In a follow-up to a report two weeks ago, Public Health Wales has declared the outbreak of E. coli O157 that affected three children in the Conwy area over.
A total of 83 other people were screened for the infection as part of the Public Health Wales and Conwy County Borough Council investigation.
Everyone screened has received a negative result and no further cases of infection were identified.
A childcare provider closed voluntarily as a result of the outbreak but has since reopened. All staff and children received negative test results before returning.
The affected children have other links to one another, and the childcare setting is not believed to be the source of the infection or where transmission between the children took place.
All three children are recovering well at home.
Dr Chris Whiteside, Consultant in Communicable Disease Control, said: “We are satisfied that as a result of the infection control procedures put into place when this outbreak came to light, further spread of infection was prevented.
“Everyone who could have been put at risk has been screened and has tested negative and we are able to declare this outbreak over.
“E. coli O157 is a very serious infection that causes very severe diarrhoea, sometimes with blood in it, abdominal cramps and fever. In children, it can cause kidney failure that can prove fatal.
“It is not uncommon for outbreaks of E. coli O157 to be associated with children having contact with farm animals. The infection can also be contracted by eating contaminated food or drinking unpasteurised milk.”