Seven members of staff have now tested positive for coronavirus at a McDonald's branch in Bolton.
The restaurant had already been closed for a deep clean when two workers contracted the virus last week.
Now a further five members of staff at the China Gardens branch near Bolton town centre have been found to have Covid-19, a spokesperson for the fast food giant said.
None of those members of staff have returned to the building - and they are all self-isolating.
The restaurant has reopened, but is only operating as a takeaway and delivery service, following yesterday's announcement on new lockdown rules in Bolton.
A spokesperson for McDonald's said: “In total we have had seven employees test positive for COVID-19 at the China Garden restaurant.
ll these people are self-isolating and have not returned to the restaurant since it was deep cleaned by an external cleaning company.
"We continue to work closely with Public Health England and the Environmental Health Officer, following their guidance to ensure we are operating safely.”
McDonald's says each employee is given a temperature check before the beginning of their shifts and has to wear a face covering, use hand sanitiser and maintain a 2m distance whenever possible.
Bolton has the highest rate of coronavirus infection in the country, with figures from Public Health England showing more than 120 new cases per 100,000 people in the last week.
Residents have been asked to avoid any travel on public transport if possible and refrain from socialising with members of another household - even outdoors.
