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H5N1 Anti-virals
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>>The at-risk group of tigers was re-treated with an anti-viral drug
(oseltamivir), administered twice daily (morning and evening) in a piece of meat for 5 consecutive days (less than 60 kg body weight: 75
mg/animal/dose; 60 kg body weight and above: 150 mg/animal/dose).<<
It would seem that based on the short time period (3 days) between symptoms and death, most of the tigers were treated before they showed symptoms. Yet in spite of treating the tigers twice a day instead of once, and double the recommended dosage for each treatment, most if not all of the at risk tigers had to be euthanized (n=102) or died (n=45).
In vitro data on H5N1 viruses from Vietnam and Thailand also indicated that a relatively high dose of Tamiflu was needed to block growth of the virus on MDCK cells. Thus, it would seem that limited stockpiles of Tamiflu would have a modest effect at best in slowing a pandemic caused by an H5N1 virus similar to the virus that is causing a 70% case fatality rate in Vietnam and Thailand. The virus has also been shown to be resistant to Amantadine and Ramantadine because of two polymorphisms in the M2 gene.