Navigation Links
Study suggests some drug resistance to influenza B medications

Use of certain common antiviral drugs during a recent influenza B epidemic in Japan showed the development of viruses with partial resistance to the drugs, according to a study in the April 4 issue of JAMA.

Two antiviral drugs, zanamivir and oseltamivir, which are a type of drugs known as neuraminidase inhibitors, have been effective against influenza and are used extensively. There has been documented evidence of the emergence of oseltamivir-resistant type A viruses, but similar information on influenza B viruses has been limited. Influenza B viruses are associated with annual outbreaks of illness and increased death rates worldwide, according to background information in the article.

Shuji Hatakeyama, M.D., Ph.D., of the University of Tokyo, Japan, and colleagues examined the prevalence and transmissibility of influenza B viruses with reduced sensitivity to neuraminidase inhibitors in Japan, where zanamivir and oseltamivir are now used more extensively than anywhere else in the world. In the winter of 2004-2005, an influenza B virus caused a widespread epidemic in Japan, creating an opportunity to assess the effectiveness of neuraminidase inhibitors. The researchers collected influenza B isolates from 74 children before and after oseltamivir therapy and from 348 untreated patients with influenza (including 66 adults). Four hundred twenty-two viruses from untreated patients and 74 samples from patients after oseltamivir therapy were analyzed.

The researchers identified a variant with reduced drug sensitivity in one (1.4 percent) of the 74 children who had received oseltamivir, and seven (1.7 percent) of the 422 influenza B viruses isolated from untreated patients were found to have reduced sensitivity to zanamivir, oseltamivir, or both. Review of the clinical and viral genetic information available on these seven patients indicated that four were likely infected in a community setting, while the remaining three were probably infected thr ough contact with siblings shedding the mutant viruses.

“Continued surveillance for the emergence or spread of neuraminidase inhibitor–resistant influenza viruses is critically important,?the authors write. “Further evaluation of the biological properties of neuraminidase inhibitor–resistant influenza viruses is needed to fully assess their pathogenicity in humans.?

(JAMA. 2007;297:1435-1442. Available pre-embargo to the media at www.jamamedia.org)

Editor’s Note: Please see the article for additional information, including other authors, author contributions and affiliations, financial disclosures, funding and support, etc.


Editorial: News About Influenza B Drug Resistance That Cannot Be Ignored

In an accompanying editorial, Anne Moscona, M.D., of Weill Medical College of Cornell University, New York, and Jennifer McKimm-Breschkin, Ph.D., of Molecular and Health Technologies, Parkville, South Victoria, Australia, comment on the findings concerning possible drug resistance to influenza B medications.

“The report by Hatakeyama et al raises more questions than it answers, including questions about viral evolution, biological fitness, and transmissibility. But some facts are strikingly clear. Influenza B mutants with reduced sensitivity to neuraminidase inhibitors are circulating, and these viruses can cause infections with no difference in duration of symptoms, level of viral shedding, or clinical outcome. Contrary to what had been hoped until now, some resistant variants are vigorous pathogens. Whether these viruses arise by spontaneous mutation or through drug selection, or whether they are transmitted within families or acquired from the community, the resistant variants may be here to stay. In light of the recent observation that oseltamivir may be less effective against influenza B than against influenza A, an important concern is whether suboptimal dos ing for these viruses will lead to increased selection of viruses with high-level resistance.?

“Influenza viruses evolve rapidly and nimbly, which compels ongoing investigation of antiviral therapies that use alternative mechanisms of action and target different points in the viral life cycle. The emergence of drug-resistant influenza B should draw attention to the importance of continual monitoring of strains over time and to the need for frequent rethinking of policies for use of antiviral drugs. While the news about resistance is not good and certainly calls into question some of the current assumptions about drug-resistant viruses, an effective response to this news can help contend with the new challenges of influenza.?

(JAMA. 2007;297:1492-1494. Available pre-embargo to the media at www.jamamedia.org)

Editor’s Note: Please see the editorial for additional information, including financial disclosures, funding and support, etc.
'"/>

Source:JAMA and Archives Journals


Related biology news :

1. Novel Asthma Study Shows Multiple Genetic Input Required; Single-gene Solution Shot Down
2. Emory Study Tests Bone Marrow Stem Cells to Improve Circulation in Legs
3. UCLA Study Shows One-Third of Drug Ads in Medical Journals Do Not Contain References Supporting Medical Claims
4. Study Demonstrates Gene Expression Microarrays are Comparable and Reproducible
5. Study Links Ebola Outbreaks To Animal Carcasses
6. Breakthrough Microarray-based Technology for the Study of Cancer
7. NYU Study Reveals How Brains Immune System Fights Viral Encephalitis
8. Study finds more than one-third of human genome regulated by RNA
9. Leukemia Drug Breakthrough Study In New England Journal Of Medicine
10. Study identifies predictors of HIV drug resistance in patients beginning triple therapy
11. New Study from Affymetrix Laboratories Points to Changing View of How Genome Works

Post Your Comments:
*Name:
*Comment:
*Email:


(Date:2/2/2017)... 2, 2017  EyeLock LLC, a market leader of ... paper " What You Should Know About Biometrics in ... user authenticity is a growing concern. In traditional schemes, ... However, traditional authentication schemes such as username/password suffer from ... authentication offers an elegant solution to the problem of ...
(Date:2/1/2017)... IDTechEx Research, a leading provider of independent market research, ... a new report, Sensors for Robotics: Technologies, Markets and Forecasts ... ... Revenues ... "Sensors for Robotics: Technologies, Markets and Forecasts 2017-2027: Machine vision, force ...
(Date:1/30/2017)... SAN FRANCISCO , Jan. 30, 2017   ... of the fastest growing genetic information companies, today announced ... 2016 financial results and provide 2017 guidance on Monday, ... a conference call that day at 4:45 p.m. Eastern ... call, Invitae,s management team will briefly review financial results, ...
Breaking Biology News(10 mins):
(Date:2/24/2017)... Biologic Products, Inc. (NASDAQ: CBPO) ("China Biologic" or the "Company"), ... announced its financial results for the fourth quarter and fiscal ... Highlights Total sales in the fourth ... increased by 13.6% in USD terms to $77.6 million from ... Gross profit increased by 13.3% to $46.8 million from ...
(Date:2/23/2017)... Financial ... data, unaudited)Three Months Ended December 31,Twelve Months Ended December ... $           300$ ... Net Product Revenue 3539(10)%9498(4)%Kuvan Net ... Revenue  756025%297303(2)%Vimizim Net Product Revenue ...
(Date:2/23/2017)... -- In Atlanta, it seems everyone has a chance to express ... an expressive and dynamic community unlike any other. The businesses ... it. With their newest salon in ... carry on that tradition with a unique, fresh approach to ... is the newest of 13 nationwide locations, each of them ...
(Date:2/23/2017)... ... February 23, 2017 , ... Baltimore ... multiple immunoassay-based threat detection technologies by researchers from the Pacific National Northwest ... detection technology was found to have the best level of detection (LOD) ...
Breaking Biology Technology: