A Scots call centre worker has told how at least four people have tested positive for Covid-19 after an outbreak at a contact tracing centre.The 19-year-old was employed at the Sitel building in Maxim Park, near Motherwell, alongside as many as 200 other people before it was locked down by management.The teenager, who worked for Virgin Media on the upper floor of the building, discovered there was a cluster of cases after arriving for work on Saturday.A number of workers from the contact trace