 Moderna is getting $176 million from the U.S. government to develop a messenger RNA-based bird flu vaccine for humans. This is health officials' step-up efforts in response to a growing outbreak among farm animals. The H5N1 bird flu has been detected on poultry farms in almost every U.S. state and in dairy herds in a dozen states, making it the biggest outbreak in recent years. Free dairy workers have also been infected because of exposure to cattle.