Michael White, the council’s director of education, announced this week, which ironically is national food safety week, that officials will be preparing new health guidelines for all its schools, backed by a staff development programme.

The guidelines will be made available to all authorities.

Twenty-two pupils in a primary 3 class were affected by the highly contagious and potentially fatal bug after eating goat’s milk cheese brought in by one of the pupils for a class project. Subsequent tests revealed the presence of the bacteria in goat faeces.

The class teacher also tested positive as did her teacher husband and a student teacher who was in the class at the time. Another six cases involved friends of the pupils.

Mr White said on Wednesday officials were confident the first wave of the outbreak had been contained and the priority now was to avoid secondary infections.

Two girls aged eight remained in hospital as we went to press, one receiving kidney dialysis treatment. A spokesman for Grampian University Hospitals Trust described their condition as “stable”.

Grampian Health Promotions will issue information packs for pupils about food hygiene and personal hygiene to all schools and educational establishments next week.

“We need to learn lessons from this outbreak and try to prevent this from happening again,” Mr White said. “We intend to set up guidelines covering major issues and we also intend to improve staff awareness.”

The new guidelines for staff will cover the major communicable diseases of hepatitis, meningitis, E coli and dysentery. They will also advise schools on a range of health and hygiene issues, including handling food in class projects, farm visits and storing packed lunches.

The staff development programme, which will be run with the help of Grampian Health Board officials, aims to ensure that at least one member of staff has sufficient knowledge about these diseases in each of Aberdeenshire’s 16 educational “clusters” (which include schools, community education centres and leisure centres). “Schools do need extra help,” Mr White said.

Health and education officials decided to close the primary three classroom at Macduff after the outbreak was diagnosed, but defended their decision not to close the school.

In a letter to parents, Dr John Curnow, consultant in public health medicine with Grampian Health Board, said shutting the school “is likely to do more harm than good”. While the pupils were together at the school, they were benefiting from good hygiene messages which teachers were reinforcing.

Dr Curnow appealed to parents to ensure children washed their hands after going to the toilet and before eating food.

Pupils who were tested positive will require two consecutive negative samples before being allowed back to school. Others without symptoms (diarrhoea, vomiting, stomach cramps) will be able to return next Monday if they continue to be free of the bacteria.