Hello! My name is Rolf Ypma. I study avian influenza,
a disease carried by many wild birds. Although it usually doesn't cause severe
illness in wild birds,
the virus can be transferred to poultry, to whom it's highly infectious and lethal.
The virus can kill humans as well, luckily the probability of getting
infected is extremely low.
Still, it's obviously important that any outbreak of the virus is detected and
stopped as quickly as possible,
to halt further spread. The only viable way we currently have of stopping an
outbreak is preemptive culling of healthy animals.
For example, in a large epidemic in the Netherlands in 2003,
30 million birds had to be culled. If we want to stop the virus more efficiently
we'll need a better understanding of how it spreads. One possibility is that
virus particles are blown to new farms by wind.
This hypothesis can be tested from the 2003 outbreak by reconstructing the
transmissions between farms of the virus.
Such a reconstruction is possible using the viral DNA we obtained from all
infected farms.
My part of the study was to use this DNA to calculate viral movements.
I did this by formulating mathematical equations that describe both how the
virus transmits,
and how it mutates. We then compared the transmissions between farms with the
wind direction at time of transmissions.
We found that the two were suspiciously often in the same direction,
which led to our conclusion that wind plays a role in spreading the disease.
This information can be used to halt the virus,
for example by installing special filters that stop virus particles from
getting through.