The U.S. Food and Drug Administration is conducting an investigation on the recent cyclosporiasis outbreak linked to cilantro infected with human feces.

A total of 384 people from 26 states have suffered from cyclosporiasis, with clusters of the illness observed in Texas, Georgia and Wisconsin. Of these, 226 or 59 percent were experienced since May 1. None of those who got sick travelled outside the U.S., according to the FDA.

Traceback investigations conducted by the FDA and health officials from Texas and Wisconsin found that people who got sick ate in restaurants that got their cilantro from certain farms in Puebla, Mexico.

Cilantro is the primary suspect vehicle for the cyclosporiasis outbreak based on investigations on the cluster illnesses in Wisconsin and Texas. Further investigations are being conducted in order to identify the specific food product consumed by those who got sick, according to the Centers for Disease Control and Prevention.

Last month, the FDA announced a partial ban on cilantro coming from Puebla, Mexico after federal health officials found human feces in certain cilantro farms during an on-site inspection. The partial ban will be imposed from April 1 to August 31 every year until further notice.

Cilantro shipments from other parts of Mexico will be allowed to enter the U.S. as long as they are accompanied with proper documentation proving they are not from Puebla. The FDA is also preparing a "green list" of fresh cilantro suppliers from Puebla that will not be banned.

The CDC describes cyclosporiasis as an intestinal illness characterized by watery diarrhea, bloating, loss of appetite, fatigue, weight loss, nausea, cramping and increased gas. It is caused by a parasite called Cyclospora, which is ingested through food or water contaminated with feces.

Cyclospora most commonly exists in tropical and subtropical areas. In the U.S., cyclosporiasis outbreaks are often linked with imports of fresh produce. The CDC recommends proper handling of fresh produce to consumers.