Navigation Links
Improved molecular tools streamline influenza testing and management
Date:4/17/2013

Philadelphia, PA, April 17, 2013 Over 40,000 people die each year in the United States from influenza-related diseases. In patients whose immune systems are compromised, antiviral therapy may be life-saving, but it needs to be initiated quickly. It is therefore crucial to diagnose and type the influenza rapidly. Scientists in the Netherlands have designed and evaluated a set of molecular assays that they say are a sensitive and good alternative for conventional diagnostic methods and can produce results in one day without the need for additional equipment. The results are published in The Journal of Molecular Diagnostics.

Currently the main circulating influenza viruses that cause disease in humans are the influenza A H3N2 and H1N1 subtypes together with influenza B virus. Re-emergence of a variant of the H1N1 influenza virus, which circulated in the population between 1977 and 2009, can also not be ruled out. Strategies to combat influenza virus-induced disease rely on vaccination as a preventive measure. In cases where vaccine efficacy is low, antiviral drugs may be used as prophylaxis.

Traditionally the adamantane and neuraminidase inhibitor class of drugs are available for both treatment and prophylaxis. However some subtypes are resistant to these. Most of the recently circulating influenza viruses are resistant to the adamantanes. In addition, the pre-pandemic H1N1 viruses, which emerged at the end of 2007, are naturally resistant to the neuraminidase inhibitor oseltamivir (Tamiflu). Sensitive and reproducible molecular assays are therefore essential for diagnosing influenza virus subtypes.

The investigators report on the design, validation, and evaluation of a set of real-time polymerase chain reaction (RT-PCR) assays for quantification and subtyping of human influenza A and B viruses from patient respiratory material, as well as four assays for detecting drug resistant mutations. For the evaluation of these assays, 245 respiratory specimens from 87 patients living in Asia, Europe, and the United States who were enrolled in a prospective study of influenza illness, including assessment of neuraminidase resistance, were analyzed. In addition 96 pre-pandemic influenza A/H1N1 viruses from the epidemic of 2007-2008 were analyzed by the H275Y assay to check the robustness of the assay.

The influenza quantification assay was used to check for virus positivity and to obtain virus particle counts for all analyzed samples. Influenza A viruses were then subtyped and tested for presence of oseltamivir resistance mutations using the resistance RT-PCR assays. In total, 129 respiratory specimens tested positive for influenza A and 60 for influenza B virus. One sample tested positive for both virus types.

"RT-PCR based assays have become the standard in most diagnostic laboratories worldwide in recent years," comments lead investigator Martin Schutten, PhD, Head of the Clinical Virology Unit at the Erasmus University, Rotterdam, the Netherlands. "The assays described here cover all currently circulating human influenza viruses and can detect major resistance mutations to oseltamivir. By introducing external quantification and internal standards, longitudinal assay performance can be monitored carefully and a virus particle count can be assigned to an analyzed sample.

"This algorithm can generate useful data to assist in the management of individual influenza virus infected patients and to evaluate clinical trials. Information regarding influenza virus (sub) type, viral load and antiviral susceptibility can be obtained within one working day. Alongside previously described assays that detect antiviral resistance associated mutations in 2009 pandemic H1N1 virus, these assays are a powerful tool for the clinical management of influenza virus infected patients," he concludes.

Although infection from H7N9, the new potential pandemic Influenza strain, or H5N1, a continuing pandemic threat since 1997, can be identified by exclusion (positive in the Influenza matrix RT-PCR but negative in RT-PCR typing), development of rapid typing RT-PCR for these potential pandemic viruses may be useful in complementing the existing set.


'/>"/>

Contact: David Sampson
jmdmedia@elsevier.com
215-239-3171
Elsevier Health Sciences
Source:Eurekalert

Related medicine news :

1. Mom Central Bloggers to Get a Sneak Peak at the New and Improved Adult Essentials Multi Vitamin Gummies
2. New Article Describing Improved Flu Response After Probiotic Use Published by eProbitoics
3. hCGTreatments / Diet Doc hCG Diets & Weight Loss Plans Announces hCG Diet Plans Aimed at Providing Patients Improved Sleep
4. Madison Chiropractors Move to New Location to Better Serve Their Patients with Improved Environment Focused on Holistic Healing
5. hCGTreatments / Diet Doc hCG Diets and Weight Loss Plans Announces The Newly Improved Prescription hCG Diet Plans Designed To Promote Fast Weight Loss Without Exercise
6. Improved detection of frontotemporal degeneration may aid clinical trial efforts
7. Study finds sexual health services for rural Latino men could be improved
8. Study shows need for improved empathic communication between hospice teams and caregivers
9. Grane Home Health Care and Grane Hospice Connects to Improved Care with CellTrak
10. InVite® Health Introduces New and Improved Antioxidant Product – Cocoa Tx™
11. BUSM authors propose potential epigenetic mechanisms for improved cancer therapy
Post Your Comments:
*Name:
*Comment:
*Email:
(Date:1/15/2017)... CA (PRWEB) , ... January 15, 2017 , ... ... their choice of best physicians in eight Bay Area counties for 2017. Almost ... the healthcare research company managing the award process. Results were announced the magazine’s ...
(Date:1/14/2017)... ... 2017 , ... Healthy living brand Moody Zook recently came ... With more and more people opting to go organic in their lifestyle, the ... to specific needs. , Moody Zook focused particularly on their newly launched activated ...
(Date:1/13/2017)... California (PRWEB) , ... January 13, 2017 , ... ... carbohydrates that raise blood sugar levels. Counting carbohydrates is as easy as checking ... the only nutrient that affects blood sugar levels. Despite being sugar-free, proteins can ...
(Date:1/13/2017)... ... January 13, 2017 , ... ... taken on the challenge of providing additional organic alternatives for customers who have ... of the brand’s new line of all-natural activated charcoal products, Moody Zook Chief ...
(Date:1/13/2017)... PA (PRWEB) , ... January 13, 2017 , ... "We ... and attractive to wear," said one of two inventors from Virginia Beach, Va. , ... to normally mundane braces. , The accessories allow braces to be customized to ...
Breaking Medicine News(10 mins):
(Date:1/12/2017)... -- BioPharmX Corporation (NYSE MKT: BPMX), a specialty pharmaceutical company developing ... this week,s Orlando Dermatology Aesthetic & Clinical (ODAC) Conference, which ... inflammation. The data will be shared in a ... at ODAC, which is being held Jan. 13-16 in ... ...
(Date:1/12/2017)...   TyrNovo , s NT219 drug candidate ... cancer drug resistance and would be ... NT219 is a novel proprietary ... ( IRS1/2 and STAT3) highly involved in ... .   NT219 has demonstrated ...
(Date:1/12/2017)... -- "Global Lung Cancer Vaccine Market & Pipeline ... trends in the global lung cancer vaccine market. ... available in the market. This report analyzes the ... in clinical pipeline and gives comprehensive clinical insight ... the lung cancer vaccines. Currently there are 9 ...
Breaking Medicine Technology: