Final answer:
The body fights a viral infection by raising the body temperature to create a fever, which slows down viral replication and stimulates white blood cell production.
Step-by-step explanation:
The body's natural defense when invaded by a virus involves raising the body temperature, a response known as a fever. The normal body temperature is 98.6°F (37°C), which is the optimal temperature for most pathogens, including viruses, to reproduce. A fever inhibits viral replication by elevating the body temperature above this optimal range, thus slowing down the infection process. Additionally, a fever stimulates the immune system to produce more white blood cells, enhancing the body's ability to fight off the viral infection.