that does not require bsl 4 laboratory facilities in order to run experiments. to people of any ideas about that? dr. peters? >> there's a species of ebola called reston which is -- not to be pathogenic for us humans and can be downgraded from 4. in addition to that some colleagues have produced and ebola virus by genetic engineering that lacks the genes to ward off interferons which ebola has in quantity, and is probably not pathogenic, although i can't imagine any institutional review board giving permission to use it. >> other ideas about that? >> there are very -- there is pseudo-type of viruses that could potentially be used. you do always get into the question of, you do those experiments and then say that but is that really, doesn't react, act the same as the real virus? that will be another idea. >> from the point of view of doing studies for ppd, we would like a circuit that floresta's. -- florescent. >> some of the circuits that dbas using with bacteria would not be appropriate at all come in terms of size and other characteristics. >> part of the prob