Public Health England has said the risk of cat owners contracting tuberculosis is "very low" after two people developed the disease after coming into contact with a cat.
Professor Dilys Morgan told ITV News, "Something strange has happened in this instance".
"We don't know exactly what's happened but I don't think that we can read too much into it, that it is an increasing trend," she added.
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In a rallying call at the Democratic National Convention, the former US president said Hillary is 'the best darn change-maker I ever met'.
Satoshi Uematsu, 26, was sent to the Yokohama District Public Prosecutors Office in Kanagawa prefecture.
West Yorkshire Police confirmed a 32-year-old woman was taken into custody in connection with the alleged threats.