Even the sight of an infection can trigger an immune response

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Jul 30th 2025|3 min read

THE HUMAN immune system is full of surprises. Though it has long been known that the body’s internal defences spring into action when an infection-causing intruder—such as a bacterium or virus—is detected, a new study published in Nature Neuroscience suggests that the mere sight of an infection may be enough to kick the immune system into gear. The findings could reframe scientists’ understanding of this most complex of biological systems and aid the development of treatments for immune disorders.