Amid rising respiratory illnesses, a CDC report reveals undetected bird flu cases in US veterinarians. The spread, shown through antibody tests, indicates infections occurring beyond known zones. Experimental confirmation of H5N1 transmission through cow milk prompts officials to urge all states to join the national milk testing program.

Sonya Stokes, an emergency room physician in the San Francisco Bay Area, braces herself for a daily deluge of patients sick with coughs, soreness, fevers, vomiting, and other flu-like symptoms.