During the recent Covid-19 pandemic, the rate of serious illness and death was jarringly high in older populations. Why? Weakening immune systems — as we age, we become more vulnerable to infections, ...

Every day, your immune system performs a delicate balancing act, defending you from thousands of pathogens that cause disease while sparing your body’s own healthy cells. This careful equilibrium is ...

Tuberculosis, caused by the bacterium Mycobacterium tuberculosis (Mtb) kills upwards of 1.6 million people a year, making it one of the leading causes of death by an infectious agent worldwide -- and ...

The human body’s defensive lineup is impressive—from made-to-order antibodies to natural-born killers. Here’s how it wards off sickness in every season. When pathogens invade our bodies—in the form of ...