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Immune System

In Focus

The Immune System

From fending off the common cold to attacking cancer cells, the immune system is an incredibly complicated and crucial part of our survival.

Each time it mounts a response, the immune system must quickly and carefully orchestrate communication across vast numbers of cells and molecules.

Explore how the immune system protects us
We can completely reimagine how our cities, hospitals, and families prepare for and deal with cold and flu season.”

Bill Hanage

Harvard T.H. Chan School of Public Health

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With COVID added to the mix of viruses that typically circulate every year—including influenza, RSV, and other respiratory viruses—experts say “sick season” is likely to be worse, and longer, going forward.

Learn more about these viruses:

Boosting what we know

Scholars at Harvard are working to discover even more secrets of the immune system, from how it protects us to how it can be strengthened.

Review a first-of-its-kind Immune Dictionary

This might be a golden age for human immunology.”
Shiv Pillai
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Scientists are working to better understand early-life immunity

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The beneficial effects of exercise may be driven by the immune system

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Studies of deep-sea microbes showed that immunity can cross evolutionary distances

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Scientists are investigating how the immune system goes awry

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Research suggests that the thymus plays a vital role in immune health

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Researchers discovered that the gut microbiome is critical in the immune system's development

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How can you improve your immune system?

Our immune systems do a remarkable job of defending against infection, but sometimes they need some support.

Explore ways to fight off illness this winter

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How does gut health impact our immunity?

A Harvard study found an intricate interplay between gut microbes, food, and immunity.

Learn how your gut can impact your immunity

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What can we do to keep our children healthy?

A Harvard medical school professor offers advice on how to help boost your child’s immunity.

Read about ways to protect children against illness

Learning from the past

Looking to the future