(H1N1) became resistant to both oseltamivir and amantadine in a short span of 1 month. Oseltamivir-resistant A/Brisbane/59/2007-like clade 2B virus that had reassorted with A/Hong Kong/2652/2006-like clade 2C virus had apparently spread in the community and to other regions of the world. The possibility of reassortment with pandemic (H1N1) 2009 virus is a major concern. Resistance to oseltamivi...

A liquid chromatography-tandem mass spectrometry method for the analysis of seven antiviral drugs, zanamivir, ribavirin, oseltamivir, oseltamivir carboxylate, amantadine, rimantadine and arbidol, in poultry muscle is reported. The antiviral drugs were extracted from the homogenized poultry muscle sample using methanol. The extract was purified using tandem solid-phase extraction combining a cat...

In Norway in January 2008, unprecedented levels of oseltamivir resistance were found in 12 of 16 influenza viruses A (H1N1) tested. To investigate the epidemiologic and clinical characteristics of these viruses, we used sequence analysis to test all available subtype H1N1 viruses from the 2007-08 season for resistance. Questionnaires from physicians provided information on predisposing diseases...

BACKGROUND Current oseltamivir prophylactic regimens may not be as effective against highly pathogenic H5N1 influenza viruses as they are against less pathogenic strains. An optimal regimen is urgently needed. METHODS Ferrets were given the neuraminidase inhibitor oseltamivir orally for 10 days (5 or 10 mg/kg once daily or 2.5 or 5 mg/kg twice daily). Prophylaxis was initiated 1 day before in...

Anti-viral chemotherapy plays an important part in treating and preventing influenza illness. However, its effectiveness in severe infections can be debated and a reoccurring problem is the emergence of resistant virus. Passive immunisation has for a long time been and is still used for prophylaxis and treatment of a number of infectious diseases. In this experimental study anti-influenza antib...

AIMS Pandemics impose large demands on the health care system. The supply of appropriate chemotherapeutic agents, namely oseltamivir solution, presented a serious challenge in the recent influenza pandemic. This study reports on the rational series of pharmacotechnical steps that were followed to appropriately handle bulk oseltamivir powder to meet the increased demand. METHODS During a six-w...

BACKGROUND It is unclear if higher-dose oseltamivir provides benefit beyond the standard dose in influenza patients who require hospitalization. METHODS A prospective intervention study was performed in 2 acute care general hospitals in Hong Kong over 4 seasonal peaks (2010-2012). Adults (≥18 years) with laboratory-confirmed influenza (85 A/H3N2, 34 A/H1N1pdm09, 36 B) infections who presented...

BACKGROUND Anti-viral treatment has been used to treat severe or progressive illness due to pandemic H1N1 2009. A main cause of severe illness in pandemic H1N1 2009 is viral pneumonia; however, it is unclear how effective antiviral treatment is against pneumonia when administered >48 hours after symptom onset. Therefore, we aimed to determine how time from symptom onset to antiviral administrat...

Influenza is a highly contagious and debilitating disease that imposes an excess burden of complications and mortality. Antiviral therapy is the primary intervention for treatment and post-exposure prophylaxis (PEP) of influenza. Amantadine and rimantadine are members of the M2 class of antiviral agents and are moderately effective in influenza management. However, their utility is compromised ...

To assess adherence to real-time changes in guidelines for influenza diagnosis and use of oseltamivir during the 2009 influenza A(H1N1) pandemic, we reviewed medical records of patients with confirmed or suspected influenza-like illness (ILI) and those with no viral testing in a large Los Angeles (California, USA) hospital. Of 882 tested patients, 178 had results positive for influenza; 136 of ...