Sucrose Flotation Method Research Articles

Depth distribution of plant-parasitic nematodes on bentgrass golf greens in Missouri and Indiana.

Control of plant-parasitic nematodes (PPNs) on golf putting greens with nematicides is dependent on the seasonal occurrence and depth distribution of target PPN populations. This study aimed to determine if plant-parasitic nematode populations on golf course putting greens in Missouri and Indiana peaked at a targetable depth at a specific time in the year, focusing primarily on lance (Hoplolaimus spp.) and root-knot (Meloidogyne spp.) nematodes. To elucidate species diversity in the region, rDNA from a subset of lance and root-knot nematodes was sequenced and analyzed, with additional micromorphology of a lance nematode assessed in scanning electron micrographs (SEM). Soil samples were taken to a depth of 25 cm and stratified into 5 cm increments during April, June, August and October at seven sites across Missouri, three in the Kansas City metro of Kansas in 2021 and in ten sites across Indiana in 2022. Samples were stratified in five-centimeter increments and aggregated for a total of 100 cm3 of soil at each depth for each sampling. Samples were processed using a semi-automatic elutriator followed by the sucrose-flotation method, and populations were counted using a hemocytometer and recorded. For molecular characterization, rDNA was extracted and analyzed from 31 individual lance nematodes from one site in Missouri and eight sites in Indiana, and 13 root-knot nematodes from nine sites across Indiana. A significant interaction occurred between sampling month and depth for lance and ring nematodes Missouri/KS, with both PPN populations peaking at the 0-5 cm depth during October, which is well after most targeted nematicide applications are applied. Ring nematodes in Indiana did not follow this trend and were most abundant in August at a depth of 0-5 cm. No significant interaction between depth and month occurred for lance or root-knot nematodes in Indiana, or root-knot nematodes in Missouri/KS. Hoplolaimus stephanus and H. magnistylus were the lance species identified on golf greens, and Meloidogyne naasi, M. graminicola and M. marylandi were the root-knot species identified. Scanning-electron micrographs confirmed morphological characteristics unique to H. stephanus.

High prevalence of Cryptosporidium infection in Iranian patients suffering from colorectal cancer

The present investigation was designed to study the prevalence of cryptosporidiosis in the colorectal cancer patients compared to the healthy subjects. The present descriptive case-control study was performed on 174 subjects including 87 healthy people and 87 patients with colorectal cancer attending to general hospitals in Lorestan Province, Western Iran, during October 2019–August 2020. A fresh stool specimen was collected from each subject in a sterile labeled container. The collected stool samples were concentrated using the sucrose flotation method and then prepared for Ziehl-Neelsen staining for microscopic examination. All samples were also tested using the Nested-PCR assays by amplifying the 18S rRNA gene for the presence of Cryptosporidium DNA. Demographic and possible risk factors such as age, gender, residence, agriculture activity, history of contact with livestock, consumption unwashed fruits/vegetables, and hand washing before eating were investigated in all the studied subjects using a questionnaire. Of the 87 patients with colorectal cancer, 37 (42.5%) had Cryptosporidium infection. A significant difference (p < 0.001) in the prevalence of Cryptosporidium spp. infections among the participants in the case and control (11, 12.6%) groups was observed. We found that cryptosporidiosis was not linked with age, gender, hand washing, agriculture activity, and history of contact with livestock in the colorectal patients. However, residence in urban areas was significantly associated with the prevalence of cryptosporidiosis. The 18 s rRNA gene of Cryptosporidium in 48 samples was successfully amplified by the Nested-PCR. Based on the obtained findings, Cryptosporidium spp. infections were observed significantly more frequently in the patients with colorectal cancer in comparison with the healthy individuals. It is suggested to carry out similar studies in various parts of Iran with larger sample sizes and further parasitological tests.

Gastrointestinal parasites in domestic cat (Felis catus Linnaeus, 1758) in Oran, Algeria: emergent zoonotic species and associated risk factors

Among protozoa and helminths parasites of the cat’s digestive tract, some constitute a problem for public health, due to their zoonotic potential. An identification of gastrointestinal parasites is therefore necessary to control their distribution. The aims of the present study were to determine prevalence of gastrointestinal parasites in domestic cat in Oran, western Algeria, and to identify risk factors associated with parasitism. One hundred and two fecal samples were collected from 102 domestic cats during period from February to July 2021, and analyzed using two coprological technics, sucrose flotation and Ritchie method. Age, sex, breed, eating habits and lifestyle of each cat were recorded to identify risk factors by using a bivariate test, Chi2 test. Sixty-two (60.8%) cats were infected with at least one intestinal parasite. Six species were identified: Toxocara cati (43.1%), Dipylidium caninum (15.7%), Toxascaris leonina (7.8%), Cystoisospora rivolta (5.9%), Giardia duodenalis (2%) and Cystoisospora felis (1%). The occurrence of co-infections was observed in 13.7% of cats. Young age, hunting behavior, outdoors access and raw chicken meat consummation are identified as factors significantly linked to contamination by gastrointestinal parasites. The findings showed that there is a significant infestation of domestic cats by the parasitic helminths, such as Toxocara cati, wich has a major public health impact. This suggests that immediate action may be carried to reduce infection rates in cats by implementing preventive antiparasitic treatments and to sensitize cats owners about zoonotic diseases risk.

