Adamantane resistance in seasonal human influenza A viruses from Calgary, Alberta (January 2007 to August 2008).

The available antivirals for the treatment and prophylaxis of influenza A infections include the adamantanes (amantadine and rimantadine), which are matrix (M2) protein inhibitors, and the neuraminidase inhibitors (oseltamivir and zanamivir). Resistance to the adamantanes is conferred by mutations at amino acid positions 26, 27, 30, 31 or 34 within the M2 protein of influenza A viruses. A significant increase in adamantane resistance has been reported worldwide since 2003, reflected by a similar increase in Canada.

Detection of adenoviruses.

The human adenovirus (hAdV) group is represented by 52 serotypes that have been reported to cause a broad range of clinical manifestations including respiratory tract infections, acute conjunctivitis, cystitis, gastroenteritis, and systemic infections. Conventional methods for detection of hAdVs include electron microscopy, antigen detection, and virus isolation in cell culture. Implementation of real-time PCR assays has increased the sensitivity and speed of detection, and allowed for rapid quantification and serotyping.

Z-FA-FMK as a novel potent inhibitor of reovirus pathogenesis and oncolysis in vivo.

Background: Respiratory enteric orphan (reo)virus is a promising oncolytic viral candidate. Reoviral anticancer therapy is currently undergoing multiple clinical trials targeting various human cancers; however, there is no effective reoviral inhibitor that can be used to block unwanted reovirus replication during reoviral anticancer therapy.

Methods: Studies were conducted with transformed or normal cells in vitro and in vivo to characterize viral replication in the presence or absence of chemical inhibitors.

Enhanced viral etiological diagnosis of respiratory system infection outbreaks by use of a multitarget nucleic acid amplification assay.

A study was undertaken to assess the utility of the xTAG respiratory viral panel (RVP) for enhanced laboratory investigation of respiratory outbreaks. Specimens (n = 1,108) from 244 suspected respiratory virus outbreaks in 2006 and 2007 in Alberta, Canada, were included in the study. Testing by direct fluorescent antigen detection (DFA) and various in-house nucleic acid amplification tests (NATs) for common respiratory viruses provided an etiological diagnosis in 177 outbreaks (72.

Design and validation of real-time reverse transcription-PCR assays for detection of pandemic (H1N1) 2009 virus.

Tracking novel influenza viruses which have the potential to cause pandemics, such as the pandemic (H1N1) 2009 virus, is a public health priority. Pandemic (H1N1) 2009 virus was first identified in Mexico in April 2009 and spread worldwide over a short period of time. Well-validated diagnostic tools that are rapid, sensitive, and specific for the detection and tracking of this virus are needed.

Surveillance of mosquito-borne viruses in Alberta using reverse transcription polymerase chain reaction with generic primers.

Mosquitoes collected during 2003, 2004, and 2005 in Alberta, Canada, were screened for the presence of a wide range of arboviruses by reverse transcription-polymerase chain reaction (RT-PCR). Nucleic acid extracts from mosquito slurries were amplified using universal primers designed to detect viruses belonging to the Flavivirus genus of the Flaviviridae family and California and Bunyamwera serogroups of the Bunyavirus genus within the Bunyaviridae family. Species-specific detection of Western equine encephalitis virus and Eastern equine encephalitis virus was also performed.

Microfluidic device for dielectrophoresis manipulation and electrodisruption of respiratory pathogen Bordetella pertussis.

A miniaturized microfluidic device was developed to facilitate electromanipulation of bacterial respiratory pathogens. The device comprises a microchip with circular aluminum electrodes patterned on glass, which is housed in a microfluidic system fabricated utilizing polydimethylsiloxane. The device provides sample preparation capability by exploiting positive dielectrophoresis (DEP) in conjunction with pulsed voltage for manipulation and disruption of Bordetella pertussis bacterial cells.

Viral infection in adults hospitalized with community-acquired pneumonia: prevalence, pathogens, and presentation.

Background: The potential role of respiratory viruses in the natural history of community-acquired pneumonia (CAP) in adults has not been well described since the advent of nucleic amplification tests (NATs).

Methods: From 2004 to 2006, adults with CAP who were admitted to five hospitals were prospectively enrolled in the study, and clinical data, cultures, serology, and nasopharyngeal swabs were obtained. NATs from swabs were tested for influenza, human metapneumovirus (hMPV), respiratory syncytial virus (RSV), rhinovirus, parainfluenza virus 1-4, coronaviruses (OC43, 229E, and NL63), and adenovirus.

Comparison of the Luminex xTAG respiratory viral panel with in-house nucleic acid amplification tests for diagnosis of respiratory virus infections.

Detection of respiratory viruses using sensitive real-time nucleic acid amplification tests (NATs) is invaluable for patient and outbreak management. However, the wide range of potential respiratory virus pathogens makes testing using individual real-time NATs expensive and laborious. The objective of this study was to compare the detection of respiratory virus targets using the Luminex xTAG respiratory viral panel (RVP) assay with individual real-time NATs used at the Provincial Laboratory of Public Health, Calgary, Alberta, Canada.

Comparison between the clinical and laboratory features of enterovirus and West Nile virus infections.

