The document discusses influenza (flu), a highly contagious viral infection that often causes fever and body aches. It spreads through airborne droplets when infected people cough, sneeze or talk. Common symptoms include runny nose, sore throat, cough, fever, body aches and fatigue. While antibiotics do not treat viruses like the flu, vaccination and rest can help prevent and treat the illness. Those at higher risk include young children, older adults, pregnant women and those with weak immune systems. There are different types of flu viruses that occasionally spread between animals and humans.