The number of E.coli cases in the south Wales outbreak has risen again to 122, although health officials said they believed it has now reached its peak.
The total rose by two on Monday and another five on Tuesday. But that compared with 40 new cases at the weekend.
Two cases also emerged in the Vale of Glamorgan and Gwynedd but these were not immediately linked to the outbreak.
Meanwhile, assembly members will debate the issue on Wednesday.
Health officials said there were no new schools where exposure to the source of E.coli resulted in infection.
As the latest figures were released on Tuesday, the outbreak control team said in a statement: "It is now clear that case numbers are in decline".
Officials produced statistics showing that most people fell ill before control measures were introduced.
Since the first cases emerged on 18 September, the outbreak has been confined largely to the south Wales valleys.
The first case also emerged in the Vale of Glamorgan, in a boy aged 12 from Stanwell Comprehensive, Penarth.
Another case was also reported in the Meirionnydd area of Gwynedd.
There is no confirmation, however, whether these latest cases are linked to the outbreak. Gwynedd Council say it did not expect it to be connected, and officials were investigating the possible source of infection.
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