"Illiterate carers who sleep during their shifts" are being used to make up for a worrying shortage of nurses at a public retirement home, the nurses' union said.

The carers, most of whom are foreign and do not speak Maltese, are employed by Health Mark, a subsidiary of Silvio Debono's DB Group.

MUMN President Colin Galea this morning led a protest of nurses outside the St Vincent de Paul residence, calling for an urgent meeting with Parliamentary Secretary Justyne Caruana, and insisting he would not rule out industrial action in the coming days.

A study commissioned by the union and residence management last year, he said, had called for a doubling of the nursing staff working at the home.

Mr Galea said this had been ignored by the government, which was instead turning to the private sector career provider to fill in the gaps.

"This raises serious concerns over the quality of care being given to residents here, many of whom have high levels of dependency," he said.

Carers had turned the provision of care into a factory operation, he said, adding that after brief rounds many would retire to a room given to them in the residence and sleep on "mattresses on the floor".

There are currently some 300 nurses charged with caring for more than 1,000 residents at the Marsa home. Large wards of more 40 residents were being cared for by just two nurses during the day, and often one nurse at night. This, he said, was unacceptable.

To make matters worse, he said, problematic wards, such as that dealing with dementia patients, were often being left without nurse supervision, or not enough to help deal with the patients' requirement.

"Nurses are only human. Can you imagine the stress of having to look after a ward without the necessary support," he said.

The situation was further compounded by a lack of approved leave, including on weekends. Study leave was even difficult to get ahold of, he said.

Mr Galea said he expected to hear back from Dr Caruana in the coming days.