(CBS News) NEW YORK -- The mystery over the cyclospora outbreak has. Cyclospora is a dangerous parasite that causes stomach illness. The Centers for Disease Control and Prevention said Thursday there are now 397 cases in 16 states, but no one has yet identified the source.
In early July, days after eating salads at home and at restaurants in Texas, Suzie Matteis developed diarrhea that persisted for weeks before a test found cyclospora.
"I had Montezuma's revenge, dysentery, something was going on," Matteis said. "Weight loss - I still don't have a normal appetite. I just want to get better because I'm used to being in good shape."
Matteis still doesn't know what food made her sick. Investigators in Texas have not named a source.
But this week, health investigators in Nebraska said the outbreak therethat came through "national distribution channels." Now, the CDC and the FDA are looking for the exact source of that contamination.
Iowa officials also said a prepackaged salad mix is to blame, but neither state is naming the company or companies involved. Both states cite laws prohibiting investigators from naming brands or companies if it's believed the contaminated product is no longer a public health threat. Officials believe the contaminated food is likely out of the food supply.
Matteis was given antibiotics and is slowly improving.
"I think that we should know where the food came from," she said. "I'm skittish. I don't know where to go to eat. I'm not out of the woods yet. I'm still feeling poorly."
We've been pushing the FDA and CDC for days on identifying the source. The CDC told us that just because a certain brand of salad is infected, it doesn't mean that brand is the ultimate source of the infection. For example, it could come from a common distributor or a common processing plant which involves a lot of other brands.
For now they're saying they're getting closer, they're eliminating certain things and they're probably going to give us more information soon. Right now, they're not ready to say anything more.