Thermal imaging cameras were installed at the Iceland distribution warehouse and deep cleans introduced at the Iceland distribution warehouse at the centre of a mini-outbreak of coronavirus.

So far, almost 80 people at the XPO Logistics warehouse in Penzance Drive have tested positive for the virus. A temporary testing unit was sent to the site last week and more than 500 staff members tested.

Public health officials say the infection rate has slowed dramatically over recent days, with just one new case reported on Tuesday. Swindon council said there had been 77 confirmed cases as of Wednesday evening.

XPO managers wrote to the Swindon plant’s 750 staff this week, telling them of additional measures put in place since the outbreak.

In the letter, obtained by the Adver, site manager Phil Chapman said the company had already introduced thermal cameras following the lockdown in March to identify anyone entering the plant with a high temperature. 16-hour cleaning rotas, face masks and gloves were among the other safety measures introduced in the spring.

Since the outbreak the depot was now being cleaned round the clock, Mr Chapman said. “This extra time is dedicated to specialised ‘contact point’ cleaning, designed to ensure that the various touchpoints around the workplace are kept scrupulously clean, reducing the risk of infection still further.”

The company was deep cleaning the site using a disinfectant called BioMist. It had been used three times in the past week. He said: “We also began BioMisting our vehicles on this week, to further protect our drivers while they work.”

It was revealed 83 people were self-isolating at the time the letter was written earlier this week. That was at odds with the estimate given by Unite union representative John McGookin on BBC Radio Wiltshire on Monday, when he said half of the depot’s 750-strong workforce was absent.