serves to clean them. so there's really a lot -- a lot of virus here. >> in 2011 when the pasteur institute started monitoring the wash water, 18% of the water samples were positive for h5n1. four years later, 66% of samples were positive. >> we know that bird flu is very, very deadly. and we know swine flu spreads very quickly. what we worry about is that if those two reassort and then we could have a new strain that could spread literally as quickly as the swine flu did but have the mortality rate of bird flu. that's the big fear. that we have now literally created a petri dish we all worried about and both those viruses are sitting in there at the same time. >> pandemics are one of the