Two more children are thought to have the E.coli O157 infection following a suspected outbreak in Fife.
Investigations into the outbreak are continuing
Paediatric staff are checking the youngsters to establish whether they require hospital treatment.
Five toddlers remain in hospital with kidney failure and 18 other possible cases have now been identified.
NHS Fife said that these were all linked to the Careshare nursery in Dunfermline. Investigations into the source of the outbreak are continuing.
Experts have speculated that the infection many have been brought into the nursery through an adult or a child and then been passed from person to person.
Dr Charles Saunders, consultant in public health medicine for NHS Fife, said an incident control team would meet again on Sunday to continue its investigation into the possible cause of the outbreak.
He said the five children being cared for at the Royal Hospital for Sick Children in Glasgow were confirmed as having kidney failure.
"Two additional children have been identified as having E.coli O157 infection," he said.
"These children are being checked by paediatric staff today to see if any hospital treatment is needed.
"A total of 18 people are regarded as being possible cases, all of which are linked to Careshare nursery. These people are all at home and are being followed up and investigated."
Twenty calls were made on Friday to a telephone helpline which is open from 0800 to 2200 BST each day on 08000 28 28 36.