{"id":398484,"date":"2026-07-14T22:27:17","date_gmt":"2026-07-14T22:27:17","guid":{"rendered":"https:\/\/www.newsbeep.com\/us-ca\/398484\/"},"modified":"2026-07-14T22:27:17","modified_gmt":"2026-07-14T22:27:17","slug":"cyclosporiasis-and-the-bay-area-what-to-know-about-the-explosive-diarrhea-parasite-surging-in-the-us","status":"publish","type":"post","link":"https:\/\/www.newsbeep.com\/us-ca\/398484\/","title":{"rendered":"Cyclosporiasis and the Bay Area: What to Know About the \u2018Explosive Diarrhea\u2019 Parasite Surging in the US"},"content":{"rendered":"

Let\u2019s face it: Headlines about \u201cexplosive diarrhea\u201d are the headlines nobody wants to see.<\/p>\n

But amid the current national outbreak of cyclosporiasis \u2014 a foodborne stomach parasite that\u2019s infected thousands of people around the United States \u2014 it\u2019s hard to avoid the updates about the severe cramping, bloating and yes, the \u201cwatery diarrhea with frequent, sometimes explosive, bowel movements\u201d (in the Centers for Disease Control and Prevention\u2019s own words<\/a>) this disease causes.<\/p>\n

On Tuesday, the Centers for Disease Control and Prevention announced <\/a>that the agency had received reports of 1,645 confirmed domestic cases of cyclosporiasis \u2014 but was aware of over 5,000 more cases that required confirmation. So far, Michigan<\/a> has experienced the worst rises in cyclosporiasis cases, reporting over 3,000 cases as of Tuesday. Other states reporting surges of the disease include New York<\/a>, Illinois<\/a>, Ohio<\/a> and Texas<\/a>.\u00a0<\/p>\n

\"\"A doctor listens to a patient\u2019s heartbeat at the Mountain Valley Health Center in Bieber on July 24, 2019. <\/p>\n

Some good news: The California Department of Public Health says that California \u201cis not one of the states currently experiencing an increase in cases of cyclosporiasis,\u201d and that the state has actually seen fewer cases of cyclosporiasis this year than it did in 2025. As of Monday, the Centers for Disease Control and Prevention is only reporting <\/a>between one and 10 cases in the whole state, although the agency\u2019s map <\/a>of nationwide cases generally lags behind the figures being reported by the states themselves.<\/p>\n

But if you\u2019re in the Bay Area \u2014 or are planning to visit any of the affected states in the coming weeks \u2014 what should you know about your individual risk of cyclosporiasis? What\u2019s the source of this outbreak? Should you be thinking about your fruits and vegetables differently right now, and how can you reduce your family\u2019s chances of being hit by this truly unpleasant disease this summer?<\/p>\n

Keep reading for what we know about cyclosporiasis and California. (And be aware since we\u2019re talking about explosive diarrhea here, the details below are not really lunchtime reading.)<\/p>\n

Jump straight to:<\/p>\n

\nWhat is cyclosporiasis, and how do people get infected?\u00a0\n<\/p>\n

Cyclosporiasis \u2014\u00a0 pronounced \u201csigh-clo-spore-EYE-uh-sis<\/a>\u201d, similarly to \u201cpsoriasis\u201d \u2014 is a gastrointestinal disease caused by the cyclospora parasite.<\/p>\n

This parasite, which is too small <\/a>to be seen with the human eye, lives in the poop of people infected with cyclosporiasis. Other people can then become infected also by ingesting food or drink that\u2019s contaminated with those feces \u2014 for example, fresh fruits or vegetables that have been washed with contaminated water.<\/p>\n

\"\"The CDC recommends washing fruits and vegetables, among other steps.<\/p>\n

Cyclosporiasis isn\u2019t a new disease, and California \u201cexperiences cases of cyclosporiasis every year,\u201d according to a July 13 statement by CDPH.\u00a0<\/p>\n

\u201cIt\u2019s been around for a long time, but this year it\u2019s notable for the rate of increase, which is itself explosive,\u201d said Dr. Peter Chin-Hong, an infectious disease expert at UCSF.<\/p>\n

