A parasitic infection, caused by Cyclospora and stemming from contaminated salad greens, has cause more than 500 people in the United States to become ill. The U.S. Centers for Disease Control and Prevention (CDC) has updated its numbers and marked 514 people in the country as being infected, with the numbers rising daily. The infection has affected 17 states, with one case reported in New York City.

Thirty patients have been hospitalized with severe symptoms, including cramps, abdominal pain, watery diarrhea, loss of appetite, bloating, nausea, fatigue, fever, and body aches. The single-celled parasite cannot be spread person to person. The incubation time for the parasite is around a week.

Cyclospora infection can be treated with trimethoprim-sulfamethoxazole, an antibiotic that is readily available.

The Food and Drug Administration (FDA) announced that it has tracked cases in Nebraska and Iowa to Taylor Farms de Mexico, a branch of Taylor Farms in Salinas, Calif. “It is not yet clear whether the cases reported from other states are all part of the same outbreak," the FDA said in its statement. "The investigation of increased cases of cyclosporiasis in other states continues."

Texas has the highest number of cases at 206, and most of the people who have become ill had eaten at Red Lobster and Olive Garden restaurants. Taylor Farms, however, does not supply either restaurants in Texas, so it is still a mystery as to the source of the state's contaminations.

The best way to protect your health from the infection is to wash all fruits, vegetables, and salad greens before consumption. Experts suggest even washing pre-packaged salads that have become increasingly popular in recent years.