The seasonality and clinical features of enterovirus (EV) infections overlap with those of West Nile virus (WNV). The purpose of this study was to determine the frequency of EV detection in patients being tested for WNV and to look for features that could be used to distinguish between infections with these two viruses. Nucleic acid amplification testing (NAT) for EV was performed on all plasma samples submitted for WNV testing in 2003 and 2004.

Use of throat swab or saliva specimens for detection of respiratory viruses in children.

Background: Nasopharyngeal (NP) specimens are commonly used for the detection of respiratory viruses, but throat and saliva specimens are easier to obtain. The objective of this study was to compare the viral yield of direct fluorescent antigen detection of NP specimens and nucleic acid amplification tests (NAT) of direct fluorescent antigen-negative NP specimens with the viral yield of NAT of throat swab and saliva specimens.

Methods: NP, throat swab, and saliva specimens were obtained from children and adolescents aged View Article and Find Full Text PDF

Detection of a broad range of human adenoviruses in respiratory tract samples using a sensitive multiplex real-time PCR assay.

Human adenoviruses (hAdVs) are associated with acute respiratory tract infections in pediatric populations and have been identified as a cause of outbreaks in institutional settings. Rapid diagnosis of hAdV infection is critical for appropriate and timely management. This study reports the design and validation of a sensitive and specific multiplex real-time PCR for the detection of a broad range of hAdV serotypes in respiratory samples.

Adamantane resistance in circulating human influenza A viruses from Alberta, Canada (1970-2007).

Mutation in one of five key amino acid residues (positions 26, 27, 30, 31 and 34) within the M2 protein of influenza A viruses, leads to resistance against the adamantane class of anti-influenza drugs. To investigate the emergence and prevalence of adamantane resistance in Alberta, Canada (between 1970 and 2007), 381 influenza A positive samples (original patient specimens) or isolates (virus cultured from patient specimens) were analyzed for changes in these critical amino acid residues. Our results show a significant increase in adamantane resistance in circulating H3N2 viruses in Alberta from 2005 and 2006 when compared with those from 2004 (p<0.

Respiratory virus surveillance and outbreak investigation.

Sensitive, rapid detection of respiratory viruses is needed for surveillance and for investigation of epidemiologically linked cases. The utility of rapid antigen-based methods for detection of common respiratory viruses and to confirm the cause of outbreaks is well established. However, nucleic acid amplification tests (NATs) offer some benefits above antigen or culture-based procedures, with the main advantages being sensitivity and range of pathogens detectable.

Nucleic acid amplification tests for detection of respiratory viruses.

Nucleic acid amplification tests (NATs) are increasingly being used for diagnosis of respiratory virus infections. The most familiar formats use DNA or RNA target amplification methods for enhanced sensitivity above culture and antigen-based procedures. Although gel and plate-hybridisation methods are still utilised for analysis of amplified products, detection using "real-time" methods which do not require handling of amplified products are favoured in many laboratories.

Human metapneumovirus pneumonia in adults: results of a prospective study.

We prospectively collected clinical, laboratory, and radiographic data regarding community-acquired human metapneumovirus (hMPV) infection in consecutive adults hospitalized with pneumonia. hMPV infection was diagnosed using highly accurate reverse-transcription-polymerase chain reaction analysis of nasopharyngeal samples. Eight (4%) of 193 patients had hMPV RNA present, all detected during influenza season.

Integrated microfluidic systems for sample preparation and detection of respiratory pathogen Bordetella pertussis.

An integrated microfluidic system for combined manipulation, pre-concentration, and lysis of samples containing Bordetella pertussis by dielectrophoresis and electroporation has been developed and implemented. The microfluidic device was able to pre-concentrate the amount of B. pertussis cells present in 200 microl of a B.

Diagnosis and epidemiological studies of human metapneumovirus using real-time PCR.

Background: Human metapneumovirus (hMPV) is prevalent in children, the elderly and immunocompromised individuals, but available epidemiological data is limited.

Objectives: (1) To develop and validate a real-time PCR method for hMPV diagnosis. (2) To determine the percentage of hMPV in respiratory specimens from the community and its association with outbreaks in our geographic area.

Nucleic acid amplification tests for the detection and analysis of respiratory viruses: the future for diagnostics?

Nucleic acid amplification tests have the potential to revolutionize our diagnosis of respiratory virus infections and enable us to identify and monitor the impact of newly identified viruses on public health. However, the wide range of potential pathogens that can cause similar respiratory symptoms and disease makes application of diagnostic assays based on detection of DNA and RNA both complex and expensive. There is a need to evaluate new technologies and automation beyond conventional or real-time amplification and detection methods to address broad-spectrum diagnosis and for pandemic preparedness.

Enhanced identification of viral and atypical bacterial pathogens in lower respiratory tract samples with nucleic acid amplification tests.

The advantages of nucleic acid amplification tests (NAT) over conventional methods for the detection of pathogens in lower respiratory tract samples have not been established. NAT for respiratory pathogens were performed on 439 endotracheal tube (ETT) and bronchoalveolar lavage (BAL) samples. A potential pathogen was detected in 87 samples.