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in reply to Re: The plural of "athlete's foot" is...
in thread The plural of "athlete's foot" is...

Yes, this is what I was thinking too.
Since its a mass noun (massive noun?), it would need a quantifier word such as "cases" or "problems" to refer to multiple instances. So you would say "There are three cases of athlete's foot".

However, you can also say "There are several itchy athlete's foots available". I think there's some kind of rule in English where you can just add an "s" or "es" to any noun to make it plural.