Prevalence of Intestinal Parasites and Associated Risk Factors in Chepang Community of Saktikhor Area, Chitwan, Nepal

Abstract: Objective: Pathogenic species of protozoa and helminth cause intestinal parasitosis, which continues to be a significant community well-being issue in many regions of the world, especially in pastoral regions of developing countries like Nepal. The study focused on determining the prevalence of intestinal parasitic infections and the associated risk factors among the people of the Chepang community of the Saktikhor area in the Chitwan district. Materials and Methods: A transversal study was conducted between May 2017 and October 2017, with a total of 125 participants. The fecal samples were examined using a wet media (saline media, iodine preparation), concentration and sucrose flotation method. The association between risk factors and parasitic prevalence was evaluated using the Pearson’s chi-square test. Results: The general prevalence of intestinal parasite infection was 52%. Infections with soil-borne helminth were more common than those with cestodes and protozoa. Common intestinal parasites included Ascaris lumbricoides (69.23%), Trichuris trichiura (9.23%), Hookworm (7.69%), Strongyloides stercoralis (4.62%), Hymenolepis nana (6.15%), Taenia sp. (6.15%), and Entamoeba coli (9.23%). High prevalence of infection was observed among male (53.96% ) participants and those aged over 20 years (69.44%). Pearson's chi-square test revealed a substantial relationship between prevalence of parasite and age group (P=0.0452), hand washing material (P&lt;0.001) and preference for defecation site (P&lt;0.001). Conclusion: Hence, a heavy occurrence of intestinal parasites within the Chepang community is particularly evident. There is a need for increased emphasis on intrusion, which can be achieved by improving personal hygiene and sanitation of participants and constructing proper sanitary toilets to prevent the spread of parasitic infections. Keywords: IPIs, Helminth, Cestode, Protozoan, HMP, NTDs, Community, Prevalence.

Rate of Soil Contamination by Soil Transmitted Helminths in Relation to the Awareness Status of Pupils in Primary Schools of Penka-Michel, West-Cameroon

Background: Soil transmitted helminth (STH) infections disproportionately affect poor populations in tropical and subtropical parts of the world. They contaminate soil and pupils are mostly at risk of these infections due to their soil related habits. Aims: to assess pupils’ knowledge, attitude and practice in relation to the rate of soil contamination in public primary schools. Methods: Structured questionnaires were administered to 729 consenting participants to obtain information on their awareness status of STH infections. A total of 552 soil samples were collected around toilets, classrooms backyards and playground in 23 public schools randomly selected in Penka-Michel subdivision and examined for the presence of STH eggs using the sucrose flotation method. Results: up to 80% of respondents do not actually know how to avoid getting infected with worms. About 50% of pupils do not actually wash their hands after defecating or wash their fruits/vegetables before eating. Pupil’s nails were mostly untrimmed (74.1%). 77.1% declared they always defecate out of the toilets when they are in school. Out of 552 soil samples examined, 97 (17.6%) were contaminated by Ascaris sp, Trichuris sp, Toxocara sp, Capillaria sp, Cooperia sp, hokworms and Nematodirus sp. Soil from around toilets were significantly more contaminated with Ascaris sp and Trichuris sp eggs. Soil contamination was also significantly associated with absence of water during class hours, unhygienic conditions of toilets, and lack of school perimeter fence. Overall 65% of schools selected showed a low level of hygiene. Conclusion: Pupils of these schools played a major role in the contamination of their environment. Therefore, in order to prevent the STHs transmission cycles in school environment and possibly in pupils, it is necessary to develop specific sustainable intervention programs.

Extracellular vesicles derived from postmortem human brain tissue contain seed‐competent C‐terminal tau fragments, and provide proteomic clues to the identity of selectively vulnerable cell populations in human tauopathies

