for National Geographic News
Facing the potential threat of a global bird flu pandemic, many governments are stockpiling antiviral drugs such as Tamiflu. These drugs are known to help infected patients recover, and they can slow the spread of a virus if they are given to people who aren't infected.
But research shows that widespread use of such medications can promote virus mutation, increasing the probability of new strains developing and making it harder to stamp out a virus in the long run.
This provides a serious dilemma: Should antiviral drugs be given out sparingly, leaving many people exposed and in danger? Or should the tablets be dispensed widely, despite the enhanced risk of resistant strains of flu emerging?
Roland Regoes and Sebastian Bonhoeffer of the Swiss Federal Institute of Technology Zurich are helping to answer these kinds of questions using mathematical models of infectious disease.
By simplifying the situation and considering a small enclosed population, such as five hundred people in a boarding school, they are able to focus on how a virus evolves.
Specifically, the researchers have been studying the effect of the drugs during a pandemic.
(See maps of a simulated flu outbreak in the United States, showing rates of infection if antiviral drugs are administered and if they are not.)
"During a pandemic we will have a tremendous problem developing a vaccine, so antiviral drugs will be our first line of defense," Bonhoeffer said.
However, dispensing the antiviral drugs too freely could also make the problem worse.
No Data From the Past
Antiviral drugs are a relatively new development. The last time there was a flu pandemic, these drugs didn't exist and people just had to suffer through the virus.
If a pandemic strikes again, antivirals are likely to be a key weapon, but it is vital that they are used optimally, experts warn.
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