ABSTRACT
BACKGROUND: Human enteroviruses (HEVs) are common pathogens which cause a broad spectrum of illnesses ranging from asymptomatic infection to acute myocarditis and aseptic meningitis. The neutralization assay for serotype determination is labor-intensive and time-consuming. There is a need for a methodology that is more rapid and widely accessible. OBJECTIVES: Our goals were to develop an algorithm to type enteroviruses which combines both serologic typing, based on indirect immunofluorescence assay (IFA) using type-specific monoclonal antibodies (mAbs) and genotyping, by DNA sequence analysis and to assess the correlation of both IFA and genotyping to traditional viral neutralization by type-specific antisera. STUDY DESIGN: Clinical specimens initially determined to be enterovirus positive by nucleic acid detection were grown in cell culture and typed using mAbs. Specimens that could not be typed by mAbs were subject to molecular analysis. Genotyping was performed by a combination of either a primary or semi-nested RT-PCR for a region within VP3/VP1 and followed by direct DNA sequencing of PCR products. Database homology comparisons and phylogenetic analysis were performed based on a defined region (303 nt) within the VP1 gene. RESULTS: We inoculated 134 enterovirus nucleic acid amplification-positive specimens into culture and 115 (86%) of these isolates were successfully typed by this algorithm. We have demonstrated a strong correlation between serotyping by viral neutralization to both IFA by type-specific mAbs and genotyping. CONCLUSIONS: Typing of human enteroviruses can be effectively performed using an integration of antibody-based and molecular methods.
Subject(s)
Antigens, Viral/analysis , Enterovirus/classification , RNA, Viral/genetics , Algorithms , Cluster Analysis , Enterovirus/genetics , Enterovirus/immunology , Fluorescent Antibody Technique, Direct/methods , Genotype , Humans , Molecular Sequence Data , Neutralization Tests , Phylogeny , Reverse Transcriptase Polymerase Chain Reaction/methods , Sequence Analysis, DNA , Sequence Homology , SerotypingABSTRACT
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.
Subject(s)
Alphainfluenzavirus/isolation & purification , Influenza, Human/epidemiology , Population Surveillance/methods , Seasons , California/epidemiology , Humans , Influenza, Human/mortality , Models, OrganizationalABSTRACT
Clinical similarities and shared seasonality suggested a relationship between adenovirus infection and Kawasaki disease. We performed adenovirus serology and quantitative polymerase chain reaction for both adenovirus and adeno-associated virus in patients with acute Kawasaki disease. No evidence was found to suggest a link between either virus and Kawasaki disease.
