Relatives of care home residents are demanding the government drops a requirement that anyone making visits out of the home must isolate in their room for two weeks afterwards.

Relatives will be able to take loved ones on trips outside but guidance published on Wednesday, to take effect from 12 April, states that even as vaccine coverage increases, visits out of homes risk reseeding Covid-19 infection, and so quarantine for 14 days will be required.

The Rights for Residents group has questioned whether the requirement is fair, and Julia Jones, a founder of John’s Campaign for better visiting rights, said it was illogical. “Care staff come in and out every day with no restriction on their community interactions,” she said.

Leigh Day, a law firm advising John’s Campaign, said it would “continue to press the Department of Health and Social Care to remove this element”. It appears likely to undermine the government’s decision to extend visits out to people aged over 65, after restrictions preventing them all together were dropped from the guidance issued in March.

John’s Campaign launched a legal challenge last week over the age limit, claiming that a blanket ban regardless of the health of the individual was discriminatory and unlawful.

The DHSC guidance acknowledges that the isolation rule “is likely to mean that many residents will not wish to make a visit out of the home”, which Jones described as “callous”. But the government said spending time with others outside the care home “will increase the risk of exposure to Covid-19 for the resident and potentially to other vulnerable residents on their return”.

It said: “Whereas it is possible to mitigate and manage infection risks within the controlled environment of the care home – including by testing anyone coming into the home – it is simply not possible to control the environment outside of the care home in the same way.”

At least one dose of vaccine has been given to 94% of residents of older adult care homes and 79% of staff, according to figures from NHS England published on Thursday.

One resident’s son, named as Michael in a statement released by Leigh Day, said he was “at my wits’ end with these outrageous deprivations of liberty”. He said his whole family has been vaccinated and every resident in his mother’s care home had had two vaccinations.

“I asked my mother what she wanted for Christmas and she said she didn’t want anything but to come to visit me and my family,” he said.

Two parents said their 30-year-old son who has autism and lives in a home could no longer make regular outings as part of his care plan. They said they were unable to visit him because of the distress it caused him when he did not understand why he could not leave with them.

The mother said her son “would never be able to do 14 days isolation. He says: ‘I am being good, Mum, but when am I coming home?’ We desperately miss him and feel as parents that all of our rights and [his] rights have been taken away. It’s like we don’t have any.”

A DHSC spokesperson said: “As part of the roadmap out of lockdown, we have updated guidance for care homes to support residents to enjoy out-of-care-home visits in the safest way possible, while also providing more opportunities for visits to take place in care homes. When the data shows it is safe, the government wants to go even further and allow more visits to take place.”