India, July 25 -- The Centers for Disease Control and Prevention (CDC) has expanded its warning over the largest Cyclospora outbreak reported in the United States this year, saying the foodborne illness has now spread across nine states as investigators continue working to identify and contain its source.

Cyclospora is a microscopic parasite that spreads through contaminated food or water and causes cyclosporiasis, a gastrointestinal illness that can trigger severe diarrhea, stomach cramps, nausea, fatigue and loss of appetite.

While some patients have required hospitalization, no deaths linked to the outbreak have been reported this year.

In a Friday update, the CDC said the outbreak now spans nine states:

Federal health officials ha...