No. It is an incorrect use of "that" to join two ideas. You can say, for example: You rarely miss work because of illness.
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AnonymousYou are rarely so sick that you miss work.You can correct it as shown above.
CalifJimAnonymousYou are rarely so sick that you miss work.You can correct it as shown above.Though I don't know for certain, my feeling is that this was probably not meant.
CalifJimThough I don't know for certain, my feeling is that the OP accidentally omitted "so".So I see.