Hi,
again reading a book

including this sentence:
Nobody knew that I had the negative.
Would it be possible to say ".. that I have the negative" if it is still true? Because my grammar book says that if the original speaker´s present and future are still present and future - a reporter can choose whether to keep the original tense or change it.
But maybe it is so that the whole story is in the past, so it is not possible to use present tense.
Thanks a lot!
Hanka