Jon Rosenberg

Factors Associated With Death or Hospitalization Due to Pandemic 2009 Influenza A(H1N1) Infection in California

CONTEXT Pandemic influenza A(H1N1) emerged rapidly in California in April 2009. Preliminary comparisons with seasonal influenza suggest that pandemic 2009 influenza A(H1N1) disproportionately affects younger ages and causes generally mild disease. OBJECTIVE To describe the clinical and epidemiologic features of pandemic 2009 influenza A(H1N1) cases that led to hospitalization or death. DESIGN, SETTING, AND PARTICIPANTS Statewide enhanced public health surveillance of California residents who were hospitalized or died with laboratory evidence of pandemic 2009 influenza A(H1N1) infection reported to the California Department of Public Health between April 23 and August 11, 2009. MAIN OUTCOME MEASURE Characteristics of hospitalized and fatal cases. RESULTS During the study period there were 1088 cases of hospitalization or death due to pandemic 2009 influenza A(H1N1) infection reported in California. The median age was 27 years (range, <1-92 years) and 68% (741/1088) had risk factors for seasonal influenza complications. Sixty-six percent (547/833) of those with chest radiographs performed had infiltrates and 31% (340/1088) required intensive care. Rapid antigen tests were falsely negative in 34% (208/618) of cases evaluated. Secondary bacterial infection was identified in 4% (46/1088). Twenty-one percent (183/884) received no antiviral treatment. Overall fatality was 11% (118/1088) and was highest (18%-20%) in persons aged 50 years or older. The most common causes of death were viral pneumonia and acute respiratory distress syndrome. CONCLUSIONS In the first 16 weeks of the current pandemic, the median age of hospitalized infected cases was younger than is common with seasonal influenza. Infants had the highest hospitalization rates and persons aged 50 years or older had the highest mortality rates once hospitalized. Most cases had established risk factors for complications of seasonal influenza.

Postoperative Serratia marcescens Wound Infections Traced to an Out-of-Hospital Source

From 25 August to 28 September 1994, 7 cardiovascular surgery (CVS) patients at a California hospital acquired postoperative Serratia marcescens infections, and 1 died. To identify the outbreak source, a cohort study was done of all 55 adults who underwent CVS at the hospital during the outbreak. Specimens from the hospital environment and from hands of selected staff were cultured. S. marcescens isolates were compared using restriction-endonuclease analysis and pulsed-field gel electrophoresis. Several risk factors for S. marcescens infection were identified, but hospital and hand cultures were negative. In October, a patient exposed to scrub nurse A (who wore artificial fingernails) and to another nurse-but not to other identified risk factors-became infected with the outbreak strain. Subsequent cultures from nurse As home identified the strain in a jar of exfoliant cream. Removal of the cream ended the outbreak. S. marcescens does not normally colonize human skin, but artificial nails may have facilitated transmission via nurse As hands.

Rhinovirus Outbreak in a Long Term Care Facility for Elderly Persons Associated with Unusually High Mortality

Abstract During a 6-week period in 2003, 56 residents and 26 staff developed respiratory illness in a long-term facility; 12 residents died. Seven of 13 respiratory specimens were culture-positive for rhinovirus; 6 of the isolates were serotype 82. In elderly populations, severe illness may be associated with organisms typically considered to be “benign,” such as rhinovirus.

Bloodstream infections in home infusion patients : The influence of race and needleless intravascular access devices

