Thing is i suspect this is normal accross the board in the manufacturing sector especially in food as most are not paid much so can't afford to take any time off if it's unpaid.
If you search the news it's full of stories like this and in some instances they have shut factories with high case numbers.
15 May
Three workers at a Cranswick meat processing factory near Barnsley die from coronavirus.
17 June
A major outbreak at the 2 Sisters food factory in Anglesey, North Wales
is revealed with 51 confirmed cases. The number of people infected rises to over 200 within a week.
The factory is closed on 18 June after the personal intervention of 2 Sisters founder Ranjit Singh, despite having carried on operating since 28 May when the outbreak was first uncovered by management.
Following the news, Welsh authorities scrap plans for local schools to re-open and consider imposing a lockdown on the island of Anglesey.
19 June
Almost 40 staff at Oscar Mayer-owned Rowan Foods
test positive for Covid-19. The Wrexham site has a total workforce of 1,500 and the number of confirmed cases rises to 97 five days later.
Tulip confims three cases at its Tipton plant, with a further 16 employees in self-isolation - taking the total cases at the West Midlands factory to 35 since March.
3 July
Young’s Seafood’s Annan plant in Dumfries & Galloway is identified as ‘high-risk’ following the identification of a Covid-19 cluster in the Scottish Borders. One plant employee is also confirmed to have contracted the virus, though Young’s stressed the worker had been on holiday since 19 June and contracted the virus “as a result of community contact with an external party”.
The staff member had made no contact with anybody from the site since going on holiday, Young’s added. Precautionary testing over the coming days of 134 employees at the site returned negative results.
3 July
2 Sisters Food Group confirms it has
reopened its Llangefni site, a fortnight after production was temporarily halted. By 12 July, Public Health Wales had confirmed a total of 221 cases at the plant, alongside 138 at Kepak’s Merthyr factory and 305 at Rowan Foods in Wrexham.
3 July
Walkers confirms at least 28 staff have tested positive for coronavirus at its Leicester plant.
12 July
Some 73 cases are confirmed at Herefordshire-based veg grower
AS Green & Co, with a total of 200 workers self-isolating. The outbreak is the first to be recorded at a farm in the UK.
13 August
292 employees test positive at Greencore, which makes food to go products for M&S, Moulton Park Industrial Estate site in Northampton.
17 August
2 Sisters Food Group
temporarily closes its Coupar Angus processing plant in Tayside after four Covid Cases were cofirmed among its workforce. Fyffes also
closes its Coventry banana ripening plant for two days after 30 cases were confirmed.
18 August
More than 70 workers at Bakkavor’s Newark factory receive positive results for Covid-19 after all 1,600 staff members at the plant are tested.
20 August
Cranswick announces the temporary closure of its Ballymena plant due to an increase in local transmission across Northern Ireland and “a number of confirmed cases” at the plant, which employs 500 staff.
21 August
Greencore announces
the temporary closure of its Northampoton plant following the positive tests it confirmed earlier in the week. 2 Sisters also confirms the number of positive cases at Coupar Angus has risen to 110.
22 August
An outbreak is confirmed at
Banham Poultry’s plant in Attleborough, Norfolk, with seven positive cases prompting a wave of testing by local health officials.
2 September
Millers of Speyside became the latest meat supplier to temporarily halt production, after confirming seven cases at its factory in the Scottish Highlands.