Millions of Americans will be grilling over the Fourth of July weekend. UDSA Food Safety Specialist C.C. Williamson says it's vitally important to use a meat thermometer when you're grilling burgers. She warns that burgers that appear to be fully cooked often end up making people sick. One in six Americans get food poisoning every year, and about three-thousand die annually. For more tips on safe grilling, log on to FoodSafety.gov.