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Can my immune system fight disease without me realising? © Getty Images

Can my immune system fight disease without me realising?

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As in the song Every Breath You Take, your immune system is fighting off harmful bacteria with each breath, you just don’t always feel it.

Asked by: Jenny Price, Weston-super-Mare


With each new breath, you take in about 50 potentially harmful bacteria. Virtually all of these are promptly destroyed by your immune system without you feeling a thing. But some bacteria and viruses can successfully infiltrate the body and lie dormant without causing any symptoms for many years until they suddenly flare up.

Chlamydia infections, for example, show no symptoms for 50-70 per cent of women, because they lurk beneath the radar of the immune system. Any disease that your immune system does pick up, however, triggers swelling, inflammation and fever as the disease is fought, so that’s something you will definitely notice.

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luis villazon
Luis VillazonQ&A expert

Luis trained as a zoologist, but now works as a science and technology educator. In his spare time he builds 3D-printed robots, in the hope that he will be spared when the revolution inevitably comes.


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