To evaluate the efficacy of giving a third dose of recombinant hepatitis B vaccine to healthcare workers who already had received two doses of serum-derived vaccine, which is no longer available in the United States.

Volunteers who already had received two standard doses of serum-derived vaccine were given a third dose of either serum or recombinant vaccine in a double-blind fashion. Antibodies to hepatitis B surface antigen were measured at the time of the third immunization, three months later, and one year after the third immunization.

U.S. Army Medical Center, El Paso, Texas.

One hundred healthy healthcare workers.

Three months after receiving the third immunization, the serum vaccine group had significantly higher titers than the recombinant vaccine group (P= 0.018). One year after receiving the third immunization, those who received the combined regimen had a mean hepatitis B surface antibody titer less than half that of those who received three doses of serum-derived vaccine. However, both regimens resulted in titers that are considered to confer immunity.

A regimen that combines serum and recombinant hepatitis B vaccines may not produce as high an antibody level as three doses of the same vaccine. Those who began immunization with serum vaccine and concluded with recombinant vaccine should be monitored for an accelerated drop in serum antibodies.

To study risk factors for the highly variable local colonization rates with unrelated Enterobacter species strains previously found in 22 Swedish neonatal units (0% to 32.4% of the infants).

The fecal Enterobacter species carriage rates among 953 infants in the 22 special-care neonatal units were correlated with variables related to the ward (size, crowding, staffing, work load, antibiotic usage, level of care, hygienic precautions), and the hospital (temperature of water supplied, geographical location).

The average Enterobacter species carriage rate was highest at seven days of age (17% of the infants) and then declined to 3%. Only location of the hospital in an area with warmer climate according to horticultural zone showed an association with Enterobacter species carriage in multivariate analysis (P= 0.005).

Although Enterobacter species mainly cause nosocomially acquired infections, the occurrence of the organism in special-care neonatal units seemed to be determined more by extrahospital than by intrahospital factors.

To devise a system for surveying the frequency of nosocomial infections in a tertiary care hospital in a developing country.

Prospective selective surveillance by nurses of the charts of patients at high risk for nosocomial infections, as identified by a form completed by resident physicians. The sensitivity, specificity, and predictive value of this method of selective surveillance were compared with those for total prospective chart review by two infectious disease specialists.

A university hospital in northeastern Brazil.

All patients hospitalized for more than 72 hours with an identified risk factor for nosocomial infection.

The ratio of nosocomial infections to 100 discharges was 13.4 and the incidence density was 11.2/1,000 patient days. The surveillance method demonstrated a sensitivity of 74% and a specificity of 99.7%. Positive predictive value was 93%, negative predictive value was 99%, and overall accuracy was 98%.

This method of selective surveillance for nosocomial infections based on risk factors identified by physicians demonstrated excellent predictive value and overall accuracy and may be of use to other hospitals that lack a nursing care plan book such as the Kardex. The relative frequency of nosocomial infections significantly exceeded the rates reported from hospitals in developed countries.

To survey the attitudes of healthcare personnel regarding influenza immunization.

A questionnaire was given to all hospital employees.

A 650-bed community teaching hospital.

Employees were offered an in-service regarding influenza immunization in October 1991. Influenza immunization was given free of charge by Employee Health Services from October to December 1991. One thousand fifty-six employees (30.2%) received influenza vaccines. Survey forms were distributed with paychecks to all employees during the second half of January 1992. Completed survey forms were returned during the next 2 weeks.

One thousand two hundred three of the 3,501 (34.3%) questionnaires were returned. Some of the survey forms were not completely filled out. A total of 28.1% of male employees (202/717) and 35.4% of female employees (987/2783) (p<.01) responded. Mean years employed were 11.35 ± 7.57 for respondents and 9.30 ± 7.39 for all employees (p<.001). Four hundred sixty-one respondents (38.4%) received the influenza vaccine and 734 (6 1.4%) did not. Among the respondents, employees who were older or working full time were more likely to receive the vaccine. Proportionally, more respondents who received the vaccine attended the in-service, although only 8.7% of those immunized attributed their receiving influenza vaccine to the in-service. More physician respondents were vaccinated. Tbe respondents who received influenza vaccine were more likely to have received the vaccine during the past 2 years (p<.001). The major reasons given for not receiving the vaccine were “bad side effects” and “do not like shots.” The major side effect of influenza immunization was a “sore arm.” Multivariate analysis suggested that the in-service was not associated with obtaining the vaccine.

