Cyclospora outbreak in the US: More than 4,000 confirmed infections

The trigger is a parasite called Cyclospora. It infects the small intestine and causes watery diarrhea with frequent, sometimes severe bowel movements. Many of those affected cannot remember exactly, because the symptoms only appear after about a week or later.

Cyclosporiasis outbreaks typically occur in summer. The current outbreak is significantly larger than previous ones. The US Food and Drug Administration (FDA) continues to suspect chopped iceberg lettuce from a supplier in Mexico as the source of the parasite, although test results have not yet confirmed this.

FDA suspects iceberg lettuce from Mexico

Over the weekend, the FDA had announced that a sample from the company Taylor Farms in Mexico had tested "falsely positive" for the Cyclospora parasite. Nevertheless, traceback investigations by the FDA continued to point to chopped iceberg lettuce from the company as the cause of the outbreak, the agency wrote on Monday on the platform X. The FDA said it would continue the investigation and ensure that affected products are removed from the market.

Taylor Farms said the agency had subsequently apologized. The cause behind the illnesses remains unclear.

Transmission mostly through contaminated food

According to the CDC, the parasite is typically not transmitted from person to person, but through food or water contaminated with feces. Since this often goes unrecognized or unreported, the actual number of cases is likely to be significantly higher, according to the agency.

The parasite is not directly contagious as soon as it is excreted. It must first mature, which takes days to weeks. This is why it is unlikely that people will infect each other.

It is conceivable that food was irrigated or washed with water contaminated by untreated wastewater. Or flooding could have flushed wastewater contaminated with human feces onto agricultural fields. Because contaminated food or contaminated drinking water is usually the trigger.

Criticism of health authority's resources

Precisely because so many individuals and states are affected, there are probably several sources of infection. This occurs through human feces, since the Cyclospora parasite infects only humans.

It usually heals on its own. A Cyclosporiasis infection is really only dangerous if an infected person becomes severely dehydrated from the diarrhea. People with a weakened immune system or older people are particularly at risk. It can be treated with an antibiotic containing the active ingredients trimethoprim-sulfamethoxazole. Without treatment, an infection can last several weeks.

Critics doubt that the US health authority is sufficiently equipped after the cuts. Hospital treatment is only necessary in a few cases; in many cases, diarrhea is not investigated.