Vegetable pickers at a farm where 73 people tested positive for Covid-19 said they had hygiene concerns about the site.
Two workers said they had to share one toilet with up to 60 others at A S Green and Co in Herefordshire, which went into lockdown after the tests.
The couple are self-isolating at home in addition to 200 or so workers said to be in quarantine at the site's live-in accommodation.
The farm has been asked for comment.
Later, West Mercia Police said that three farm workers, including one who had tested positive for Covid-19, had left the site.
Dr Helen Carter, from Public Health England, said: "We aware aware that three individuals have left the farm against our guidance and advice and we are working with the West Mercia Police force to make sure they are safe and well."
Asked if they had been traced, Dr Carter said "at the moment, police are trying to find their location".
Responding to concerns about workers' well-being, a spokesperson for public health in the county said the owners of the farm, which supplies national supermarket chains, were doing "their very best in this difficult situation".
Brandon Burridge and Leah Johnson, a couple from Malvern, Worcestershire, signed up to work on the farm after seeing its Pick for Britain adverts in the local press.
Their last day of work was 2 July and they said the first they heard of the outbreak was in the media.
They said no-one from the farm had been in touch over the outbreak, and claimed they had been blocked from a company WhatsApp group after asking questions.
They said they were now self-isolating in their homes and awaiting the result of their own tests, which they say they organised themselves.
Image caption Workers are self-isolating at this farm in HerefordshireMs Johnson, 21, said during an induction process about 15 people had been sitting on shared benches with no mention of keeping 2m (6ft) apart.
"There was nothing about hand sanitiser, we weren't given any. We were not allowed to wear gloves," she said.
"It seemed strange to us, but we thought because it was an outdoor job, the risk of coronavirus would be low.
"But we hadn't considered the shared facilities.
"People were saying 'there is only one toilet' - that is ridiculous - and it got quite gross quite quickly, and we were told [by other team members] to avoid it all costs.
"There was one bit of hand sanitiser in the toilet."
Mr Burridge, 22, said: "I tried to ring them to ask why we hadn't been informed [of the outbreak] as I thought it was their duty to say so.
"But we were told that our usual contacts weren't available. The woman on the phone offered to pass on the message, but we didn't get a response. So I emailed them but I still haven't had a response.
"And we've been blocked from the team Whatsapp group."
Workers at the farm, which employs a mix of seasonal workers from the UK and abroad, are being supported by public health staff, who are providing food and other provisions, along with translators.
On BBC Breakfast on Monday, Karen Wright, director of public health for Herefordshire, said the priority was the wellbeing of people on the site and containing the outbreak, adding the risk of transmission of Covid-19 from food was low, and there were no "particular concerns about any individual's health".
She said of workers: "I think it's fair to say that anybody in this situation would be concerned, but generally they are feeling supported."
Adding the farm was home for those who lived on site, she said it was important they remained there while looking after their health, and that local workers were also self-isolating as a precaution.
Nobody was working on the farm currently, she said, "because people are either positive or they are identified as a contact because we are treating everybody on the farm as being a contact".
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