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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Figures suggest that more than 11 million homes, or 42%, are in credit to their energy company.
Undivided, which represents more than 4 million young people, has set out its top issues in an open letter to political leaders.
John Wombell, 58, was jailed for eight weeks after admitting making the grossly offensive call to the Broxtowe MP's office last November.