Two nurseries in the same small town have been closed due to an outbreak of e.Coli which saw several children hospitalised.
Church Road Pear Tree Nursery in Haddington, East Lothian, has been shut while health authorities carry out an investigation.
In total 28 cases have been identified - with most said to be mild.
However, some are in hospital in a stable condition.
Another nursery in Haddington, Meadowpark Pear Tree, has also been closed as a precaution after people connected with it reported symptoms.
NHS Lothian says a specific source has not yet been identified but advanced microbiological testing is under way to identify the strain of the infection and any links.
So far, cases have been confined to the nursery, households of the children and close contacts.
"We know that this will be an anxious time for many of those who are directly affected by the infection," Dr Richard Othieno, chairman of the incident management team, said.
"We have written to parents and carers of the children affected and to staff at the nursery to provide the most up to date information and ongoing health advice.
"NHS Lothian has a robust surveillance system in place to identify E. coli cases which helped us to identify these cases early and put in place essential control measures to prevent further spread.
"This outbreak reinforces the importance of washing hands regularly, particularly before eating or preparing food, and after going to the toilet."
Less than one mile separates the two nurseries in Haddington which, on the bank of the River Tyne, developed as a milling settlement.
The health authorities continue to work with both nurseries.
Dr Othieno added: "We continue to provide support to the nursery and those parents and carers who have been directly affected.
"We have encouraged parents to keep their children away from other children and those at higher risk until their negative results have been received."
