Health Fusion: Heat waves can kill. Know how to keep babies, adults and older people safe when temperatures spike

<p>Your body adjusts to hot weather slowly. So when heat waves hit, you need to know how to hydrate and stay cool to avoid heat-related illness. This is especially true for babies and older adults. In this episode of NewsMD's "Health Fusion," Viv Williams gets tips from an emergency medicine doctor about how to stay healthy in extreme heat.</p>