Category Archives: Protozoan

Ireland – Mayo’s Clare Island Hit with Cryptosporidium in Public Water Supply

Mayo’s Clare island has been hit with a “boil water” notice after the detection of cryptosporidium in the public water supply.

The “boil water” notice takes immediate effect, Uisce Éireann (Irish Water) and Mayo Council have said.

This follows consultation with the Health Service Executive (HSE) to protect the health of approximately 160 people on the island’s public water supply scheme.

The two bodies have said they are “working to implement solutions to lift the notice as quickly and as safely as possible in consultation with the HSE”.

Research – Project looks for cost-effective ways to monitor Cyclospora in agricultural water

Food Safety News

Research funded by the Center for Produce Safety is looking for a cost-effective method to detect Cyclospora in irrigation water, including a paper-based in-field water test.

The project seeks to use short strands of synthesized DNA, or aptamers, to bind to the target of interest — in this case, Cyclospora’s transmission stage.

Cyclospora cayetanensis is a protozoan parasite, that is nearly impossible to culture in the laboratory and requires complicated microscopy for detection in samples.

Lia Stanciu, Ph.D., with Purdue University, lead researcher on the project said,  “We were able to identify certain proteins on the cell membrane of Cyclospora that are unique only to Cyclospora and to which we can bind some DNA sequences.”

“We can synthesize those DNA-specific molecules. The next step would be to integrate those DNA molecules into something similar to a rapid COVID test or pregnancy test.”

Research – Studies Aim to Improve Detection, Control Methods for Cyclospora

Food Safety.Com

Two ongoing studies funded by the Center for Produce Safety (CPS) are looking to improve detection and control methods for Cyclospora cayetanensis. A complex protozoan parasite, C. cayetanensis is extremely challenging to culture in a laboratory setting, and requires complicated microscopy for detection in samples.

The first project, led by Purdue University’s Lia Stanciu, Ph.D., seeks to use “aptamers”—or short strands of synthesized DNA—to bind to C. cayetanensis. The aptamers would then be used to create a paper-based, low-cost, and easy-to-use water test for the parasite, similar to rapid COVID-19 or pregnancy tests.

The second study is exploring the use of zero-valent iron (ZVI) sand filters to remove C. cayetanensis from water, evaluating the basic principle that physical exclusion might be an option to reduce parasite burdens.

Research – Toxoplasma gondii in Foods: Prevalence, Control, and Safety


Toxoplasma gondii is an obligate intracellular parasite that causes toxoplasmosis, with approximately one third of the population around the world seropositive. The consumption of contaminated food is the main source of infection. These include meat products with T. gondii tissue cysts, and dairy products with tachyzoites. Recently, contamination has been detected in fresh products with oocysts and marine products. Despite the great health problems that are caused by T. gondii, currently there are no standardized methods for its detection in the food industry. In this review, we analyze the current detection methods, the prevalence of T. gondii in different food products, and the control measures. The main detection methods are bioassays, cell culture, molecular and microscopic techniques, and serological methods, but some of these do not have applicability in the food industry. As a result, emerging techniques are being developed that are aimed at the detection of multiple parasites simultaneously that would make their application more efficient in the industry. Since the prevalence of this parasite is high in many products (meat and milk, marine products, and vegetables), it is necessary to standardize detection methods, as well as implement control measures. View Full-Text

Canada – Mystery Cyclospora Outbreak spreads to Canada

Food Poison Journal

Public Heath Canada is working with its public health and food safety partners to identify possible ways non-travel related Cyclospora infections are occurring in Canada.

As of June 30, a total of 84 cases of Cyclospora infections were reported in the following provinces: British Columbia (1), Ontario (75), and Quebec (8). 4 individuals have been hospitalized and no deaths have been reported. To date, there is no recall or Public Health Notice, the investigation is ongoing.

In case you are experiencing Cyclosporiasis symptoms such as watery diarrhea (most common), cramping, bloating, increased gas, nausea, fatigue, and possibly vomiting and low-grade fever, it is important to report it. It can help to detect & resolve outbreaks early and prevent others from being harmed, and it enables better surveillance. If symptoms persist, seek medical care.

USA – Domestically Acquired Cases of Cyclosporiasis — United States, May–June 2022



Cyclosporiasis illnesses are reported year-round in the United States. However, during the spring and summer months there is often an increase in cyclosporiasis acquired in the United States (i.e., “domestically acquired”). The exact timing and duration of these seasonal increases in domestically acquired cyclosporiasis can vary, but reports tend to increase starting in May. In previous years the reported number of cases peaked between June and July, although activity can last as late as September. The overall health impact (e.g., number of infections or hospitalizations) and the number of identified clusters of cases (i.e., cases that can be linked to a common exposure) also vary from season to season. Previous U.S. outbreaks of cyclosporiasis have been linked to various types of fresh produce, including basil, cilantro, mesclun lettuce, raspberries, and snow peas.

