There are now new developments pointing to the source of the mysterious stomach bug that has sickened over 500 patients in 15 States across the United States, this is according to reports by the U.S. Centers for Disease Control and Prevention.

On its website, the agency announced that investigations traced the source of the parasite in two states -- Nebraska and Iowa -- to produce distributed by Taylor Farms de Mexico, the Mexican branch of Taylor Farms in Salinas, Calif.. The farm is the supplier of the contaminated pre-packaged salad mix to restaurants Olive Garden and Red Lobster.

In a report by HealthDay News, the U.S. Food and Drug Administration is still currently investigating if the same source can be blamed for the outbreak in other states. According to a statement released by the FDA, "It is not yet clear whether the cases reported from other states are all part of the same outbreak. The investigation of increased cases of cyclosporiasis in other states continues."

Though there have been no reports of fatalities yet, the number of people infected by the stomach bug still continues to rise even after reports reveal such a parasite is uncommon in countries like the United States. Symptoms of the cyclospora infection include diarrhea, stomach cramps, vomiting, nausea, and other common symptoms of stomach infection. If untreated it may last for weeks.

To respond to investigations possibly linking Taylor Farms to the outbreak in many other states, chairman and CEO Bruce Taylor explained in an email, quoted from HealthDay News:

"All our tests have been negative and we have no evidence of cyclospora in our product. We are working closely with the FDA to continue this investigation." He also added that they do not supply prepackaged salad mix in Texas, the state that now has the most number of infections.