OBJECTIVES To determine the cause of increased central venous catheter-associated (CVC) bloodstream infection (BSI) rates in a cohort of pediatric hematology /oncology patients receiving home health care (HHC). METHODS A retrospective cohort study of hematology/oncology patients with CVCs receiving HHC from January 1992 through November 1994. RESULTS Of 182 patients with CVCs identified during the study period, 58 (32%) acquired 90 BSIs during 75,085 CVC days. BSI rates increased significantly from 1992 through 1994 (0.8 vs 1.0 vs 1.7 BSIs per 1000 CVC days; p < 0.005). Known risk factors, including catheter type, patient age less than 5 years, sex, or diagnosis, were not associated with increased BSI rates. After introduction of needleless devices for CVC access to the HHC regimen in May 1993, BSI rates increased 80% (from 0.81 to 1.46 BSIs/1000 CVC days, relative risk 1.8; p < 0.02). The only other significant risk factor was the race of the patient. White children had the lowest BSI rate before and after needleless-device introduction (0.4 vs 0.9 BSIs/1000 CVC days; p > 0.1), whereas black patients had the highest, unaffected by the introduction of these devices (2.5 BSIs/1000 CVC days). Both Hispanic (0.5 vs 1.6 BSIs/1000 CVC days) and Asian-American childrens (0.4 vs 1.5 BSIs/1000 CVC days) BSI rates increased threefold and fourfold after the introduction of needleless devices. CONCLUSIONS Our data suggest that pediatric hematology/oncology patients receiving HHC via needleless devices may have an increased risk of BSIs, and this risk may vary by race. We hypothesize that prevention of BSIs may require consideration of cultural, ethnic, and language differences when parents are trained to provide care for their children with CVCs in the home.

Genetic relatedness of hepatitis A virus isolates during a community‐wide outbreak

In 1993–94, a community‐wide outbreak of hepatitis A occurred in Stanislaus County, California. Stool specimens collected from a sample of 33 case patients were used to evaluate the duration of hepatitis A virus (HAV) excretion and the genetic relatedness of HAV isolates. Twenty‐four percent of the patients had a stool sample positive for HAV antigen by enzyme immunoassay, whereas 91% had at least one stool positive for HAV RNA by RT‐PCR amplification. Children were found to excrete low levels of HAV RNA for up to 10 weeks after the onset of symptoms. Analysis of the HAV VP1 amino terminus and VP1/P2A regions showed that a limited number of HAV isolates circulated during the epidemic and the majority of the cases were infected with the same strain. J. Med. Virol. 62:144–150, 2000.

A Summer Outbreak of Human Metapneumovirus Infection in a Long-Term-Care Facility

Human metapneumovirus (hMPV), a recently discovered paramyxovirus, is thought to be primarily a winter-spring pathogen affecting young children with a clinical presentation similar to that of respiratory syncytial virus. In June-July 2006, a respiratory outbreak in a long-term-care facility was reported to the local health department and investigated. Surveillance identified 26 residents and 13 staff with acute respiratory illness; 8 residents (31%) developed radiographically confirmed pneumonia, and 2 (5%) were hospitalized. Five of 14 respiratory specimens were positive by polymerase chain reaction assay for hMPV; sequencing identified genotype A. In institutionalized elderly persons, hMPV may be an important cause of respiratory outbreaks year-round.

Outbreak of Serratia marcescens Infections following Injection of Betamethasone Compounded at a Community Pharmacy

BACKGROUND In June 2001, following the report of 4 patients with Serratia marcescens meningitis who received epidural injections of betamethasone compounded at a community pharmacy, we initiated an outbreak investigation. METHODS All patients who received injections of betamethasone from the production lot common to the 4 patients were evaluated. A case patient was defined as a patient who received compounded betamethasone and had S. marcescens isolated from a sterile site or clinical and laboratory evidence of infection. We cultured all recovered betamethasone, environmental specimens from the pharmacy, and medications recovered from an ambulatory surgery center. The California Board of Pharmacy reviewed the procedures used to prepare the betamethasone. RESULTS We identified 11 patients with culture-confirmed S. marcescens (8 patients) or clinical infection (3 patients) following injection of compounded betamethasone from 25 May through 31 May 2001. Case patients had meningitis (5 patients, with 3 deaths), epidural abscesses (5 patients), or an infected hip (1 patient). S. marcescens was isolated from 35 (69%) of 51 betamethasone vials recovered, from pharmacy specimens of 1% carboxymethylcellulose stock solution, from pharmacy surfaces, and from multiple parenteral materials used at the ambulatory surgery center. Pulsed-field gel electrophoresis patterns of S. marcescens isolates of representative specimens from patients, the betamethasone, the pharmacy, and the ambulatory surgery center were identical. Deficient practices in compounding of betamethasone included inadequate autoclaving temperatures and failure to perform terminal sterilization. CONCLUSIONS This outbreak of serious S. marcescens infection followed improper compounding of betamethasone in a community pharmacy. Enforceable national standards for pharmaceutical compounding are needed to reduce the risk of such outbreaks.

