VIENNA, Austria - Three cats have tested positive for the deadly strain of bird flu in Austria's first reported case of the disease spreading to an animal other than a bird, state authorities said Monday. The sick cats were among 170 living at an animal shelter where the disease was detected in chickens last month, authorities said. The World Health Organization called bird flu a greater global challenge than any previous infectious disease, costing global agriculture more than $10 billion and affecting the livelihoods of 300 million farmers. [snip] Dr. Margaret Chan, who is spearheading WHO's efforts against bird flu,...