Anti-viral resistance in 2009 A/H1N1 flu - historical compilation of news

[Shiloh]

Re: Tamiflu resistance in A/H1N1 flu - historical compilation of news

Re: Tamiflu resistance in A/H1N1 flu - historical compilation of news

Source: http://focustaiwan.tw/ShowNews/WebNews_Detail.aspx?Type=aLIV&ID=201103080022

Health department reports 3 strains of Tamiflu-resistant H1N1 virus
2011/03/08 19:15:21

Taipei, March 8 (CNA) The Centers for Disease Control (CDC) confirmed Tuesday the discovery of three H1N1 strains that are resistant to the most commonly prescribed antiviral drug Tamiflu.

Three patients infected with the Tamiflu-resistant strains were admitted to hospital in late January and early February this year, said Shih Wen-yi, the CDC's deputy director-general.

However, "there are no signs of these strains spreading into the wider community, " he said, adding that none of the 133 samples taken from people who had contact with the patients had tested positive for resistance to Tamiflu.

The patients, aged 13, 35, and 51, were reported to have low immune systems caused by asthma, a bone marrow transplant, and lupus, respectively, he said.

Tamilfu, which is the generic drug oseltamivir, normally kicks in one to two days after it is started, but in the three cases, they either did not respond or responded poorly, Shih said.

However, the three H1N1 strains, along with another eight that were detected in 2009, can be treated with zanamivir, a prescription drug used mostly against influenza A and B, he said...

 

[Ronan Kelly]

Tamiflu resistance in A/H1N1 flu - historical compilation of news

Tamiflu resistance in A/H1N1 flu - historical compilation of news

NEWS RELEASE: SIXTH ANTI-VIRAL RESISTANT FLU CASE IDENTIFIED
Delaware?s Division of Public Health (DPH) laboratory results confirm a sixth Delaware case of antiviral-resistant influenza for the 2010 ? 2011 flu season. A 55 year-old woman from Kent County was infected with an influenza strain found to be resistant to oseltamivir, the preferred treatment antiviral medication used to treat confirmed cases of influenza.

There is no reason to change treatment approaches at this time. There are four influenza antiviral medications approved for use in the United States: oseltamivir (brand name Tamiflu), zanamivir (brand name Relenza), amantadine (Symmetrel, generic) and rimantadine (Flumadine, generic).

Although it is late in the flu season, as always DPH recommends the following precautions for both the public and clinicians:
? Get vaccinated against the flu.

? Wash your hands frequently with soap and warm water or use an alcohol-based hand sanitizer.

? Cover your cough/sneeze with a tissue, or cough/sneeze into your inner elbow and not into your hands.

? If you are sick, stay home for at least 24 hours after your fever goes away. This means no fever for at least 24 hours after you have stopped taking any fever-reducing medication. Employers are encouraged to be flexible with their employees on the issue of staying home when ill.
Stay informed about the latest developments on the flu by visiting www.flu.delaware.gov

Delaware Health and Social Services is committed to improving the quality of the lives of Delaware?s citizens by promoting health and well-being, fostering self-sufficiency, and protecting vulnerable populations.
http://www.wgmd.com/?p=22447

 

[Ronan Kelly]

Re: Anti-viral resistance in 2009 A/H1N1 flu - historical compilation of news

Swine flu starting to show resistance to drugs
10 Jun 2011 10:14

Source: reuters // Reuters


* Reduced sensitivity seen to Roche's Tamiflu, GSK's Relenza

* Affects 30 pct N.Australia samples, 10 pct from Singapore


LONDON, June 10 (Reuters) - A novel variant of swine flu has emerged in Asia with a genetic adaptation giving some resistance to Roche's Tamiflu and GlaxoSmithKline's Relenza, the two mainstay drugs used to tackle the disease.

Researchers said more than 30 percent of H1N1 swine flu infection samples from northern Australia, and more than 10 percent of those in Singapore, collected during the early months of 2011 had mildly reduced sensitivity to the two drugs.

There was no significant reduction in sensitivity to peramivir, an experimental flu drug from BioCryst Pharmaceuticals <BCRX.O>.

...

http://www.trust.org/alertnet/news/swine-flu-starting-to-show-resistance-to-drugs

 

[Giuseppe]

Re: Anti-viral resistance in 2009 A/H1N1 flu - historical compilation of news

The Eurosurveillance paper is available at:

Increased detection in Australia and Singapore of a novel influenza A(H1N1)2009 variant with reduced oseltamivir and zanamivir sensitivity due to a S247N neuraminidase mutation

Eurosurveillance website: full free text, http://www.eurosurveillance.org/ViewArticle.aspx?ArticleId=19884

Flutrackers.com, abstract: http://www.flutrackers.com/forum/showpost.php?p=411615&postcount=1

 

[Treyfish]

Re: Anti-viral resistance in 2009 A/H1N1 flu - historical compilation of news

Drug resistant, the H1N1 virus mutated in Singapore and Australia



June 12, 2011 04:04
Singapore - Researchers to the World Health Organization (WHO) states that the H1N1 flu virus that has swept the world in 2009 has been mutated, and now appeared in Singapore and Australia.

New H1N1 virus has a stronger genetic so it is more resistant to drugs such as Tamiflu and Relenza, which is believed to be the mainstay drugs to cope with the H1N1 virus.

Page channelnewsasia.com states, WHO hypothesis was obtained after the researchers found that given the suspect bird flu drug Tamiflu and Relenza was no longer able to cope with the virus attack.

The researchers said the H1N1 virus resistant to Tamiflu, and patients with weak immune eventually died.

But laboratory tests showed the drug was still effective Peravimir flu virus H1N1 overcome.

WHO also reveal new variants in other parts of Asia Pacific. It is feared that if the new form will trigger the spread of swine flu H1N1 virus resistant to the drug would be more serious.
:tiphat:http://www.primaironline.com/berita...rus-h1n1-bermutasi-di-singapura-dan-australia

 

[mixin]

Re: Anti-viral resistance in 2009 A/H1N1 flu - historical compilation of news

01 June 2011 ‐‐ For this reporting period (18 May ‐ 01 June 2011), 16 new cases of influenza A (H1N1) 2009 viruses carrying the H275Y substitution have been reported. It brings the cumulative total to 508 so far.

Comparison of the WHO updates in May 2010 and June 2011; notice that they changed the a couple of the colors in the chart.







http://www.who.int/csr/disease/influenza/update/en/index.html

 

[sharon sanders]

Anti-viral resistance in 2009 A/H1N1 flu - historical compilation of news

It appears that 19 of the 29 people in this study with oseltamivir resistant A/H1N1pdm09 had no known links to each other. i.e. Possible community spread of oseltamivir resistant A/H1N1pdm09.

Community Transmission of Oseltamivir-Resistant A(H1N1)pdm09 Influenza
N Engl J Med 2011; 365:2541-2542
December 29, 2011


snip

A fluorescence-based neuraminidase inhibition assay5 of the H275Y isolates showed that the IC50 value (the concentration of drug required to inhibit neuraminidase activity by 50%) was 513 times higher for oseltamivir and 80 times higher for peramivir than the IC50 values associated with wild-type strains.

snip

Hospital records and interviews with patients and general practitioners revealed that only 1 of the 29 patients with resistant influenza had received oseltamivir before the influenza specimen collection

snip

Four households had 2 affected patients each, and 2 other patients shared a short car journey. The remaining patients had no known epidemiologic link with the other patients with oseltamivir-resistant influenza described here.

http://www.nejm.org/doi/full/10.1056/NEJMc1111078