Since May, several cases of the intestinal disease cyclosporiasis have been reported in the United States.
According to the U.S. Centers for Disease Control and Prevention (CDC), cases have been identified in 31 states, NPR reports.
A total of 843 cases have been recorded, but the CDC believes the actual number may be higher.
Many people recover without seeking medical care, and it can take several weeks for all cases to be officially reported.
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The disease has been identified in people ranging in age from 5 to 88.
Authorities search for the source
The CDC is still investigating the source of the outbreak. As part of the investigation, officials are interviewing people who became ill about what they ate.
However, identifying a common source can be difficult because symptoms may not appear until several days or even weeks after infection.
According to the U.S. Food and Drug Administration (FDA), previous outbreaks have been linked to foods including raspberries, cilantro, basil, snow peas, and lettuce.
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Advice for consumers
The CDC recommends thoroughly washing fruits, vegetables, and fresh herbs, as well as washing hands before and after preparing food.
Heating food to at least 70°C (158°F) can also kill the parasite.
According to the CDC, efforts are continuing to identify the food or beverage that may be responsible for the outbreak.
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