But \u2014 so far, at least \u2014 that\u2019s all in other states. CDPH said that from January to June 2026, California reported 41 provisional cases of cyclosporiasis, \u201ccompared to 80 cases during the same period in 2025.\u201d\u00a0<\/p>\n

\nIs cyclosporiasis in California right now?\n<\/p>\n

Because cyclosporiasis isn\u2019t a new disease, California \u201cexperiences cases of cyclosporiasis every year,\u201d according to a Monday statement by CDPH.\u00a0<\/p>\n

\u201cIt\u2019s been around for a long time, but this year it\u2019s notable for the rate of increase, which is itself explosive,\u201d said Dr. Peter Chin-Hong, an infectious disease expert at UCSF.<\/p>\n

\"FemaleA researcher works in a biochemist laboratory. <\/p>\n

But \u2014 so far, at least \u2014 that\u2019s all in other states. CDPH said that from January to June 2026, California reported 41 provisional cases of cyclosporiasis, \u201ccompared to 80 cases during the same period in 2025.\u201d The agency said that most of these 2026 California cases are associated with recent international travel.<\/p>\n

Since May 1, CDPH has reported four California cases of cyclospora in people who\u2019d been infected within the United States \u2014 two of whom had visited the Midwest.<\/p>\n

\nWhat are the symptoms of cyclosporiasis, and how fast do they start?\n<\/p>\n

Cyclosporiasis symptoms take a surprisingly long time to show up after you eat food contaminated with the cyclospora parasite: around one week, and up to two weeks.\u00a0<\/p>\n

This incubation time makes it even harder to trace the source of an outbreak, Chin-Hong said, since not only is it often difficult to remember exactly what you ate over a week ago, but by that time, contaminated produce may have cycled out of the store where you bought it.<\/p>\n

According to the California Department of Public Health, the symptoms of cyclosporiasis include:<\/p>\n

Watery diarrheaLoss of appetiteWeight lossBloatingStomach crampsIncreased gasNauseaFatigue<\/p>\n

This all happens because when it gets into your small intestines, the cyclospora parasite begins to reproduce. In addition to inflaming your insides, the parasite makes it far harder for the intestines to absorb any fluids or food \u2014 meaning it all passes straight through your system, resulting in that watery, often explosive diarrhea. (Vomiting with cyclosporiasis is far less common, Chin-Hong said.)<\/p>\n

One hopeful bit of information: Some people who get infected with cyclospora don\u2019t actually get any symptoms at all. But if you\u2019re still curious (and don\u2019t mind graphic descriptions of symptoms), you can browse this Reddit AMA <\/a>with someone who said they\u2019ve had cyclosporiasis for the last month.<\/p>\n

\nHow long can cyclosporiasis last, and is it treatable?\n<\/p>\n

What distinguishes the symptoms of cyclospora infection from, say, a gnarly bout of food poisoning?<\/p>\n

The answer is that cyclosporiasis is likely to cause what Chin-Hong calls a \u201cchronic diarrhea pattern, where you have diarrhea that might get better, and then it gets worse again and goes up and down\u201d \u2014 for several weeks or even longer.<\/p>\n

\"\"A registered nurse prepares a dose of the Moderna vaccine at St. Rose Hospital in Hayward, California, on Friday, Jan. 8, 2021.<\/p>\n

And whereas other conditions like norovirus will eventually go away on their own, you\u2019ll need treatment with antibiotics to resolve a cyclospora infection and make that diarrhea finally stop.\u00a0<\/p>\n

Anyone who suspects they have a cyclospora infection should reach out to their healthcare provider for a diagnosis, after which they can be prescribed a 7-10 day course of trimethoprim-sulfamethoxazole<\/a>. \u201cSome immune-compromised individuals may need a longer course,\u201d Chin-Hong said.<\/p>\n

\nWhat do we know about what\u2019s causing the current surge in cyclospora cases?\n<\/p>\n

The source <\/a>of the cyclosporiasis outbreak in the Midwest still isn\u2019t officially known \u2014 and according to NPR<\/a>, the CDC says it\u2019s still trying to identify where the parasites originated.<\/p>\n

