Category Archives: Parasite

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.

Ireland – EPA finds issues with Fermoy water supply – Cryptosporidium

Irish Examiner


Cryptosporidium had been detected in the public water supply in Fermoy in November last year

The public water supply to the north Cork town of Fermoy could be at risk and placed on a list of water treatment plants needing corrective action, according to the State environmental watchdog.

The Environmental Protection Agency has warned Irish Water that Fermoy’s water treatment plant could be placed on its Remedial Action List which would require the utility to complete an action programme to address problems with the supply.

It follows an audit by EPA inspectors carried out on the facility last November to check if it was providing clean and wholesome water to households and businesses.

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

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.

CPS – Funded Research Projects 2022 – Cyclospora



Cyclospora cayetanensis monitoring in agricultural water

The parasite Cyclospora Cayetanensis is producing illness in people consuming infected produce. Because this pathogen is in very low concentrations on actual produce, which makes it close to impossible to detect, and for prevention reasons, it is more effective to check for its presence in irrigation water, from where it is typically transferred on produce. However, even in water, this parasite is very difficult to detect. It only can be detected by lengthy molecular laboratory procedures such as PCR. One major problem for scientists to develop better and faster detection methods is the fact that there is no antibody or other recognition molecule that would be able to bind to the surface of this intact parasite.

We propose to design and synthesize, for the first time, aptamers, molecules that will be able to bind to intact Cyclospora Cayetanensis oocysts, and use them to design simple paper based colorimetric tests that can detect it in the field without the need of sample preparation or specialized laboratories. The paper based test will turn from pink to purple to indicate the water sample being tested is positive for this parasite, making this a very simple and easy to use detection method for Cyclospora Cayetanensis.


AFECCT: Assessing filtration efficacy for Cyclospora control

The reputation of growers and the health of consumers suffer when people contract foodborne illness from fresh produce contaminated with Cyclospora cayetanensis. Because filtration has been established as effective in concentrating parasites for environmental surveillance, we propose to establish how effectively filters remove such parasites from irrigation water. To achieve this, we will first conduct a series of filtration experiments using abundant parasites (of chickens) that pose no risk to the study team. We’ll then assess how well these filters reduce water contamination with Cyclospora. We will also determine whether any parasites surviving filtration are harmed in the process. We hope these findings will directly benefit growers seeking tools to mitigate risk, and hasten future research progress by validating a needed surrogate system for studying other interventions against this dangerous and enigmatic human parasite.


Research – Main Groups of Microorganisms of Relevance for Food Safety and Stability


Microbiology is important to food safety, production, processing, preservation, and storage. Microbes such as bacteria, molds, and yeasts are employed for the foods production and food ingredients such as production of wine, beer, bakery, and dairy products. On the other hand, the growth and contamination of spoilage and pathogenic microorganisms is considered as one of the main causes to loss of foodstuff nowadays. Although technology, hygienic strategies, and traceability are important factors to prevent and delay microbial growth and contamination, food remains susceptible to spoilage and activity of pathogen microorganisms. Food loss by either spoilage or contaminated food affects food industry and consumers leading to economic losses and increased hospitalization costs. This chapter focuses on general aspects, characteristics, and importance of main microorganisms (bacteria, yeasts, molds, virus, and parasites) involved in food spoilage or contamination: known and recently discovered species; defects and alterations in foodstuff; most common food associated with each foodborne disease; resistance to thermal processing; occurrence in different countries; outbreaks; and associated symptoms.