSIONS: Appropriate timing of antimicrobial prophylaxis, control of preoperative blood glucose levels, and avoidance of staple use in patients with a normal body mass index should prevent deep sternal site infection after coronary artery bypass graft operations.

The cost of selected tuberculosis control measures at hospitals with a history of Mycobacterium tuberculosis outbreaks.

OBJECTIVE: To determine the cost of nonrespirator-related tuberculosis (TB) control measures at several hospitals, following publication of the Centers for Disease Control and Prevention (CDC)'s revised TB infection control guidelines. DESIGN: Infection control (IC) and TB coordinators obtained cost information on tuberculin skin-test (TST) programs, addition of IC and employee health service (EHS) personnel, and the retrofit or new construction of environmental controls. SETTING: Four hospitals with, and one community hospital without, prior nosocomial multidrug-resistant TB transmission. RESULTS: During the study period, the TST program costs remained constant at four of five hospitals and increased at one hospital (median 1994 TST program cost: $5,568; range, $2,393-$44,902). Additional IC or EHS personnel were hired at four of five hospitals (median cost increase, $125,500; range, $63,000-$228,000). The median cost of new construction or new equipment purchases (ie, sputum induction booths, ultraviolet lights, or portable high-efficiency particulate air filters) at study hospitals was $163,000 (range, $45,000-$524,000) and $70,000 (range, $31,000-$93,000), respectively. CONCLUSIONS: Costs associated with implementing control measures similar to those recommended in the CDC TB IC guidelines varied widely by hospital. Engineering controls involved the largest capital outlay, but increases in personnel were the largest continuing cost. These costs represent improvements made to upgrade selected aspects of hospital TB control programs, not the cost of an optimal TB control program.

The costs of healthcare worker respiratory protection and fit-testing programs.

OBJECTIVE: We studied hospital costs associated with healthcare worker (HCW) respiratory protection and respirator fit-testing programs recommended by the Centers for Disease Control and Prevention (CDC) and mandated by the Occupational Safety and Health Administration to decrease nosocomial or occupational Mycobacterium tuberculosis (TB). DESIGN: The number and cost of high-efficiency particulate air (HEPA)-filter and dust-mist (DM) respirators for 1989 to 1994 were obtained from study hospital purchasing departments, and the costs of HCW fit-testing and education programs for 1994 were estimated from information provided by infection control practitioners. Costs of N-class respirator programs were estimated for study hospitals using retrospective cost analysis and an observational study. SETTING: Four urban hospitals with, and one rural community hospital without, documented nosocomial or occupational transmission of multidrug-resistant TB. RESULTS: During the study period, four of five hospitals introduced HEPA and DM respirators and respirator education and fit-testing programs. Median costs in 1994 were $83,900 (range, $2,000-$223,000) for respirators and $17,187 (range, $8,736-$26,175) for respiratory fit-testing programs. The projected median annual cost of N95 respirators was $62,023 (range, $270-$422,526). CONCLUSIONS: Compliance with CDC TB guidelines may require a substantial investment. However, outlays for respirators and education and fit-testing programs are more reasonable than would be suggested by analyses that estimated the costs of preventing one case of nosocomial TB.

Tuberculosis in hemodialysis patients in New Jersey: a statewide study.

OBJECTIVE: To study the incidence of tuberculosis (TB), tuberculin skin testing (TST) practices, and infection control practices at outpatient hemodialysis centers. DESIGN: Mail surveys performed in December 1994 and 1995. MAIN OUTCOME MEASURES: The numbers of patients with incident active TB during 1994 and 1995, TST policies during 1994, and TB infection control policies in 1994. SETTING: All outpatient dialysis centers in New Jersey. PATIENTS OR PARTICIPANTS: Healthcare workers and patients in dialysis centers in New Jersey. RESULTS: Of 47 centers, 41 provided information on TST and TB infection control policies and practices. TSTs were performed on newly hired healthcare workers at all 41 centers and on established workers at 39 centers. In contrast, only 1 center reported performing TSTs on hemodialysis patients; 5 other centers reported screening of patients for TB using chest radiographs. Active TB was reported in 3 of 4,550 chronic hemodialysis patients in 1994 (rate, 66/100,000 patient-years) and in 4 of 4,831 patients in 1995 (rate, 83/100,000 patient-years). Both rates were several times higher than the rate in the New Jersey general population during this period (10.7-10.8/100,000). CONCLUSION: Although based on small numbers of patients with TB, we found a relatively high incidence of TB among hemodialysis patients in New Jersey. Most centers reported performing TSTs on workers but not on patients. These results suggest the need for improved TB screening and infection control precautions at outpatient dialysis centers.

