State health officials say 160 people have been hospitalized as investigators probe produce and federal cuts slow the response.
On Friday, the Michigan Department of Health and Human Services reported 8,176 confirmed cyclosporiasis cases, a 6.6% increase from Thursday's 7,664 cases, with 160 people hospitalized.
The U.S. Food and Drug Administration linked the outbreak to shredded iceberg lettuce from Taylor Farms operations in central Mexico served at Taco Bell restaurants nationwide.
Local health agencies are struggling to investigate cases due to staffing shortages and federal funding cuts, with workers conducting labor-intensive interviews that can take up to 45 minutes each.
Staff at the Washtenaw County Health Department are investigating more than 770 cases, with spokesperson Susan Ringler Cerniglia saying, "We've got this huge volume and so many people working on it and it's not getting clearer."
MDHHS recommends cooking food to 158 degrees Fahrenheit to kill cyclospora; meanwhile, Wayne State University School of Medicine professor Teena Chopra said the epidemic curve seems to "plateau," though cases may continue rising through August.