The in-service regarding influenza immunization seemed to have a negligible influence. Most employees who received the vaccine had previous influenza immunization. There were no major side effects of influenza immunization. “Bad side effects” and “do not like shots” were major reasons given for not receiving influenza vaccine.

To assess postoperative exposure to parenteral antibiotics and coded discharge diagnoses of infection as markers of nosocomial infection, postoperative morbidity, and potentially inappropriate antibiotic use after cesarean section.

Retrospective cohort study to compare automated markers with the criterion of record review.

Tertiary care hospital.

Women admitted to a large teaching hospital after April 15, 1987, and discharged before October 1, 1989, who underwent a nonrepeat, nonelective cesarean section and had received prophylaxis with a cephalosporin.

Antibiotic exposure and discharge diagnosis codes were obtained from a large electronic hospital data base. A sample of charts was reviewed to determine the presence of infection, other postoperative complications, and postoperative antibiotic exposure.

A total of 2,197 women who had undergone a nonrepeat nonelective cesarean section were included in the study cohort. These women were assigned to 6 subgroups based on postoperative antibiotic exposure status and discharge codes suggesting endometritis, other postoperative infection, or no infection. Review of 457 records indicated that the overall infection rate was 9%. Eight percent of all the patients had a coded diagnosis for infection, and 16% received some parenteral antibiotics after the first postoperative day. Exposure to at least 2 days of parenteral postoperative antibiotics was the best marker by which to discriminate between infected and uninfected patients, with a sensitivity of 81 %, a specificity of 95%, and a positive predictive value of 61% for detecting infection. The corresponding figures for coded diagnoses for infection had rates of 65%, 97%, and 74%, respectively. The combination of discharge codes and exposure to parenteral postoperative antibiotics resulted in a more accurate but less sensitive marker for nosocomial infections, with a positive predictive value of 94% and a sensitivity of 59%. The groups with discordant parenteral postoperative antibiotics exposure and discharge codes for infection were enriched for errors in coding, noninfectious morbidity, and unexplained antibiotic use. Less than 1% of the entire cohort had ≥ 2 days of parenteral postoperative antibiotics without any reason apparent in the medical record.

Parenteral postoperative antibiotic exposure determined from automated pharmacy records correlated with the results of the more labor-intensive manual review of medical records for the identification of nosocomial infection. In addition, information on antibiotic exposure combined with coded discharge diagnoses provided a rapid screen to identify subgroups of patients with higher rates of infectious and noninfectious morbidity, unexplained antibiotic use, and errors in discharge coding. Information derived from electronic data bases created for administrative purposes may be useful as a marker for infectious complications, inappropriate antibiotic prescribing, and other issues related to total quality hospital monitoring.

The investigation and control of an outbreak of nosocomial Pseudomonas cepacia respiratory tract colonization and infection.

Epidemiologic investigation based on infection control surveillance data, including definition and characterization of case patients, environmental cultures based on epidemiologic information, and institution of control measures based on study results.

A 1,171 -bed, university-affiliated tertiary care hospital.

Between January 1, 1988, and June 30, 1989, 127 patients were culture-positive for P cepacia, 117 (92%) of whom were culture-positive from sputum and were treated in the intensive care unit. Review of respiratory care procedures revealed that when mechanical ventilators were serviced between patients, the electronic temperature probes used with servo-controlled humidifiers were wiped with the same odor-counteractant cleaning solution used on ventilator cabinets, P cepacia was isolated from nine of 12 in-use temperature probe tips, three of which were from patients with negative sputum cultures for P cepacia, one of whom subsequently developed culture positivity for P cepacia.

P cepacia also was isolated from the diluted odor-counteractant solution. Following the institution of a disinfection procedure for temperature probe tips, the incidence of P cepacia sputum culture positivity in ICU patients fell significantly compared to the outbreak period (138 of 5,225 discharges versus 52 of 3,678 discharges, P<0.01).

This investigation identified contamination of reusable electronic temperature probes as a source of nosocomial respiratory infection due to P cepacia and emphasizes the need to carefully evaluate disinfection practices for reusable patient care equipment.