Outbreak of Pseudomonas aeruginosa ventriculitis among patients in a neurosurgical intensive care unit.

OBJECTIVE: To determine the cause of an outbreak of Pseudomonas aeruginosa cerebral ventriculitis among eight patients at a community hospital neurosurgical intensive care unit. All had percutaneous external ventricular catheters (EVCs) to monitor cerebrospinal fluid (CSF) pressure. METHODS: Cohort study of all patients who had EVCs placed during the epidemic period (August 8-October 22, 1997). A case-patient was any patient with P aeruginosa ventriculitis during the epidemic period. Pulsed-field gel electrophoresis (PFGE) was performed on all isolates. RESULTS: P aeruginosa was significantly more likely to be isolated from CSF per EVC placed in the epidemic than pre-epidemic (January 1-August 7, 1997) periods (8/61 [13%] vs 2/131 [1.5%], P=.002). During the epidemic period, ventriculitis was significantly more likely after EVC placement in the operating room than in other units (8/24 vs 0/22, P=.004). EVC placement technique differed for EVCs placed in the operating room (little hair was removed, preventing application of an occlusive dressing) versus other hospital units (more hair was removed, and an occlusive dressing was applied). Among patients who had operating room EVC placement, contact with one healthcare worker was statistically significant (7/13 vs 0/8, P=.02). Hand cultures of this worker were negative. All isolates had closely related PFGE patterns. CONCLUSIONS: These data suggest that a single healthcare worker may have contaminated EVC insertion sites, resulting in an outbreak of P aeruginosa ventriculitis. Affected patients were unlikely to have had an occlusive dressing at the EVC insertion site. Application of a sterile occlusive dressing may decrease the risk of ventriculitis in patients with EVCs.

Bacterial contamination of platelets at a university hospital: increased identification due to intensified surveillance.

BACKGROUND: A cluster of bacterial contamination of platelets occurred at a university hospital in a one-month period. This unusual clustering allowed us to examine the likely mechanism of contamination and clinical sequelae. METHODS: We reviewed medical records of patients receiving random donor platelet transfusions to determine numbers of platelets transfused, reactions reported, and episodes of bacterial contamination. We also reviewed procedures at the collecting blood agencies and the hospital blood bank. RESULTS: Four patients received bacterially contaminated platelets during June and July 1991. The rates of reported platelet transfusion reactions increased significantly (P < 0.001) from September 1989 through July 1991 (study period); in addition, the rate of contamination of platelets during June and July 1991 was 23-fold higher than during the previous 21 months (P < 0.001). Surveillance methodology changed dramatically during the study period, contributing to the recognition of the current cluster. Pathogens isolated from the contaminated platelet pools were Bacillus cereus, Staphylococcus epidermidis, or Pseudomonas aeruginosa in titers ranging from 10(6) to 10(8) colony forming units/mL. Four constituent individual platelet units identified as the probable cause of the outbreak (including one postepidemic episode) were significantly older (mean age, 4.8 days) than 106 randomly selected individual platelet units (mean age, 3.7 days; P = 0.04). Platelet pools were transfused an average of 2.5 hours after pooling. Review of blood collection and platelet preparation practices did not identify breaks in procedure or technique that could have caused contamination. CONCLUSIONS: Increased awareness of platelet transfusion reactions by clinical staff and routine culturing of all platelets associated with transfusion reactions will identify contaminated platelets. Identification of contaminated platelets is necessary to treat affected patients appropriately and to determine the prevalence of and risk factors for contaminated platelets (Infect Control Hosp Epidemiol 1994;15:82-87).

