What Is Cyclospora- and Should Canadians Be Worried About the Outbreak?

A dietitian’s guide to what’s happening, which symptoms to watch for and whether you need to stop eating salad

You may have recently seen unsettling headlines about a parasite called Cyclospora causing thousands of gastrointestinal illnesses across the United States.

Because fresh produce—particularly lettuce—has been implicated, it is understandable that Canadians are asking:

Is our food affected too? Should we avoid lettuce? And how worried do we actually need to be?

Here is what we know as of July 17, 2026.

What is Cyclospora?

Cyclospora cayetanensis is a microscopic parasite that infects the small intestine. The illness it causes is called cyclosporiasis.

People become infected by consuming food or water contaminated with the parasite, typically through microscopic amounts of human fecal matter.

Yes, it sounds awful—but it is important to understand how transmission works.

Cyclospora is not usually spread directly from one person to another. After it leaves the body, the parasite needs time in the environment to become infectious. This means you are more likely to become sick from a shared contaminated food or water source than from being around someone who has the infection.

Cyclospora has frequently been associated with fresh produce because many fruits, vegetables and herbs are eaten raw. Previous outbreaks have involved foods such as:

Leafy greens
Fresh herbs
Berries
Snow peas
Other raw fruits and vegetables

The produce itself does not naturally “contain parasites.” Contamination may occur when food comes into contact with contaminated water, soil, equipment or hands during growing, harvesting, processing or distribution.

What is happening in the United States?

The U.S. is currently experiencing a substantial seasonal increase in cyclosporiasis.

As of July 13, 2026, the U.S. Centers for Disease Control and Prevention had received reports of:

1,645 laboratory-confirmed domestically acquired cases
Cases across 34 states
141 hospitalizations
No reported deaths

The CDC was also aware of more than 5,100 additional cases requiring further analysis. Officials expect case numbers to continue rising partly because there can be several weeks between someone becoming sick and their case being confirmed and reported.

Those numbers represent several investigations and do not necessarily mean that every case came from one food.

However, investigators have identified one significant outbreak linked to shredded iceberg lettuce served at certain Taco Bell restaurants in:

Indiana
Kentucky
Michigan
Ohio
West Virginia

The FDA’s traceback investigation connected the lettuce served at affected restaurants to a single supplier sourcing iceberg lettuce from Mexico. Taco Bell has committed to stopping use of lettuce from that supplier.

As of July 16, this particular five-state outbreak included 1,644 illnesses and 94 hospitalizations, with no deaths reported. Not every Taco Bell location in those states received the implicated lettuce, and the investigation remains ongoing.

The current FDA warning is specifically directed at shredded iceberg lettuce from Mexico served at implicated Taco Bell locations in those five states. It is not currently a recommendation for everyone in North America to stop eating all lettuce or all fresh produce.

Why do Cyclospora outbreaks happen during the summer?

Cyclospora infections tend to rise during the spring and summer. The CDC considers May through August the typical cyclosporiasis season in the United States.

Canada also commonly sees a seasonal increase in cases during warmer months.

This may reflect a combination of factors, including:

Greater availability and consumption of imported fresh produce
Seasonal growing and harvesting conditions
Travel to regions where Cyclospora is more common
The complex distribution systems used for fresh produce
Delays in identifying a shared food exposure

Tracking the source can be challenging because symptoms often begin about a week after exposure. By the time someone becomes sick, they may have eaten several meals and may not remember every ingredient they consumed.

What symptoms should you watch for?

The most common symptom is frequent, watery diarrhea.

Other possible symptoms include:

Abdominal cramping or pain
Bloating
Increased gas
Nausea
Loss of appetite
Unintentional weight loss
Fatigue
Headache
Body aches
Low-grade fever
Occasional vomiting

Symptoms usually begin around one week after exposure, although they may appear anywhere from approximately two to 14 days later.

One of the more characteristic features of cyclosporiasis is that symptoms can appear to improve and then return.

