Richard E. Hoffman

An outbreak of salmonellosis among children attending a reptile exhibit at a zoo

OBJECTIVE In January 1996, an outbreak of diarrhea caused by Salmonella Enteritidis occurred in children attending a Komodo dragon exhibit at a metropolitan zoo. We sought to determine the extent of the outbreak and mode of transmission. STUDY DESIGN A case-control study was conducted. Controls were randomly selected from zoo membership lists and matched to patients by age group and date of exhibit visit. RESULTS Of 65 patients identified, 39 had confirmed and 26 had suspected cases. The median age was 7 years (range, 3 months to 48 years); 55% were enrolled in the case-control study. No patients and two (4%) controls reported touching a dragon; however, 83% of patients but only 52% of controls touched the wooden barrier that surrounded the dragon pen (odds ratio = 4.0, 95% CI 1.2 to 13.9). Washing hands at the zoo after visiting the dragons was highly protective (OR = 0.14, 95% CI 0.03 to 0.7). Cultures from the patients, one dragon, and the exhibit barriers yielded Salmonella Enteritidis, phage type 8. On the basis of an attack rate of 4.3% among exhibit attendees under 13 years old on whom data were collected, we estimate that 315 additional cases of salmonellosis occurred among visitors in this age group. CONCLUSION This large outbreak demonstrates the importance of environmental contamination in the transmission of Salmonella from reptiles, and the protective value of hand washing. Recommendations regarding reptile exhibits and reptilian pets should emphasize this indirect route.

SERRATIA LIQUEFACIENS BLOODSTREAM INFECTIONS FROM CONTAMINATION OF EPOETIN ALFA AT A HEMODIALYSIS CENTER

BACKGROUND In a one month period, 10 Serratia liquefaciens bloodstream infections and 6 pyrogenic reactions occurred in outpatients at a hemodialysis center. METHODS We performed a cohort study of all hemodialysis sessions on days that staff members reported S. liquefaciens bloodstream infections or pyrogenic reactions. We reviewed procedures and cultured samples of water, medications, soaps, and hand lotions and swabs from the hands of personnel. RESULTS We analyzed 208 sessions involving 48 patients. In 12 sessions, patients had S. liquefaciens bloodstream infections, and in 8, patients had pyrogenic reactions without bloodstream infection. Sessions with infections or reactions were associated with higher median doses of epoetin alfa than the 188 other sessions (6500 vs. 4000 U, P=0.03) and were more common during afternoon or evening shifts than morning shifts (P=0.03). Sessions with infections or reactions were associated with doses of epoetin alfa of more than 4000 U (multivariate odds ratio, 4.0; 95 percent confidence interval, 1.3 to 12.3). A review of procedures revealed that preservative-free, single-use vials of epoetin alfa were punctured multiple times, and residual epoetin alfa from multiple vials was pooled and administered to patients. S. liquefaciens was isolated from pooled epoetin alfa, empty vials of epoetin alfa that had been pooled, antibacterial soap, and hand lotion. All the isolates were identical by pulsed-field gel electrophoresis. After the practice of pooling epoetin alfa was discontinued and the contaminated soap and lotion were replaced, no further S. liquefaciens bloodstream infections or pyrogenic reactions occurred at this hemodialysis facility. CONCLUSIONS Puncturing single-use vials multiple times and pooling preservative-free epoetin alfa caused this outbreak of bloodstream infections in a hemodialysis unit. To prevent similar outbreaks, medical personnel should follow the manufacturers guidelines for the use of preservative-free medications.

Adolescent suicide and household access to firearms in Colorado: results of a case-control study

PURPOSE To determine whether, compared with age- and sex-matched controls who did not commit suicide, adolescents who committed suicide by firearms were more likely to have had household access to firearms (after adjusting for significant risk factors for adolescent suicide). METHODS A case-control study design was used; case subjects were Colorado adolescents who committed suicide between 1991 and 1993; controls were sex- and age-matched adolescents who were randomly selected from the same school the subjects had attended. Interviews were conducted with the parent or guardian of cases and controls. RESULTS Of the 36 case subjects in this study, 67% committed suicide using a gun obtained from their home. Adolescent suicide victims who committed suicide by firearms were significantly more likely to have a firearm in their home (72%) than age- and sex-matched community controls (50%), after adjusting for significant risk factors. Conduct disorder and previous mental health treatment were also found to be independent risk factors for adolescent firearm suicide. CONCLUSIONS Two types of public health interventions to prevent adolescent firearm suicides are likely to be successful: (a) limiting household access to firearms, and (b) identifying adolescents at high risk of firearm suicide.

