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Innovations in Noninvasive Instrumentation and Measurements
Published in Robert B. Northrop, Non-Invasive Instrumentation and Measurement in Medical Diagnosis, 2017
Applications of the SFCM in medical diagnosis include examination of blood drops for anomalies. Blood contains erythrocytes (RBCs), leukocyctes (WBCs), platelets, and can have things that shouldn't be there, such as free bacteria and blood-borne parasites. Protozoans of particular interest include Plasmodium (∼200 species) (P. falciparum, P. vivax, P. knowlesi, and P. malariae cause malaria in humans). The spirochete bacterium, Borrelia burgdorferi, causes Lyme disease, and the spirochete bacterium, Treponema pallidum (an obligate intracellular parasite), causes syphilis. (There are ∼31 Treponema spp.) Also parasites such as Schistosoma (26) spp. (S. mansoni, S. intercalatum, S. haematobium, S. japonicum, and S. mekongi) can infect humans and cause schistosomiasis. The parasitic nematode, Trichinella (8) spp. (T. spiralis, T. nativa, and T. britovi), can infect humans and cause trichinosis. The parasite Trypanosoma brucei and T. brucei gambiense are responsible for East and West African Sleeping Sickness, respectively. The disease known as babesiosis is caused by a protozoan blood parasite, Babesia (14) spp. B. microti, B. duncani, and B. divergens infect human erythrocytes. The physical symptoms of babesiosis are often confused with Malaria. Babesiosis is spread by tick bites.
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Published in Jamie Bartram, Rachel Baum, Peter A. Coclanis, David M. Gute, David Kay, Stéphanie McFadyen, Katherine Pond, William Robertson, Michael J. Rouse, Routledge Handbook of Water and Health, 2015
Timothy R. Julian, Kellogg J. Schwab
There are three groups of helminths that are parasitic to humans: tapeworms, roundworms, and flukes. Tapeworms (e.g., Taeniaspp., Hymenolepis spp., Echinococcusspp.) reside in the intestinal tract and can cause discomfort, diarrhea, and/or anemia. Flukes parasitize blood (i.e., blood flukes) and/or organ tissue (i.e., tissue flukes). Clonorchis sinesisand Paragonimus westermaniare two genera of foodborne tissue flukes that infect the liver and lungs, respectively. Clonorchis sinesisinfection can cause nausea, diarrhea, weight loss, jaundice, bacterial infections, inflammation, and cancer. Paragonimus westermani symptoms may include abdominal pain, diarrhea, fever, and/or hives. In severe cases, Paragonimus westermani infection causes headaches, vomiting, seizures, and death if left untreated. Roundworms are distinguished from both tapeworms and flukes by the presence of a tubular digestive system. Ascaris lumbricoides, a type of roundworm, compromises nutritional status and can cause anemia, stunting, and cognitive deficiencies. A second type of roundworm, Trichinellaspp., is one of the most common foodborne helminths. Symptoms of infection include nausea, vomiting, sweating, diarrhea, and/or fever. If left untreated, infections can lead to intense muscular pain, difficulty breathing, heart damage, kidney malfunction, and/or death as the parasite migrates from the site of first infection (typically the intestinal mucosa) to other host organs.
Foodborne Illness
Published in Gary S. Moore, Kathleen A. Bell, Living with the Earth, 2018
Gary S. Moore, Kathleen A. Bell
Parasites are organisms that require another animal (host) to complete their life cycle. Organisms such as Entamoeba histolytica or Cryptosporidium parvum require only one host, they are shed in the feces, and infection occurs by consuming food or water contaminated with these feces. Trichinella spiralis, on the other hand, causes infection in those who eat meat infested with the cyst of the organism. In the case of Trichinella, the organism requires two hosts, the intermediate host (pig) that houses the cyst, and the definitive host (human), where the organism develops into an adult and is shed in the feces.
Developing mitochondrial DNA field-compatible tests
Published in Critical Reviews in Environmental Science and Technology, 2022
Bidhan C. Dhar, Christina E. Roche, Jay F. Levine
Gel electrophoresis is frequently used to detect endpoint PCR products created during enzymatic enhancement. Gel electrophoresis, however, is impractical under field conditions and paper-based alternatives have been developed that allow DNA amplification to be performed at a constant temperature. For instance, Ruchira and coworkers (2018) targeted the human mitochondrial cytb gene on a FTA card prior to detection using a conventional PCR assay. The field utility of filter-paper based LAMP assays was demonstrated by the detection of human malaria parasite (Plasmodiium) mtDNA sequences using fluorescently labeled probes (Aydin-Schmidt et al., 2014). The detection limit was found to be ≤2 parasites per µL. The paper-based LAMP assay was further improved by the use of a SYBR Green dye that enhanced visual mtDNA detection (Tao et al., 2011). The LAMP assay was sensitive and specific, and the assay results concurred with a laboratory-based nested PCR assay. Similarly, Song and coworkers (2014) developed a cellulose filter paper-based assay for the visual detection of human and dog genomic DNA and mtDNA. Capillary action was used to facilitate DNA sample movement through the filter paper and accommodated target hybridization with the complementary internal probe and the capture of oligonucleotide sequences. A color change facilitated reading test results. A comparable LAMP assay was developed that used a divalent metal ion indicator, calcein, to detect cow and sheep mtDNA targeting the COX1 and cytb genes (Ma et al., 2016). Yang and coworkers (2017) developed a complete on-site field protocol for sampling, DNA isolation, and LAMP assay processing for environmental wastewater monitoring. This low-cost rapid procedure accommodated filtration of large solids, cell lysis, MB extraction, and LAMP reaction mixing. Biotin and fluorescein isothiocyanate labeled primers targeting a human mitochondrial gene were used in the LAMP reaction and positive amplification products were observed on a lateral flow device (Ustar Biotech Co., Ltd., Hangzhou, China). Li and coworkers (2019) developed a sensitive RPA assay that used a lateral flow strip for detecting Trichinella spp. (Li et al., 2019).