Public health workers in Washtenaw County, Michigan, are trying to track down the source of a large Cyclospora outbreak after more than 900 people became ill with cyclosporiasis since mid-June. The investigation has turned into an intensive effort led in part by nurses who have been reassigned from other responsibilities to focus on the surge in cases.
Investigators are calling large numbers of sick residents and asking them to recall what they ate in the days before their symptoms began. Because that kind of memory work can be difficult, nurses are also using grocery receipts, restaurant records and food-tracking apps to help rebuild meal histories and look for overlapping items.
The work is slow and highly detailed. Health staff must compare hundreds of interviews, sort through shopping habits and identify patterns that could point to a common food exposure. One public health nurse in the county has reportedly spoken with more than 100 patients as officials continue piecing together the outbreak.
The response highlights how demanding foodborne illness investigations can be, especially when a large number of people are affected at once. In Washtenaw County, the priority remains understanding where the Cyclospora contamination may have come from while managing the strain the outbreak has placed on local public health staffing.