Evaluation of infection control measures in preventing the nosocomial transmission of multidrug-resistant Mycobacterium tuberculosis in a New York City hospital.

OBJECTIVE: To evaluate the efficacy of Centers for Disease Control and Prevention (CDC)-recommended infection control measures implemented in response to an outbreak of multidrug-resistant (MDR) tuberculosis (TB). DESIGN: Retrospective cohort studies of acquired immunodeficiency syndrome (AIDS) patients and healthcare workers. The study period (January 1989 through September 1992) was divided into period I, before changes in infection control; period II, after aggressive use of administrative controls (eg, rapid placement of TB patients or suspected TB patients in single-patient rooms); and period III, while engineering changes were made (eg, improving ventilation in TB isolation rooms). SETTING: A New York City hospital that was the site of one of the first reported outbreaks of MDR-TB among AIDS patients in the United States. PARTICIPANTS: All AIDS patients admitted during periods I and II. Healthcare workers on nine inpatient units with TB patients and six without TB patients. RESULTS: The epidemic (38 patients) waned during period II and only one MDR-TB patient presented during period III. The MDR-TB attack rate among AIDS patients hospitalized on the same ward on the same days as an infectious MDR-TB patient was 8.8% (19 of 216) during period I, decreasing to 2.6% (5 of 193; P = 0.01) during period II. In a small group of healthcare workers with tuberculin skin test data, conversions during periods II through III were higher on wards with than without TB patients (5 of 29 versus 0 of 15; P = 0.15), although the difference was not statistically significant. CONCLUSIONS: Transmission of MDR-TB among AIDS patients decreased markedly after enforcement of readily implementable administrative measures, ending the outbreak. However, tuberculin skin-test conversions among healthcare workers may not have been prevented by these measures. CDC guidelines for prevention of nosocomial transmission of TB should be implemented fully at all US hospitals.

Skin and mucous membrane contacts with blood during surgical procedures: risk and prevention.

OBJECTIVE: To study the epidemiology and preventability of blood contact with skin and mucous membranes during surgical procedures. DESIGN: Observers present at 1,382 surgical procedures recorded information about the procedure, the personnel present, and the contacts that occurred. SETTING: Four US teaching hospitals during 1990. PARTICIPANTS: Operating room personnel in five surgical specialties. MAIN OUTCOME MEASURES: Numbers and circumstances of contact between the patient's blood (or other infective fluids) and surgical personnel's mucous membranes (mucous membrane contacts) or skin (skin contacts, excluding percutaneous injuries). RESULTS: A total of 1,069 skin (including 620 hand, 258 body, and 172 face) and 32 mucous membrane (all affecting eyes) contacts were observed. Surgeons sustained most contacts (19% had > or = 1 skin contact and 0.5% had > or = 1 mucous membrane-eye contact). Hand contacts were 72% lower among surgeons who double gloved, and face contacts were prevented reliably by face shields. Mucous membrane-eye contacts were significantly less frequent in surgeons wearing eyeglasses and were absent in surgeons wearing goggles or face shields. Among surgeons, risk factors for skin contact depended on the area of contact: hand contacts were associated most closely with procedure duration (adjusted odds ratio [OR], 9.4; > or = 4 versus < 1 hour); body contacts (arms, legs, and torso) with estimated blood losses (adjusted OR, 8.4; > or = 1,000 versus < 100 mL); and face contacts, with orthopedic service (adjusted OR, 7.5 compared with general surgery). CONCLUSION: Skin and mucous membrane contacts are preventable by appropriate barrier precautions, yet occur commonly during surgery. Surgeons who perform procedures similar to those included in this study should strongly consider double gloving, changing gloves routinely during surgery, or both.

Use and efficacy of tuberculosis infection control practices at hospitals with previous outbreaks of multidrug-resistant tuberculosis.

