(<a href=www.newscientist.com target=_blank>New Scientist) A scientist funded by the US government has deliberately created an extremely deadly form of mousepox, a relative of the smallpox virus, through genetic engineering. The new virus kills all mice even if they have been given antiviral drugs as well as a vaccine that would normally protect them. The work has not stopped there. The cowpox virus, which infects a range of animals including humans, has been genetically altered in a similar way. The new virus, which is about to be tested on animals, should be lethal only to mice, Mark Buller of the University of St Louis told New Scientist. He says his work is necessary to explore what bioterrorists might do.