Explosive diarrhea illness spreads across US: New York, Texas, Illinois among hardest-hit states as CDC investigates parasite cases. Check full list of affected places

A growing outbreak of a parasitic illness that can cause severe or “explosive” diarrhea has been reported across at least 17 US states, with health officials scrambling to identify the source of the infections. According to the US Centers for Disease Control and Prevention (CDC), 145 domestically acquired cases of cyclosporiasis have been reported so far, and 20 people have been hospitalized.

New York has reported the highest number of cases, while Texas, Illinois, Pennsylvania, New Jersey and Connecticut are also among the states seeing significant infections. The CDC says the real number of cases could be higher because many people recover without seeking medical care or testing.

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Which US states are reporting cases?

The CDC's latest surveillance data shows cases spread across 17 states. Reports indicate that New York is currently the most affected state, followed by Texas and Illinois, accoridng to USA Today. Cases have also been recorded in:

• Alaska
• Colorado
• Connecticut
• Florida
• Georgia
• Louisiana
• Massachusetts
• New Jersey
• New York
• North Carolina
• Ohio
• Pennsylvania
• Tennessee
• Texas
• Virginia
• Wisconsin

Health authorities are also monitoring a growing number of infections in Michigan.

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What is causing the outbreak?

The illness is caused by Cyclospora cayetanensis, a microscopic parasite that spreads through food or water contaminated with fecal matter. Investigators suspect contaminated fresh produce may be involved, but no specific food item has been identified yet. Cyclosporiasis is a parasitic infection that causes unpleasant gastrointestinal symptoms often associated with food poisoning, such as diarrhea, nausea and vomiting.

The CDC, FDA and state health departments are currently investigating multiple clusters of cases to determine whether they are linked to a common source. However, officials say there is currently no evidence that all reported infections stem from a single nationwide outbreak.

Symptoms to watch for

People infected with Cyclospora may develop symptoms within two to 14 days after consuming contaminated food or water. Common symptoms include:

• Watery or explosive diarrhea
• Stomach cramps
• Nausea
• Loss of appetite
• Bloating and gas
• Fatigue
• Weight loss

Without treatment, symptoms can last for several weeks and may even return after temporarily improving.

Why experts are concerned

Although no deaths have been reported, at least 20 patients have required hospitalization. The outbreak is unusual because most infected individuals had not recently traveled outside the United States, suggesting the source of contamination is domestic.

Public health experts say Cyclospora infections typically increase during spring and summer months, with outbreaks often linked to fresh produce such as cilantro, basil, lettuce and berries in previous years.

How to reduce your risk

While investigators work to identify the source, health officials recommend:

• Washing fruits and vegetables thoroughly before eating
• Scrubbing firm produce such as melons and cucumbers
• Practicing good hand hygiene
• Seeking medical attention if severe diarrhea persists

The CDC says the investigation remains ongoing and additional cases may be reported as surveillance continues.

FAQs

What illness is spreading across the US?
The illness is cyclosporiasis, an intestinal infection caused by the parasite Cyclospora cayetanensis.

Which states are most affected?
New York currently has the highest number of reported cases, followed by states including Texas and Illinois.

Can the illness spread from person to person?
No. Cyclospora infections are usually contracted through contaminated food or water rather than direct person-to-person contact.

Has the source been identified?
Not yet. Federal and state investigators are still trying to determine the source of the outbreak.

How many people have been hospitalized?
At least 20 people have been hospitalized, but no deaths have been reported so far.