Risk Factors for Asthma Among Cosmetology Professionals in Colorado

Problem: After receiving several reports of occupational asthma among cosmetology professionals, we studied the prevalence, work-attributable risk, and tasks associated with asthma in this industry. Methods: We selected a stratified random sample of cosmeticians, manicurists, barbers, and cosmetologists holding licenses in Colorado for a mail survey instrument. Results: The prevalence of physician-diagnosed asthma among the 1883 respondents (68% response rate) was 9.3%; of these, 67 (38%) developed asthma after entering the cosmetology profession. Multivariate analyses showed that hairstyling, application of artificial nails, and shaving and honing were significantly associated with asthma arising in the course of employment (P < 0.005) with relative risks of 2.6–2.9. Conclusions: The increased risk of asthma with onset during employment among cosmetologists is probably attributable to their exposure to sensitizers and irritants in tasks demonstrated to be associated with asthma.

Pyrogenic reactions in patients undergoing cardiac catheterization associated with contaminated glass medicine cups.

Pyrogenic reactions are potentially life-threatening complications caused by bacterial endotoxin. After two cardiac catheterization patients developed rigors the same day, the procedures were halted and a case control study was conducted. To identify case patients (persons with rigors < or = 3 hr after catheterization during September 25-November 9, 1995), we reviewed medical records of all cardiac catheterization patients who had a blood culture or received intravenous meperidine. Twelve case patients and 40 randomly selected control patients were identified. No specific catheter was associated with case patients, but exposure to intracoronary-nitroglycerin (NTG) was (odds ratio = 12.0; 95% confidence interval 2.2, 75.6). NTG or indocyanine green dye was poured into glass medicine cups previously washed in an enzyme cleaner and then sterilized. The cleaner, used for an entire day, had elevated levels of gram-negative bacteria (> 10(4) colony forming units/mL) and endotoxin (434 endotoxin units [EU]/mL]); the reprocessed cups had no live bacteria but had elevated endotoxin levels (median 2,250 EU). Exposure to contaminated glass medicine cups probably resulted in pyrogenic reactions and contributed to death in two critically ill patients.

Public Health Response to 2 Clinical Cases of Blastomycosis in Colorado Residents

We summarize the public health response after the identification of 2 cases of pneumonia caused by Blastomyces dermatitidis infection in Colorado residents. The response to these cases emphasizes the need for physicians to add fungal infection to the list of differential diagnoses for patients who have refractory pneumonia, even those who live in areas of nonendemicity.

Firearm-Related Injury Surveillance in Colorado

CONTEXT The Colorado Department of Public Health and Environment uses existing data sources to identify and assess firearm-related deaths and injuries statewide. OBJECTIVE Implementation and evaluation of a surveillance system for fatal and hospitalized nonfatal firearm-related injuries. DESIGN Electronic death certificate and hospital discharge data are used to identify firearm-related deaths and injuries. Cases are confirmed and supplemental information is obtained from the Colorado Uniform Crime Report/Supplemental Homicide Report, police investigations, medical records, and newspaper accounts. Electronic data sets are created containing the information manually abstracted from these sources. SETTING Statewide. PARTICIPANTS Vital records, Colorado Hospital Association, medical records, Colorado Division of Criminal Justice, police departments. MAIN OUTCOME MEASURES Surveillance system simplicity, flexibility, sensitivity, and predictive value positive. RESULTS System-identified cases were compared with deaths and injuries identified from external sources such as hospital trauma registries, emergency department logs, and paramedic trip reports. The surveillance system is flexible, acceptable to reporting agencies, and sensitive, detecting 69% to 77% of firearm-related hospitalizations identified from external sources. The systems predictive value positive is high, with 89% of the potential cases confirmed as actual cases. Although simple in design, the surveillance system requires significant staff time to abstract information and because existing data sources are used, timeliness of the data is often delayed. Additionally, minor injuries (those requiring less than 24 hours or no hospitalization) are not detected. CONCLUSIONS Despite these limitations, the surveillance system is a valuable resources for information about firearm-related deaths and injuries, and represents an important first step in reducing the number and severity of firearm-related injuries in Colorado.