Without treatment, symptoms may last for several weeks or longer. Some people have cycles of diarrhea and improvement rather than one short, straightforward stomach illness.

Not everyone who becomes infected develops symptoms.

When should you contact a healthcare provider?

Many brief episodes of diarrhea are caused by viruses, medications, dietary changes or other relatively minor issues. Cyclospora becomes more important to consider when diarrhea is:

Particularly watery or frequent
Lasting more than several days
Improving and then repeatedly returning
Associated with significant fatigue or weight loss
Occurring after travel
Occurring after eating food connected to a known outbreak
Causing signs of dehydration

Seek medical attention sooner if you cannot keep fluids down, feel faint or confused, have very little urine, notice blood in your stool, develop severe abdominal pain or have other concerning symptoms.

Older adults, young children and people who are pregnant or immunocompromised may need earlier assessment because prolonged diarrhea and dehydration may affect them more significantly.

Cyclospora is diagnosed through stool testing. It can sometimes be missed by routine parasite testing, so a healthcare provider may need to specifically request testing for Cyclospora.

Confirmed infections can be treated with prescription antibiotics. Hydration is also important, particularly when diarrhea is frequent.

Are Canadian cases connected to the U.S. outbreak?

At the time of writing, the Public Health Agency of Canada is not investigating a Canadian cyclosporiasis outbreak connected to the large U.S. outbreak.

Canadian cases are being reported, but health authorities have not identified a broad Canadian link to the affected U.S. restaurants or lettuce supply.

For example:

Quebec reported 107 cases as of July 11, although most appeared to be associated with travel, primarily to Mexico.
British Columbia reported 93 cases, with officials describing current levels as typical and noting that many cases are travel-related.
Alberta reported six cases, with most recent cases connected to travel to Mexico and none linked to U.S. travel.
Ontario had reported two cases to Public Health Ontario earlier in the year.

Canadian officials routinely see some travel-related and domestically acquired Cyclospora cases. The Public Health Agency of Canada has noted that Canada often experiences a spring and summer increase associated with imported fresh fruits and vegetables.

The Canadian Food Inspection Agency has also indicated that it is not currently considering restrictions on fresh produce imports from the United States.

So, while the situation deserves monitoring, there is currently no reason for Canadians to assume that all U.S. produce—or all imported produce—is unsafe.

Should Canadians stop eating lettuce or salad?

Based on the current information, probably not.

Fresh fruits and vegetables remain important sources of fibre, vitamins, minerals and protective plant compounds. Avoiding all produce because of one investigation would create a much larger nutritional downside without meaningfully eliminating every food-safety risk.

A more proportionate response is to:

Follow Canadian recall and public-health notices
Avoid any specific food identified in an official advisory
Wash fresh produce under cool running water
Keep produce refrigerated
Separate produce from raw meat, poultry and seafood
Wash your hands before preparing food
Clean cutting boards, knives, containers and countertops
Discard spoiled or damaged produce

For firm produce, gently rubbing or scrubbing the surface under running water may help remove dirt and some contaminants.

Do not wash produce with soap, bleach or household disinfectants.

It is also important to know that washing produce does not guarantee the removal of Cyclospora. The parasite can be difficult to wash completely from delicate, uneven surfaces such as lettuce leaves and berries.

That does not make washing pointless. Washing is still a recommended food-safety practice—it simply cannot turn a recalled or implicated food into a safe one.

If public-health officials recall a product or tell consumers not to eat it, throw it away or return it. Do not try to rescue it by washing it more thoroughly.

Cooking

The good news is that heat kills Cyclospora.

Cooking foods to normal cooking temperatures is expected to destroy the parasite, which is one reason outbreaks are much more commonly linked to foods that are eaten raw.

For example:

Spinach added to soup or sautéed
Snow peas stir-fried
Herbs cooked into sauces, soups or curries
Vegetables roasted or steamed

These are much lower-risk than eating those same foods raw if they happened to be contaminated.