At a Tuesday media briefing, CDC officials said that the agency believed that the cyclospora outbreaks in Michigan, Ohio, West Virginia and Kentucky were linked.<\/p>\n

Health officials in Michigan announced <\/a>Monday that lettuce or salad greens could potentially be the source of that state\u2019s outbreak, but that more evidence is needed. According to the Washington Post, state and federal officials are also investigating whether lettuce sold at certain Michigan locations of Taco Bell <\/a>may have played a role in the outbreak.<\/p>\n

\"\"Fresh raspberries for sale at a farmers market.<\/p>\n

In the past, people have been infected by consuming fruits or vegetables that were exposed to feces-contaminated irrigation water. Also, it\u2019s possible that food distributors may channel contaminated foods to both grocery stores and restaurants, making it hard to discern where tainted food came from.<\/p>\n

The CDC has faced criticism <\/a>in recent weeks for how federal cuts to state and local health department funding \u2014 totaling over $11 billion \u2014 may have impacted the agency\u2019s ability to track this outbreak.\u00a0<\/p>\n

\u201cThey\u2019ve cut down a lot on the surveillance systems that allow these things to be easily controlled,\u201d Chin-Hong said. \u201cAnd the longer it goes on, the harder it is to go and try to interview all these [patients] and to confirm the test with a lab test.\u201d<\/p>\n

In July 2025, President Donald Trump\u2019s second administration also reduced the scope of a federal program <\/a>which monitors for foodborne outbreaks like cyclosporiasis.\u00a0<\/p>\n

\nIf I\u2019m visiting an area with a cyclosporiasis outbreak, should I be avoiding certain foods to lower my risk?\n<\/p>\n

Cooking your produce to an internal temperature of at least 158 degrees will kill cyclospora.<\/p>\n

But cooking your fruits and vegetables this way might not always be realistic. And while washing produce isn\u2019t guaranteed to remove all traces of cyclospora<\/a>, when done thoroughly, it could help reduce your risk of infection.<\/p>\n

\"\"A cropped photo of a female hand carrying a shopping basket while choosing vegetables at a supermarket. Grocery shopping concept.<\/p>\n

Dr. Erika Noel, an assistant professor at Hawaii\u2019s medical school and a pediatrician on the island of Kauai, shared the following tips<\/a> for washing produce with the Associated Press:<\/p>\n

When washing items like cilantro and basil, separate the leaves.For green onions, cut off the roots, remove the outer layer and run them under water while rubbing the surface.Research shows that washing fruits and vegetables in vinegar can be helpful. Vinegar won\u2019t kill the parasite but can help remove it. Noel recommends submerging produce in a bowl filled with three parts water and one part vinegar and swishing it around for a few minutes. Using a salad spinner to rinse with water can help get rid of the vinegary taste.Instead of purchasing pre-mixed salad and washing individual leaves, opt for a head of lettuce and remove the outer layer.For melons, scrub the outside before cutting through, as the knife can carry germs from the rind into the fruit inside.Peel fruits and vegetables as much as possible.<\/p>\n

Don\u2019t forget to wash cutting boards and countertops. Alcohol-based hand sanitizers don\u2019t kill cyclospora, but soap and water are highly effective at killing or removing the parasite from hands.<\/p>\n

\nEven with low case counts in California, I\u2019m really worried about getting cyclosporiasis. What should I be doing?\n<\/p>\n

First of all, remember that according to CDPH, \u201cthere are no known local outbreaks in California, and no California cases are currently known to be linked to multistate outbreaks under investigation by the CDC.\u201d The CDC\u2019s surveillance map<\/a>, last updated on July 9, shows \u201c1-10\u201d cases currently reported in California.<\/p>\n

\u201cWe would have seen it if it was some distributor that we had, that the Midwest groceries or restaurants also use,\u201d Chin-Hong said. \u201cBecause it should all happen at the same time.\u201d\u00a0And because of the foodborne nature of cyclosporiasis, and the lack of human-to-human transmission, \u201cit\u2019s not like somebody from Michigan travels to California and then spreads it around,\u201d he said.<\/p>\n

