A cloth-based hybridization array system for rapid detection of the food- and waterborne protozoan parasites Giardia duodenalis, Cryptosporidium spp. and Toxoplasma gondii

Molecular characterization of Giardia duodenalis, Cryptosporidium spp., and Entamoeba spp. infecting domestic and feral/stray cats in Jordan

This study aimed to carry out a molecular screening for the presence of Giardia, Cryptosporidium, and/or Entamoeba in the feces of pet and stray/feral cats in Jordan. G. duodenalis was found in 27.9% (95% CI, 23.2-32.9) of the 348 sampled cats overall; E. histolytica was found in only 0.6% (95% CI, 0.1-2.1) of the cats, while none of the sampled cats had Cryptosporidium infections. The infection rate of G. duodenalis among indoor cats (32.3%) did not differ significantly from that among outdoor cats (24.1%). There were significantly more infections (p = 0.0004) geographically in the cold semiarid areas (67%) than in the cold desert areas (24%). Multilocus sequence typing analysis of amplicons based on the bg, tpi, and gdh genes revealed that the majority of G. duodenalis infections were zoonotic assemblage B (65.9%; 64 of 97 positive samples); followed by feline-specific assemblage F (18.5%, 18/97); cattle-specific assemblage E (5.2%, 5/97); and then assemblage C that was shared with canids (1.0%; 1/97). Within Giardia isolates, a substitution mutation (A/G) was found at position 297 of the complete protein coding sequence (cds) of tpi-assemblage B, which may represent a new spreading mutation within this gene among the cat population in Jordan. The results of the present study suggest that close human-cat interactions could play a role in zoonotic transmission of Giardia, but further research is needed to determine the possible contribution of cats to the transmission of other protozoa to humans.

Molecular Identification of Protozoan Sarcocystis in Different Types of Water Bodies in Lithuania

Representatives of the genus Sarcocystis are unicellular parasites having a two-host life cycle and infecting mammals, birds, and reptiles. Until now, Sarcocystis spp. have been mainly investigated in definitive and intermediate hosts. Only a few studies have been conducted on the detection of Sarcocystis parasites in water samples. The aim of this research was to examine whether the prevalence of Sarcocystis spp. parasitizing farm animals varies in different types of water bodies. Water samples (n = 150) were collected from the entire territory of Lithuania, dividing water bodies into five groups (lakes, rivers, ponds/canals, swamps, and the inshore zone of the territorial Baltic Sea area). One-liter samples were filtered and subsequently analyzed using nested PCR. At least one of the analyzed Sarcocystis spp. (S. arieticanis, S. bertrami, S. bovifelis, S. capracanis, S. cruzi, S. hirsuta, S. miescheriana, and S. tenella) was determined in all examined samples from water bodies. No significant difference in Sarcocystis spp. prevalence between different types of water sources was detected. Our research proved that selecting appropriate primers is important for the accurate identification of parasites in samples collected from water bodies.

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.

Detection of Cryptosporidium spp. and Giardia spp. in Environmental Water Samples: A Journey into the Past and New Perspectives

Among the major issues linked with producing safe water for consumption is the presence of the parasitic protozoa Cryptosporidium spp. and Giardia spp. Since they are both responsible for gastrointestinal illnesses that can be waterborne, their monitoring is crucial, especially in water sources feeding treatment plants. Although their discovery was made in the early 1900s and even before, it was only in 1999 that the U.S. Environmental Protection Agency (EPA) published a standardized protocol for the detection of these parasites, modified and named today the U.S. EPA 1623.1 Method. It involves the flow-through filtration of a large volume of the water of interest, the elution of the biological material retained on the filter, the purification of the (oo)cysts, and the detection by immunofluorescence of the target parasites. Since the 1990s, several molecular-biology-based techniques were also developed to detect Cryptosporidium and Giardia cells from environmental or clinical samples. The application of U.S. EPA 1623.1 as well as numerous biomolecular methods are reviewed in this article, and their advantages and disadvantages are discussed guiding the readers, such as graduate students, researchers, drinking water managers, epidemiologists, and public health specialists, through the ever-expanding number of techniques available in the literature for the detection of Cryptosporidium spp. and Giardia spp. in water.