OBJECTIVE: To evaluate the implementation and efficacy of selected Centers for Disease Control and Prevention guidelines for preventing spread of Mycobacterium tuberculosis. DESIGN: Analysis of prospective observational data. SETTING: Two medical centers where outbreaks of multidrug-resistant tuberculosis (TB) had occurred. PARTICIPANTS: All hospital inpatients who had active TB or who were placed in TB isolation and healthcare workers who were assigned to selected wards on which TB patients were treated. METHODS: During 1995 to 1997, study personnel prospectively recorded information on patients who had TB or were in TB isolation, performed observations of TB isolation rooms, and recorded tuberculin skin-test results of healthcare workers. Genetic typing of M tuberculosis isolates was performed by restriction fragment-length polymorphism analysis. RESULTS: We found that only 8.6% of patients placed in TB isolation proved to have TB; yet, 19% of patients with pulmonary TB were not isolated on the first day of hospital admission. Specimens were ordered for acid-fast bacillus smear and results received promptly, and most TB isolation rooms were under negative pressure. Among persons entering TB isolation rooms, 44.2% to 97.1% used an appropriate (particulate, high-efficiency particulate air or N95) respirator, depending on the hospital and year; others entering the rooms used a surgical mask or nothing. We did not find evidence of transmission of TB among healthcare workers (based on tuberculin skin-test results) or patients (based on epidemiological investigation and genetic typing). CONCLUSIONS: We found problems in implementation of some TB infection control measures, but no evidence of healthcare-associated transmission, possibly in part because of limitations in the number of patients and workers studied. Similar evaluations should be performed at hospitals treating TB patients to find inadequacies and guide improvements in infection control.

The prevalence of colonization with vancomycin-resistant Enterococcus at a Veterans' Affairs institution.

OBJECTIVE: To study vancomycin-resistant Enterococcus (VRE) prevalence, risk factors, and clustering among hospital inpatients. DESIGN: Rectal-swab prevalence culture survey conducted from February 5 to March 22, 1996. SETTING: The Veterans' Affairs Medical Center, Atlanta, Georgia. PATIENTS: Hospital (medical and surgical) inpatients. RESULTS: The overall VRE prevalence was 29% (42/147 patients). The VRE prevalence was 52% (38/73 patients) among patients who had received at least one of six specific antimicrobials during the preceding 120 days, compared with only 5% (4/74) among those who had not received the antimicrobials (relative risk, 9.6; P<.001). The longer the period (up to 120 days) during which antimicrobial use was studied, the more closely VRE status was predicted. Among 67 hospital patients in 28 multibed rooms, clustering of VRE among current roommates was not found. CONCLUSIONS: At this hospital with relatively high VRE prevalence, VRE colonization was related to antibiotic use but not to roommate VRE status. In hospitals with a similar VRE epidemiology, obtaining cultures from roommates of VRE-positive patients may not be as efficient a strategy for identifying VRE-colonized patients as obtaining screening cultures from patients who have received antimicrobials.

Secular trends in bloodstream infection caused by antimicrobial-resistant bacteria in New Jersey hospitals, 1991 to 1995.

INTRODUCTION: Antimicrobial resistance among bacteria is an increasing public health problem. In 1991, New Jersey was the first state to establish statewide, hospital-based surveillance for antimicrobial-resistant bacteria. METHODS: Each month, all 96 nonfederal New Jersey hospital laboratories complete a form listing the species identity and drug susceptibility results for selected antimicrobial-resistant bacteria isolated from blood cultures from hospital inpatients. Penicillin-resistant Streptococcus pneumoniae and aminoglycoside-resistant gram-negative rods were studied from 1991 to 1995. Vancomycin-resistant enterococci and imipenem-resistant gram-negative rods were studied from 1992 through 1995. RESULTS: From 1992 to 1995, the vancomycin-resistant enterococci bloodstream infection prevalence rate increased from 11 to 29 per 100,000 hospital admissions (p < 0.001); the rate was higher at larger hospitals, urban and inner-city hospitals, and teaching hospitals. From 1991 to 1995, the penicillin-resistant S. pneumoniae bloodstream infection rate increased from 1.1 to 9.9 per 100,000 admissions (p < 0.001). In contrast, bloodstream infection rates did not change significantly for imipenem-resistant (12.5 during 1992 and 14.1 during 1995, p = 0.4) or aminoglycoside-resistant (8.0 during 1991 and 6.8 during 1995, p = 0.4) gram-negative rods. CONCLUSIONS: We found that vancomycin-resistant enterococci and penicillin-resistant S. pneumoniae, but neither of two groups of antimicrobial-resistant gram-negative rods, are increasing rapidly in prevalence in New Jersey. Continued monitoring and interventions to slow these increases are needed.

