It's because we aren't comparing the interest *HIV*. (Um.. think of those asterisks as wildcards, not marks of emphasis.) Just because no one has selected your exact character string doesn't meant that no one else has that actual interest. This is one of the great flaws of the LJ interest-finder. If you could search on wildcards, you could find more people who share the actual interest, and not just those who have happened to type inthe same string of characters.
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K.
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I'm shocked that no one besides me picked up "female soloists". Ah me.