Irish-based Greencore is one of the largest manufacturer of pre-packed sandwiches in the UK, suppling most of the country's big retailers, including Marks & Spencer, Waitrose, Sainsbury’s and Tesco.
A spokeswoman for Northamptonshire County Council said 79 people returned positive NHS tests and a further 213 tested positive through Greencore’s private testing.
The company, which was set up following the privatisation of Irish Sugar, took the decision to test workers as a result of a rise in cases in the the area.
In a statement, Greencore said: “As a result of the rising number of Covid-19 cases in the Northampton area, we took the decision to start proactively testing all of the colleagues at our Northampton site."
The company added: “In each case we have immediately conducted contact tracing and instructed potentially affected colleagues to self-isolate.
“All of Greencore’s sites have wide-ranging social distancing measures, stringent hygiene procedures and regular temperature checking in place, and we are doing everything that we can to keep our people safe."
Lucy Wightman, director of public health at Northamptonshire County Council, said employees have been asked to “act now” after the number of confirmed cases in the town increased from 66 in the week ending August 2nd to 85 for the week ending August 9th.
Ms Wightman said: “It is evident that Greencore has highly effective measures in place and they continue to work extremely hard to exceed the requirements needed to be Covid-19 secure within the workplace."
In a 2017 article, The Guardian claimed Greencore was the largest sandwich maker in the world, operating eight facilities in the UK.