Infection control in hemodialysis units.

Infectious complications of hemodialysis include bacterial infections caused by contaminated water or equipment, other bacterial infections (including vascular access infections), and bloodborne viruses (primarily the hepatitis B and C viruses). Infections caused by contaminated water and equipment can be prevented by a well-designed water-treatment system, routine cleaning and disinfection of system components, and routine bacteriologic monitoring of dialysis water and dialysis fluid. Standard precautions with additional measures recommended specifically for dialysis centers will prevent transmission of bacteria and viruses from patient to patient. These precautions include routine use of gloves, handwashing, and cleaning and disinfection of the external surface of the dialysis machine and other environmental surfaces. In addition, preventing transmission of hepatitis B virus infection requires vaccination of susceptible patients and staff, avoiding dialyzer reuse, and use of a dedicated room, dialysis machine, and staff members when treating patients chronically infected with this virus.

Study to determine the ability of clinical laboratories to detect antimicrobial-resistant Enterococcus spp. in Buenos Aires, Argentina.

Few reports of vancomycin-resistant enterococci have appeared outside the USA. Therefore, we evaluated the ability of five laboratories in Buenos Aires, Argentina, to perform susceptibility testing using the disk diffusion method. Laboratories had difficulty identifying the low- and intermediate-level vancomycin-resistant phenotypes. This suggests that the disk diffusion method used by laboratories abroad may fail to detect some vancomycin-resistant enterococci.

Use of the hepatitis-B vaccine and infection with hepatitis B and C among orthopaedic surgeons. The American Academy of Orthopaedic Surgeons Serosurvey Study Committee.

We used a questionnaire, with a guarantee of anonymity to the respondents, and conducted serological testing of 3411 attendees at the 1991 Annual Meeting of The American Academy of Orthopaedic Surgeons to evaluate the prevalences of infection with the hepatitis-B and C viruses and the use of the hepatitis-B vaccine among orthopaedic surgeons. There was evidence of infection with hepatitis B in 410 (13 per cent) of 3239 participants who had reported having no non-occupational risk factors; 2103 (65 per cent) reported that they had been immunized with the hepatitis-B vaccine. Of 3262 participants who reported having no non-occupational risk factors and who were evaluated for infection with hepatitis C, twenty-seven (less than 1 per cent) tested positive for the antibody to the hepatitis-C virus. The prevalence of previous infection with hepatitis B increased with increasing age; four (3 per cent) of 136 surgeons who were twenty to twenty-nine years old had evidence of infection, whereas ninety-six (27 per cent) of 360 surgeons who were sixty years old or more had evidence of infection. The prevalence of infection with hepatitis C also increased with increasing age; none of 135 surgeons who were twenty to twenty-nine years old had evidence of infection, and five (1 per cent) of 360 surgeons who were sixty years old or more had evidence of the virus. The prevalence of vaccination decreased steadily with age: 123 (90 per cent) of 136 surgeons who were twenty to twenty-nine years old reported that they had received the hepatitis-B vaccine, whereas 127 (35 per cent) of 360 surgeons who were sixty years old or more reported that they had received the vaccine. The prevalence of infection with hepatitis B or hepatitis C was not associated with the measured indices of exposure to the blood of patients (the number of cutaneous or mucosal contacts with blood that had occurred within the previous month or the number of percutaneous injuries that had occurred within the previous month or year, as recalled by the participants). In conclusion, the prevalence of immunization with the hepatitis-B vaccine was high among the orthopaedic surgeons studied. Although the prevalence of infection with the hepatitis-C virus was several times greater in the current investigation than has been reported in studies of blood donors in the United States, infection with this virus was not associated with the indices of occupational exposure to blood measured in this study.

