A little girl of eight has died after contracting E. coli 0157.
The child - who is thought to be from Dalrymple in East Ayrshire - passed away at the Royal Hospital for Sick Children in Glasgow.
A spokesperson for NHS Ayrshire and Arran said they did not think the case signified an outbreak, and have not identified a source for the infection which could indicate a risk for other people.
Dr Jane Cooper, a consultant in public health medicine, told the BBC:
"Sometimes it is possible to identify a particular source of E. coli O157 infection. An outbreak may occur if a number of people are exposed to the same source. NHS Ayrshire and Arran is satisfied that this case is not part of an outbreak, and has not identified a particular source which might represent a risk to others.
"E. coli O157 infection is very easily picked up and sometimes investigations cannot identify either a particular source, or any way in which the risk of infection could have been avoided."
Symptoms of E. coli usually come on after a person has consumed contaminated foods or drink, or has been in contact with animals infected with the bacteria.
The health board advices that members of the public can reduce their risk of infection by washing hands after contact with possible sources such as raw food and milk and animal faeces.