At a Glance
  • Illnesses: 61
  • Hospitalizations: 6
  • Deaths: 0
  • States reporting cases: 13

CDC, along with state and federal health and regulatory officials, monitor cases of cyclosporiasis in the United States in the spring and summer months to detect outbreaks linked to a common food source. However, many cases of cyclosporiasis cannot be directly linked to an outbreak, in part because of the lack of validated laboratory “fingerprinting” methods needed to link cases of Cyclospora infection. Officials use questionnaires to interview sick people to determine what they ate in the 14-day period before illness onset. If a commonality is found, CDC and partners work quickly to determine if a contaminated food product is still available in stores or in peoples’ homes and issue advisories.

Latest Information

  • This is the first monthly report on the number of domestically acquired cyclosporiasis illnesses with onset on or after May 1, 2022. Cases continue to be reported.
  • As of June 28, 2022, 61 laboratory-confirmed cases of cyclosporiasis in people who had no history of international travel during the 14-day period before illness onset have been reported to CDC by 13 states since May 1, 2022.
    • The median illness onset date is May 31, 2022 (range: May 3–June 20, 2022).
    • At least 6 people have been hospitalized; no deaths have been reported.

USA – Will There Be a Cyclospora Outbreak in the U.S. This Summer?

Food Poisoning Bulletin

Will there be a cyclospora outbreak in the United States this summer? There have been multiple cyclospora outbreaks in the past nine years, including in 2013, 2014, 2015, 2016, 2017, 2018, 2019, 2020, and 2021. This year may be no exception.

In the past, Cyclospora outbreaks have been linked to fresh produce, including cilantro, raspberries, basil, mesclun, vegetable trays, bagged salad mixes, and snow peas. The cyclospora parasite is transmitted through human feces. The oocyst must mature, or sporulate, outside of the body before it becomes infectious. This infection is not passed person-to-person.

It is very difficult to protect yourself against this parasite, since it can cling to produce, especially produce such as leafy greens and herbs, and is not easily washed or rinsed off. And since most of the foods it contaminates are eaten without being heated, there is no kill step to destroy the parasite.

Research – What Is Cyclospora?

Food Poisoning News

Cyclospora cayetanensis is a protozoan parasite that causes the diarrheal illness known as cyclosporiasis. People acquire this infection by consuming food or water contaminated with feces containing Cyclospora. Cyclosporiasis was not previously a reportable disease in the U.S., so its rise in prevalence is due in large part to the increased availability of tests that can detect Cyclospora. It is now a nationally notifiable disease, so physicians are required to report cases of this infection.

The first three cases of cyclosporiasis were reported in 1977 and 1978, but the parasite that was causing the illnesses could not at that time be identified as Cyclospora cayetanensis; it was not until 1979 that the correct identification was made.

Norway – Cyclospora, Toxoplasma and Cryptosporidium detected in berries sold in Norway

Fresh Plaza

water contamination

Cyclospora, toxoplasma and cryptosporidium have been detected in berries sold in Norway. Blueberries, strawberries and raspberries were tested for Echinococcus multilocularis, Toxoplasma gondii, Cyclospora cayetanensis and Cryptosporidium. Raspberries were the most contaminated, followed by strawberries and blueberries. Strawberries and raspberries were mainly tainted with Cryptosporidium, while blueberries were contaminated mostly with Cyclospora. Toxoplasma and Cyclospora were frequently found in raspberries, according to the study published in the journal Food Microbiology.

However, researchers said it was important to note that only DNA was detected, so there is no certainty that the intact, infective stages of parasites were present, and there is no information on viability.

In Norway, because of the short growing season, many berries come from abroad, with more than 13,000 tons imported in 2020. In total, 86 berry samples were from domestic fruit while others came from countries such as Peru, Morocco, Chile, Netherlands, Portugal and Poland.

Researchers said that while findings are cause for some degree of concern for Norwegian food safety authorities, encouraging consumers to wash berries before consumption could reduce the risk of infection.

Research -Surveillance of berries sold on the Norwegian market for parasite contamination using molecular methods

Science Direct

water contamination

The risk of foodborne parasite infection linked to the consumption of contaminated fresh produce has long been known. However, despite epidemiological links between the outbreaks and contaminated berries, few studies have assessed the magnitude of parasite contamination on fresh produce sold in Europe. The present study was aimed to address the knowledge gap on parasite contamination of berries sold in Norway. Samples of blueberries, strawberries, and raspberries were analysed by multiplex qPCR for detection of Echinococcus multilocularisToxoplasma gondii, and Cyclospora cayetanensis. In addition, a simplex qPCR method was employed for detecting contamination of the berries with Cryptosporidium spp. A total of 820 samples of berries, each of around 30 g (274 samples of blueberries, 276 samples of raspberries, and 270 samples of strawberries), were analysed. We found an overall occurrence of 2.9%, 6.6%, and 8.3% for T. gondii, C. cayetanensis, and Cryptosporidium spp., respectively, whereas E. multilocularis was not detected from any of the samples investigated. Strawberries and raspberries were most often contaminated with Cryptosporidium spp., whereas blueberries were contaminated mostly with C. cayetanensis. Detection of parasite contaminants on fresh berries indicates the need for a system to ensure the parasitological safety of fresh berries.