National surveillance of dialysis associated diseases in the United States--1994.

Dialysis centers in the United States were surveyed in 1994 regarding a number of hemodialysis associated diseases and practices. A total of 2,449 centers, representing 206,884 patients and 50,314 staff members, responded. In 1994, 99% of centers used bicarbonate dialysate as the primary method of dialysis, 45% used high flux dialysis, and 75% reused dialyzers. Hepatitis B vaccine had been administered to 31% of patients and to 80% of staff members. Acute infection with hepatitis B virus occurred in 0.1% of patients and was more likely to be reported by centers with lower proportions of patients vaccinated against hepatitis B virus and those not using a separate room and dialysis machine to treat hepatitis B surface antigen positive patients. The prevalence of antibody to hepatitis C virus was 10.5% among patients and 1.9% among staff members and varied according to geographic region. Pyrogenic reactions in the absence of septicemia were reported by 22% of centers and were most highly associated with dialyzer reuse. Human immunodeficiency virus infection was reported to be present in 1.5% of patients; 37% of centers provided hemodialysis to one or more patients infected with human immunodeficiency virus.

National surveillance of dialysis associated diseases in the United States, 1995.

Chronic hemodialysis centers in the United States were surveyed in 1995 regarding a number of hemodialysis associated diseases and practices. A total of 2,647 centers, representing 224,954 patients and 54,194 staff members, responded. Seventy-seven percent of centers reported that they reused disposable dialyzers. At the end of 1995, 65% of patients were treated with an arteriovenous graft, 22% an arteriovenous fistula, and 13% a temporary or permanent central catheter. By the end of 1995, at least three doses of hepatitis B vaccine had been administered to 35% of patients and to 82% of staff members. Acute infection with the hepatitis B virus (HBV) occurred in 0.06% of patients, and was more likely to be reported by centers with lower proportions of patients vaccinated against HBV. The prevalence of antibody to hepatitis C virus (HCV) was 10.4% among patients and 2.0% among staff. At least one patient with vancomycin resistant enterococci (VRE) was reported by 11.5% of centers, more commonly by hospital (vs freestanding centers not located in hospitals) and government centers, and centers located in certain geographic areas. Vancomycin was received by 7.2% of patients in December 1995. The percentage of centers reporting patients with other pathogens was 7.9% for active tuberculosis, 39% for human immunodeficiency virus (HIV), and 40% for methicillin resistant Staphylococcus aureus (MRSA).

National surveillance of hemodialysis associated diseases in the United States, 1990.

To determine trends in several hemodialysis associated diseases and practices, the Centers for Disease Control (CDC), in collaboration with the Health Care Financing Administration (HCFA), performed a mail survey of chronic hemodialysis centers in the United States in 1990. Of 1,995 centers surveyed, 1,882 (94%) representing 140,608 patients and 36,907 staff members responded. As in recent years, the 1990 survey found that certain hemodialysis practices are increasing in frequency, including treatment of water with reverse osmosis and deionizer units; use of bicarbonate dialysate and high-flux dialysis; and reuse of disposable dialyzers (in 1990, 70% of centers reused dialyzers). Hepatitis B surface antigen (HBsAg) was present at low frequency in patients (incidence, 0.2%; prevalence, 1.2%) and staff (incidence, 0.04%; prevalence, 0.3%). Antibody to hepatitis B surface antigen was present in 20% of patients and 58% of staff, and was significantly related to levels of hepatitis B vaccine coverage. Pyrogenic reactions in the absence of septicemia were reported by 20% of centers and were associated with use of high-flux dialyzer membranes and reuse of dialyzers (particularly in centers where the maximum number of reuses was 40 or more). Septicemia among hemodialysis patients was reported by 49% of centers. Twenty-six percent of centers reported providing hemodialysis for patients infected with human immunodeficiency virus (HIV), and 1.1% of dialyzed patients had known HIV infection.