Why do colds so often start in the throat and work their way up to the nose? © Getty Images

Why do colds so often start in the throat and work their way up to the nose?

It's a matter of ease of infection - and the throat is an appealing environment for viruses to start colonising.

Asked by: Anonymous

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It’s a matter of ease of infection. The throat has a big area of mucous membrane available for colonisation by viruses, and the nose is well protected against invasion by small numbers. Once a large colony has established itself in the throat, though, rafts can break free to overcome the nose’s defences by sheer weight of numbers.


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