infection

A fever is not an illness but a weapon—your immune system's coordinated response to infection that raises your body's set-point temperature. When pathogens invade, immune cells release signaling molecules called pyrogens that travel to the brain and reset the temperature thermostat from 37°C to 39°C or higher. This increase is controlled and purposeful: the higher temperature slows bacterial growth, accelerates immune cell activity, and enhances antiviral proteins. Understanding fever as an adaptive defense explains why suppressing it indiscriminately can sometimes hinder recovery, yet also reveals when dangerous fevers require immediate treatment.

How germ theory revealed that microorganisms cause disease revolutionizing medicine and public health

Antibiotics transformed medicine. Used right, they cure deadly infections in days. Used wrong, they're driving one of the biggest health threats we face. Here's how they really work.

Viruses and bacteria both cause infections and both are too small to see, yet they differ in size, structure, reproduction, and treatment. Here is how to tell them apart.