However, cooking isn’t always practical. No one wants cooked lettuce on a Caesar salad or wilted berries on their fruit platter. Since many of the foods associated with Cyclospora are typically eaten fresh, prevention relies much more on safe agricultural practices, food processing standards, surveillance and recalls than on what consumers can do at home.

What if you recently visited the affected U.S. states?

The current FDA recommendation applies to shredded iceberg lettuce from Mexico served at implicated Taco Bell locations in Indiana, Kentucky, Michigan, Ohio and West Virginia.

You do not need to do anything simply because you travelled through one of those states.

However, if you ate at a Taco Bell in one of the affected states and develop prolonged or relapsing watery diarrhea within roughly two weeks, contact a healthcare provider and mention:

Where you travelled
Where you ate
When your symptoms began
That you may have been exposed to Cyclospora

That information may help your provider select the appropriate testing.

Who should be extra cautious?

Most healthy adults recover from Cyclospora with appropriate treatment and hydration, but some people are at higher risk of complications from prolonged diarrhea and dehydration.

This includes:

Young children

Children become dehydrated more quickly than adults, particularly if they are experiencing frequent diarrhea or vomiting. Signs of dehydration include decreased urination, dry mouth, lethargy and, in infants, fewer wet diapers.

Older adults

As we age, our ability to compensate for fluid losses decreases. Older adults may become dehydrated more quickly, and diarrhea can worsen existing medical conditions or contribute to falls and confusion.

Pregnant individuals

Pregnancy does not appear to increase the risk of contracting Cyclospora or cause the parasite to infect the baby. However, severe diarrhea can lead to dehydration, which is important to avoid during pregnancy. Pregnant individuals with persistent diarrhea should contact their healthcare provider promptly.

People with weakened immune systems

Individuals with conditions or medications that suppress the immune system may experience more severe or prolonged illness. This includes people:

Receiving chemotherapy
Living with HIV/AIDS (particularly if untreated)
Taking medications after an organ transplant
Taking high-dose corticosteroids or other immunosuppressive medications for autoimmune conditions

These individuals may have symptoms that last longer or require closer medical follow-up.

People with chronic medical conditions

Those with kidney disease, heart failure or other conditions where maintaining fluid balance is important should seek medical advice sooner if diarrhea is persistent, as dehydration can have more significant consequences.

When shouldn’t you wait it out?

Remember- Seek medical attention promptly if you experience:

Signs of dehydration (dizziness, fainting, very dark urine or urinating much less than usual)
Bloody diarrhea
Severe abdominal pain
A fever that is high or persistent
Diarrhea lasting more than several days without improvement
Symptoms that improve and then repeatedly return
Persistent diarrhea if you are pregnant, immunocompromised, very young or an older adult

While many cases of diarrhea resolve on their own, Cyclospora often requires prescription antibiotics for complete resolution. Early assessment is especially important for higher-risk individuals.

The bottom line for Canadians

The U.S. Cyclospora outbreak is significant and investigations are ongoing. One large cluster has now been linked to shredded iceberg lettuce served at certain Taco Bell restaurants in five U.S. states.

However, there is currently:

No confirmed widespread Canadian outbreak connected to the U.S. event
No Canadian recommendation to avoid all lettuce or fresh produce
No Canadian restriction on American produce imports
No reason to panic or remove fruits and vegetables from your diet

Continue following routine food-safety practices, pay attention to official recall notices and seek medical care for prolonged or relapsing watery diarrhea—particularly after travel or a known food exposure.

The appropriate response here is awareness, not fear.

Dealing with digestive issues or are you someone who is at higher risk of illness and would like to discuss your nutrition needs with a dietitian? Book online for a 1:1 session here.

This article is for general education and does not replace individualized medical assessment. Outbreak information can change quickly; consult the Public Health Agency of Canada, Canadian Food Inspection Agency and your provincial public-health authority for the latest Canadian guidance.