Pubs and restaurants in a local lockdown area should check if customers come from a single household, according to the health minister.
The hospitality sector has been allowed to remain open in Caerphilly despite new rules which mean people living apart are unable to meet indoors.
Vaughan Gething said a big cause for a spike in Covid-19 cases was by people mixing in each other’s homes.
He also said residents booked on holidays could not travel.
Caerphilly county became the first area of Wales to go into a local lockdown at 18: 00 BST on Tuesday, with 151 people testing positive for coronavirus in the past week.
Positive people Coronavirus case rates
Cases per 100,000 people over the last seven days
Latest BBC analysis places Caerphilly as the second hardest-hit place in the UK – after Bolton – for Covid-19 case rates in the last week.
It said the case rate in the English town was 128 cases per 100,000 of the population, while Caerphilly had 80 per 100,000.
According to the latest data, published on Wednesday by Public Health Wales, the newest figure for Caerphilly is 83.4 cases per 100,000 people.
That covers the past seven days. Public Health England said it did not publish equivalent rolling figures.
As part of the lockdown in Caerphilly, people are unable to enter or leave the county without good reason as part of the lockdown measures which are expected to be in place until October at least.
“All pubs and restaurants need to look at their customers coming in and ask themselves, well [is that] really a group of people from a single household,” said Mr Gething.
“If people are taking bookings from a dozen people sitting at the same table, I think people really need to be asking themselves whether those are people following the rules.”
He said transmission of the virus has not been seen in pubs.
But Caerphilly council would be looking to make sure the new rules were followed, Mr Gething said, and he did not rule out closing the sector locally if necessary.
Positive people What do pubs say?
Glyn Davies runs the Smith Arms in Pengam, which he said had mostly an older clientele.
He said there was a “very mixed attitude” between customers, with the older ones not wanting to come to the bar so much because of the virus.
“Testing should have been brought in a lot earlier,” he said. “People were probably walking around with the virus without knowing.”
He felt that pubs were being made scapegoats but added: “Some pubs do flout the rules. We try and keep a distancing thing going in the pub but it’s very hard to police everything when you’re working.”
Asked whether pubs should make sure customers in groups were from the same household he said: “How can you do that? You can’t call people liars. You’d have to get people to bring birth certificates in.”
In Aberbargoed, former naval officer Mikaela Rees-Swindon became the landlord of The George in March – just a few weeks before lockdown.
The pub started serving outside again in July, then inside as restrictions eased.
“They aren’t making us shut – but they are making it impossible for us to run the place as a business,” she said.
“We are being told we have to check tables are being booked for single household groups – well that’s my Saturday cancelled.”
She said environmental health officials had made it clear the onus was on her and her staff to enforce social distancing and check track and trace information is correct.
“We’ve been doing everything right – it was going fabulously. But now they have crushed us overnight.”
Positive people What will the police do?
More than 60 vehicles were stopped in less than three hours of the first evening of the lockdown on Tuesday, though no enforcement action was taken.
However Gwent Police’s Chief Constable Pam Kelly said she did not want her officers to become “the Covid police” and said the force will not be using road blocks across the area.
“Our preferred option is to always work with communities,” she said.
“We will not be having road blocks where police officers are stopping people and stopping cars.
“But we will be out there engaging with our communities, and if people flout the law, there comes a time where we have to stop engaging and explaining – and if they are not prepared to adhere to the law, policing has to step in.”
Positive people Can I go on holiday?
During a wide-ranging Facebook live question and answer session on Tuesday evening, Mr Gething also said people in Caerphilly county could not go on holiday.
He said if residents had booked holidays they should speak to their providers, explain it would be a breach of the law for them to travel, and seek a refund.
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Officials would be in touch with package holiday providers and insurers to explain the “seriousness of the position and the risk to them and their business” if people from Caerphilly went on holiday,” he said.
Positive people Why is following the rules important to people?
After months of shielding, Yvonne Davies is feeling “pretty angry” at the situation in her home town of Caerphilly.
“You could actually see what was going to happen from day one,” she said.
“I only went to the precinct once and not a person had a mask on. They weren’t observing any social distancing and from then on it just got worse and worse.”
She said one supermarket had dropped distancing measures, with staff saying it was “back to normal”.
She feels people have become too relaxed about coronavirus: “They don’t realise how serious it is for a start.”
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