No new human cases of avian influenza have been reported, and poultry infections are low so far in March. But infections in cats are continuing, and new research is raising concerns about the virus

Where does our avian flu epidemic come from? Commercial, large-scale poultry farming and migrating birds squeezed into smaller and smaller areas as people destroy wetlands, experts say. And after birds pass it to each other,

Scientists are sounding alarms about a genetic mutation that was recently identified in four dairy cow herds, nearly one year after H5N1 bird flu was first reported in Texas dairy cattle. The change is one that researchers have dreaded finding because it is associated with increased mammal-to-mammal transmission and disease severity.