"Jennifer McKimm-Breschkin told a major international influenza conference that testing conducted in her laboratory showed the viruses from Indonesia were 20 to 30 times less susceptible to the drug as compared to H5N1 viruses that circulated in Cambodia a couple of years ago."
"She said the mutations that made the viruses less vulnerable to oseltamivir developed spontaneously in nature and were not a consequence of poor use of the drug."
"McKimm-Breschkin said the findings highlight the advisability of governments stockpiling both Tamiflu and zanamivir (Relenza), so as not to get caught out if resistance to one or the other develops."
""One can't only look at the susceptibility. One also has to look at the fitness of the virus, the pathogenicity (virulence) of the virus," said Dr. David Reddy, pandemic task force leader for Hoffman-La Roche, the maker of Tamiflu."
"Scientists have wondered if the molecular variations between the clades and sub-clades translate into differences in attack rates or disease severity in people who become infected, looking for ways to explain why, for example, 80 of 100 cases in Indonesia have died while in Egypt only 15 of 36 cases have died. (Viruses in Egypt belong to a different subgrouping of clade 2 than those in Indonesia)."
"A research network of Southeast Asian clinicians, organized by the WHO and with support from Roche, is starting to test whether higher doses of oseltamivir, over a longer period, would be more effective in treating H5N1."
