Role of real-time reverse transcription polymerase chain reaction for detection of respiratory viruses in critically ill children with respiratory disease: Is it time for a change in algorithm?

OBJECTIVES: To identify the respiratory viral pathogens associated with acute lower respiratory tract infection in critically ill pediatric patients by using real-time reverse transcription-polymerase chain reaction, and compare results with those of direct fluorescence antibody assay testing. DESIGN: Observational cohort study. SETTING: Pediatric intensive care unit at a tertiary care academic hospital. PATIENTS: Pediatric patients admitted to the pediatric intensive care unit with severe respiratory symptoms consistent with viral lower respiratory tract infection. INTERVENTIONS: None. MEASUREMENTS: Respiratory samples of pediatric patients admitted to the pediatric intensive care unit with severe respiratory symptoms between January 2008 and July 2009 were tested with direct fluorescence antibody assay and real-time reverse transcription-polymerase chain reaction. MAIN RESULTS: At least one viral agent was detected in 70.5% of specimens by real-time reverse transcription-polymerase chain reaction and in 16.5% by direct fluorescence antibody assay (p < .001). Real-time reverse transcription-polymerase chain reaction increased the total viral yield five-fold compared to direct fluorescence antibody assay. Rhinovirus was the most commonly identified virus (41.6%). For viruses included in the direct fluorescence antibody assay panel, direct fluorescence antibody assay had a sensitivity of 0.42 (95% confidence interval 0.25-0.61) and a specificity of 1 (95% confidence interval 0.86-1.00) compared with real-time reverse transcription-polymerase chain reaction. Coinfections were not uncommon, in particular with rhinovirus, and these patients tended to have higher mortality. CONCLUSIONS: Direct fluorescence antibody assay testing is a suboptimal method for the detection of respiratory viruses in critically ill children with lower respiratory tract infection. Given the importance of a prompt and accurate viral diagnosis for this group of patients, we suggest that real-time reverse transcription-polymerase chain reaction becomes part of the routine diagnostic algorithm in critically ill children when a viral etiology is suspected, even if conventional tests yield a negative result.

Rapid influenza antigen test for diagnosis of pandemic (H1N1) 2009.

We compared the QuickVue Influenza test with PCR for diagnosing pandemic (H1N1) 2009 in 404 persons with influenza-like illness. Overall sensitivity, specificity, and positive and negative predictive values were 66%, 84%, 84%, and 64%, respectively. Rapid test results should be interpreted cautiously when pandemic (H1N1) 2009 virus is suspected.

Rhinovirus associated with severe lower respiratory tract infections in children.

Rhinovirus is a respiratory virus most typically associated with the common cold and asthma exacerbations, and has not traditionally been considered to play a major role in severe lower respiratory tract infections (LRTIs). As part of a surveillance program for respiratory pathogens of public health importance, children consecutively admitted to intensive care for LRTI at a large tertiary children's hospital were tested with polymerase chain reaction for 11 respiratory viruses and Mycoplasma pneumoniae from February 21 to October 31, 2007; 43 cases were enrolled and rhinovirus was the most frequently detected pathogen, with 21 (49%) positive. Rhinovirus cases frequently were young (median age, 1.4 years [range, 44 days-15 years]), hospitalized for pneumonia (10; 48%), had chronic underlying illnesses (15; 71%), had abnormal chest radiographs (18; 86%), required mechanical ventilation (12; 57%), and had prolonged hospitalization (median length, 7 days [range, 1-29 days]). Coinfection with other viruses or bacteria was common (10; 47%). Rhinovirus may be associated with more severe LRTI in children than previously reported, particularly in the noninfluenza, nonrespiratory syncytial virus season.

Creating a model program for influenza surveillance in California: results from the 2005-2006 influenza season.

BACKGROUND: Influenza surveillance is valuable for monitoring trends in influenza-related morbidity and mortality. Using the 2005-2006 influenza season as an example, this paper describes a comprehensive influenza surveillance program used by the California Department of Public Health (CDPH). METHODS: Data collected from patients evaluated for acute respiratory illness in a given week were reported and summarized the following week, including (1) electronic hospital pneumonia and influenza admission and antiviral usage records from Kaiser Permanente, (2) sentinel provider influenza-like illness (ILI) reports, (3) severe pediatric influenza case reports (e.g., children either hospitalized in intensive care or expired), (4) school clinic ILI evaluations, and (5) positive influenza test results from a network of academic, hospital, commercial, and public health laboratories and the state CDPH Viral and Rickettsial Disease Laboratory. RESULTS: Influenza activity in California in the 2005-2006 season was moderate in severity; all clinical and laboratory markers rose and fell consistently. Extensive laboratory characterization identified the predominant circulating virus strain as A/California/7/2004(H3N2), which was a component of the 2005-2006 influenza vaccine; 96% of samples tested showed adamantane resistance. CONCLUSIONS: By using multiple, complementary surveillance methods coupled with a strong laboratory component, the CDPH has developed a simple, flexible, stable, and widely accepted influenza surveillance system that can monitor trends in statewide influenza activity, ascertain the correlation between circulating strains with vaccine strains, and assist with detection of new strain variants. The methods described can serve as a model for influenza surveillance in other states.

Influenza vaccination among health care personnel in California: 2010-2011 influenza season.

BACKGROUND: Influenza vaccination among health care personnel (HCP) is a key measure to prevent influenza infection and transmission in health care settings. This study described influenza vaccination coverage among employees in various health care settings in California and examined factors associated with HCP influenza vaccination. METHODS: This study analyzed data from 111 facilities recruited through statewide invitation. Data on facility characteristics, vaccination programs, and vaccination receipt within and outside facilities were collected using Web-based questionnaires. Employees were defined as all persons in the facility payroll system regardless of patient contact. Facility-level employee vaccination coverage was calculated for 91 facilities. RESULTS: The mean employee influenza vaccination coverage was 60.7% overall: 64.0% for acute care hospitals (n = 30), 54.7% for long-term care facilities (n = 22), 59.4% for ambulatory surgery centers (n = 8), 58.6% for dialysis centers (n = 25), and 77.2% for physician practices (n = 6). Vaccination promotion methods such as risk-benefit education, personal reminders, and vaccination data tracking and feedback were significantly associated with increased vaccination coverage. CONCLUSION: The study findings suggest some variations in HCP vaccination coverage by type of health care setting as well as substantial challenges in reaching the Healthy People 2020 goal of 90%. Health care facilities need to use comprehensive promotion methods to improve HCP influenza vaccinations.