October 11, 2005
Washington: Governments around the world are stockpiling antiviral drugs and some companies are trying to speed up vaccine production, but these measures will do little to counter a flu pandemic, an expert has cautioned. Michael Osterholm, an infectious diseases expert who has been studying the risk of pandemic flu for decades and is a US government adviser, said yesterday governments should be preparing to cope with the pandemic instead of relying on vaccines and drugs to control it. If the H5N1 avian flu began to easily infect humans, it would move too quickly for drugs and vaccines to be of much use. Experts say it is mutating steadily and fear it will eventually acquire the changes it needs to spread easily from person to person. If it does, it will sweep around the world in months or even weeks and could kill millions of people.
There are two drugs in the class - Roche and Gilead's Tamiflu and GlaxoSmithKline's Relenza. They work to reduce the severity of annual influenza and may prevent infection if used at the right time. Tests suggest they also work against H5N1, but no one knows how well. The US has enough courses of Tamiflu to treat about 2.3 million people. Another 2 million treatment courses are on order and will arrive by the end of the year. But about 90 million people would need the drug in the event of a flu pandemic, University of Virginia flu expert Frederick Hayden told a meeting on Saturday. At current capacity, it would take about 10 years to produce enough Tamiflu to treat 20% of the world's population, Hayden said.
And vaccines are not an answer yet and will not be for years. There is an experimental vaccine against H5N1 but there are only a few thousand doses of it. A study published last week showed that the H1N1 virus that caused the 1918 flu pandemic - which killed at least 40 million people globally - was a purely avian virus that acquired a few mutations that gave it the ability to infect people easily. H5N1 is mutating in a similar way and experts believe it is only a matter of time before it, too, infects people easily. - Reuters