Bloodstream infections in pediatric oncology outpatients: A new healthcare systems challenge

OBJECTIVE To investigate a perceived increase in central venous catheter (CVC)-associated bloodstream infections (BSIs) among pediatric hematology-oncology outpatients. DESIGN A case-control study. SETTING A pediatric hematology-oncology outpatient clinic at Fresno Childrens Hospital. PATIENTS Pediatric hematology-oncology clinic outpatients with CVCs at Fresno Childrens Hospital between November 1994 and October 1997. METHODS A case-patient was defined as any hematology-oncology outpatient with a CVC-associated BSI at Fresno Childrens Hospital from November 1996 to October 1997 (study period) without a localizable infection. To identify case-patients, we reviewed Fresno Childrens Hospital records for all hematology-oncology clinic patients, those with CVCs and those with CVCs and BSIs. Control-patients were randomly selected hematology-oncology outpatients with a CVC but no BSI during the study period. Case-patient and control-patient demographics, diagnoses, caretakers, catheter types, catheter care, and water exposure were compared. RESULTS Twenty-five case-patients had 42 CVC-associated BSIs during the study period. No significant increase in CVC-associated BSI rates occurred among pediatric hematology-oncology patients. However, there was a statistically significant increase in nonendogenous, gram-negative (eg, Pseudomonas species) BSIs during summer months (May-October) compared with the rest of the year. Case-patients and control-patients differed only in catheter type; case-patients were more likely than control-patients to have a transcutaneous CVC. Summertime recreational water exposures were similar and high in the two groups. CONCLUSIONS Hematology-oncology clinic patients with transcutaneous CVCs are at greater risk for CVC-associated BSI, particularly during the summer. Caretakers should be instructed on proper care of CVCs, particularly protection of CVCs during bathing and recreational summer water activities, to reduce the risk of nonendogenous, gram-negative BSIs.

Enhanced Control of an Outbreak of Mycoplasma pneumoniae Pneumonia with Azithromycin Prophylaxis

There are currently no recommended epidemic-control measures for Mycoplasma pneumoniae pneumonia outbreaks in closed communities. Previous studies have suggested the usefulness of chemoprophylaxis administered to close contacts of case-patients. To evaluate the effectiveness of various epidemic-control measures during an institutional outbreak, an observational study was undertaken during a very large outbreak of M. pneumoniae pneumonia at a facility for developmentally disabled residents (n = 142 cases). Control measures evaluated included no control, standard epidemic-control measures, and targeted azithromycin prophylaxis (500 mg on day 1, 250 mg/day on days 2-5) plus standard epidemic-control measures. The combined use of azithromycin prophylaxis and standard epidemic-control measures was associated with a significant reduction in the secondary attack rate. This study suggests that the addition of antibiotic prophylaxis to standard epidemic-control measures can be useful during institutional outbreaks of M. pneumoniae pneumonia.

Health Symptoms and Occupational Exposure to Flea Control Products among California Pet Handlers

A statewide telephone survey of health symptoms associated with occupational exposure to flea control products among California pet handlers was conducted in 1987 following several reports of ill workers. The 696 employees interviewed worked at veterinary clinics, pet stores, pet boarding kennels, pet grooming shops, and animal control facilities. Symptom incidence and frequency and flea control product use were reported for the 3 months prior to interview. Eye and skin symptoms and unusual tiredness were elevated among workers who applied flea control products to animals or facilities. After adjustment for potential confounders, these symptoms were elevated 64% to 258% among applicators as compared to nonapplicators who worked in the same facilities. Workers who used protective clothing and equipment and followed some protective work practices were not at increased symptom risk. Some specific flea control active ingredients and application procedures were associated with respiratory effects and with symptoms suggesting systemic pesticide poisoning.