A former health worker who had been diagnosed with Hepatitis C is now known to have transmitted the virus to two other patients.
Aneurin Bevan Health Board launched an exercise in September after it was revealed that the worker, who was involved in obstetrics and gynaecology, had unknowingly passed on the virus to two people between 1984 and 2003.
They worked predominantly at Caerphilly District Miners' Hospital, but also for a short time at the old East Glamorgan Hospital in ChurchVillage near Pontypridd and Wrexham Maelor Hospital.
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