\"\"Kenny McDowell holds a handful of onion microgreens at Three Sisters Garden in West Sacramento on Feb. 12, 2026.<\/p>\n

But all this might not stop you worrying about cyclosporiasis. Chin-Hong said that he\u2019s still eating fruits and vegetables \u201cwith wild abandon,\u201d albeit while washing his hands and his produce carefully \u2014 \u201cespecially green leafy vegetables under running water.\u201d\u00a0<\/p>\n

If you\u2019re anxious about inadvertently eating foods that might be linked to the current outbreaks in the Midwest, you might consider sourcing your produce from local farms to be more secure in where your food has come from, Chin-Hong said.<\/p>\n

Still worried? Chin-Hong said you could avoid higher-risk items that have traditionally been implicated in previous cyclosporiasis outbreaks, like leafy greens in bagged salad mixes, fresh herbs like cilantro and berries.<\/p>\n

Instead, he said you could opt for \u201clower-risk choices\u201d like bananas, oranges, avocados, melon and mangoes, because these options have rinds or skin that are removed before eating. When cutting into thick-skinned produce like melon, be sure to wash not just its outside but also your knife and your hands, to make sure you\u2019re not accidentally pushing any contamination from the skin into the flesh.\u00a0<\/p>\n

And as tough as the symptoms are, remember that effective antibiotic treatment for cyclosporiasis is available should the worst happen, he said.<\/p>\n

\nI\u2019ve got diarrhea, and now I\u2019m panicking. Could this be cyclosporiasis?\u00a0\n<\/p>\n

Right now in the Bay Area, getting diarrhea is way more likely to be due to another gastrointestinal disease.<\/p>\n

According to Stanford University\u2019s WastewaterSCAN, a team that measures viral levels in human sewage, both Norovirus and Rotavirus \u2014 gastrointestinal diseases which, like cyclosporiasis, cause prolonged diarrhea \u2014 have been detected in over 99% of samples from their sites across the Bay Area in the last three weeks.<\/p>\n

\"ShopperCustomers shop in the deli meat aisle of a grocery store in Miami in October. In 2024, Americans saw an increase in recalls of food and cosmetic products, with three main pathogens \u2014 salmonella, listeria and E. coli \u2014 posing the greatest overall risk of severe illness.<\/p>\n

While the seasonal waves of these viruses are coming to an end, both Norovirus and Rotavirus \u201care commonly detected in wastewater year-round,\u201d WastewaterSCAN\u2019s Amanda Bidwell said.<\/p>\n

Unlike these other diseases, you\u2019ll know it\u2019s cyclosporiasis if your diarrhea just won\u2019t go away, Chin-Hong said.<\/p>\n

\nCan humans transmit cyclosporiasis to each other?\n<\/p>\n

Not in the way you might be thinking. You\u2019re far, far more likely to get cyclosporiasis from ingesting food or fluid that\u2019s contaminated with the feces from an infected person you don\u2019t even know \u2014 for example, by eating fruit that was washed in water that contained feces \u2014 than by being near a person with cyclosporiasis.<\/p>\n

So far, 141 people have been hospitalized <\/a>nationwide with cyclosporiasis, according to the CDC\u2019s numbers from Tuesday \u2014 9% of confirmed cases.<\/p>\n

This story contains reporting from the Associated Press.<\/p>\n","protected":false},"excerpt":{"rendered":"Let\u2019s face it: Headlines about \u201cexplosive diarrhea\u201d are the headlines nobody wants to see. But amid the current…\n","protected":false},"author":2,"featured_media":398485,"comment_status":"","ping_status":"","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[6],"tags":[7,9,8],"class_list":["post-398484","post","type-post","status-publish","format-standard","has-post-thumbnail","category-california","tag-california","tag-california-headlines","tag-california-news"],"_links":{"self":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/398484","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/users\/2"}],"replies":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/comments?post=398484"}],"version-history":[{"count":0,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/posts\/398484\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media\/398485"}],"wp:attachment":[{"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/media?parent=398484"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/categories?post=398484"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.newsbeep.com\/us-ca\/wp-json\/wp\/v2\/tags?post=398484"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}