Science In Action

Scientists have found that just one mutation in the current H5N1 virus in cattle can switch its preference from avian to human receptors. Jim Paulson and colleagues at the Scripps Institute did not use the whole virus to investigate this, but proteins from one of the Texas farm workers found to be infected. It suggests the bovine H5N1 virus has already evolved subtly. Meanwhile, Richard Webby of St. Jude Children's Research Hospital in Memphis helps us catch up on the latest known about the case of the Canadian teenager taken seriously ill a month ago with a different variant of avian H5N1. A debate has been rumbling this last year about the extent of ocean warming by, perhaps paradoxically, the reduction of particulate pollution from the fuel used by ships. The idea is that the small particles of sulphates and nitrates in the soot from funnels actually formed clouds over shipping lanes out at sea. This in turn sheltered the oceans to some extent from solar radiation, thus making latter decades of the 20th