United Press International: U.S. government scientists are disputing studies that predict climate change might expand the scope of human infectious diseases. Kevin Lafferty of the U.S. Geological Survey and colleagues suggest that instead of an expansion of the global range of diseases, global warming might cause a poleward shift in areas suitable for diseases as higher latitudes become warmer and regions near the equator become too hot. Lafferty says the newly suitable areas for diseases will tend to be …