The results of a post-mortem examination on a man who had measles when he died were "inconclusive", Swansea Coroner's Office has said.
An inquest into Gareth Colfer-Williams' death is due to be opened next Tuesday.
Public Health Wales said last week that initial tests showed he had measles when he died, but that it was not confirmed if measles was the cause of his death.
83 people have now been hospitalised since the outbreak started, but Mr Colfer-Williams is the only suspected death.
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