AbstractBackgroundPathological tau is spread along anatomically connected networks, originating in areas containing particularly vulnerable cell populations. It is hypothesized that tau is released and spread as free tau, or via extracellular vesicles (EVs) that include exosomes (30‐150 nm), microvesicles (100‐1000 nm), and apoptotic bodies (1000‐5000 nM). While a variety of different EV tau species have been identified in tissue, cells, and bio‐fluids, EV tau has not yet been described from human post‐mortem tauopathy brain tissue.MethodUsing a differential centrifugation and sucrose flotation method described by Perez‐Gonzalez et al., EVs were isolated from post‐mortem human frontal cortex tissue blocks from Alzheimer’s Disease (AD), Corticobasal Degeneration (CBD), and Control cases (BA9, n=4/group).ResultElectron microscopy (EM) confirmed the presence of vesicles with characteristic shape and size of exosomes and microvesicles. As demonstrated by immunoblotting, EV tau from tauopathy cases contains very little full‐length tau, but is specifically enriched in tau fragments of 10‐15 and 30‐35 kDa. EVs from control cases contain low levels of full‐length tau, and no tau fragments. EV tau fragments are sarkosyl‐insoluble, protected by the lipid membrane of the vesicle, and are seed‐competent (RD‐tau biosensor FRET seeding assay, seeding of primary neurons, and significant spread of AT8+ tau in EV‐injected PS19 mouse hippocampi). Epitope mapping and mass spectrometry sequencing confirm the presence of C‐terminal tau fragments, and further proteomic analyses confirm the identity of EVs as secreted vesicles. Together, these data provide the first clues to tauopathy‐specific proteomic signatures of EVs, and identify exosome components derived from the most vulnerable cell populations. This work complements the biomarker literature showing that N‐terminal regions of tau are secreted into the cerebral spinal fluid, while C‐terminal regions are retained in the brain.ConclusionThe identification of a seed‐competent species encased in a vesicle that readily fuses with cell membranes confirms that EVs are likely a significant mediator of pathological tau spread in the human brain. Our continued investigation of EV tau cryo‐EM structure, and of EV tau‐containing vesicles will focus on identifying novel immunological targets for pathological tau, and the vesicles that facilitate its spread.

Combined Molecular and Lectin Binding Assays to Identify Different Trichostrongyle Eggs in Feces of Sheep and Goats from Egypt

Trichostrongyles are common causes of parasitic gastroenteritis in sheep and goats worldwide. Accurate identification of these nematodes to the genus and/or species level is important for therapy selection and control strategies. In the present study, molecular and egg-lectin binding approaches were employed to identify the most economically important trichostrongyles circulating in sheep and goat herds from six districts in Dakahlia governorate, Egypt. Fecal samples from 653 and 205 goats reared within 17 herds were collected and tested for the trichostrongyle eggs using the modified Wisconsin sucrose flotation method. For identification of the trichostrongyle(s) present, eggs from 75 (63 sheep and 12 goats) samples which had high egg count (EPG) and pooled eggs (n = 19 pools, 15 sheep and 4 goats) from samples with moderate or low EPGs were examined. Molecular examination was conducted amplifying the ITS2 region of the rDNA for six different trichostrongyles in individual PCR reactions. For egg-lectin bindings, 4 fluorescently-labeled specific lectins were used; peanut agglutinin (PNA) for Haemonchus contortus, Aleuria aurantia agglutinin (AAL) for Trichostrongylus species, Lens culinaris agglutinin (LCA) for Teladorsagia circumcnicta and Lotus tetragonolobus lectin (LTL) for Cooperia species. Fourteen (82.3%) herds were found infected, of which trichostrongyle eggs were detected in fecal samples of 26.5% (173/653) of sheep and 10.2% (21/205) of goats. Results of the PCR and lectin bindings were compatible and 4 trichostrongyles were detected: H. contortus, T. circumcincta, Trichostrongylus axei and Trichostrongylus colubriformis. Haemonchus contortus eggs were found in all the infected herds, and as the single species in 21 and 5 of sheep and goat samples, respectively. Lectin stained smears demonstrated the dominance of H. contortus eggs over eggs of the other detected trichostrongyles. Eleven herds were found infected with T. axei as the second most prevalent trichostrongyle; however, few AAL-stained eggs were noticed in the positive samples. Mixed infections were frequently detected as H. contortus-T. axei combination. Infections with T. circumcincta were noted in sheep samples from two herds, but not in any sample from the goats. No Ostertagia leptospicularis, Cooperia curticei or Nematodirus species were noted among the tested samples. This is the first molecular and lectin binding survey to determine the species composition of trichostrongyles infecting sheep and goats from Egypt. Haemonchus contortus plays the principal role in small ruminant trichostrongylosis in Egypt. Egg-lectin staining shows promise for future for its application in routine diagnosis as a rapid and simple technique. Findings of the earlier reports from Egypt are tabulated and reviewed.

High Parasitic Contamination of Soil Samples in the North of Iran: A Potential Risk of Parasitic Infection for Tourists.

Soil-transmitted parasites (STPs) are significant intestinal parasites that infect humans and animals and impose considerable burdens on human society and animal husbandry industries. Therefore, the present study aimed to determine the prevalence of parasitic elements of soil samples collected from the north of Iran. A total of 256 soil samples were collected from public parks, public places, vegetable gardens, sand heaps, and shadow areas near houses in the north of Iran and examined using the sucrose flotation method. Out of 256 examined samples, 131 (51.2%) showed parasitic contamination, including larvae (43%), oocysts (14.1%), and different eggs (6.6%). According to the results, the most and least common parasites observed in the samples were larvae (43%), as well as Toxascaris leonina, and Trichuris trichiura (0.4%), respectively. Moreover, the most and least contaminated locations were sand heaps (62.5%) and shadow areas near houses (45.6%), respectively. Regarding cities, Behshahr (68.3%) and Sari (67.5%) had the highest contaminated soil samples, whereas Chalus (37.5%) showed the lowest contamination. On the other hand, rural samples showed more contamination compared to urban areas (P< 0.05). The findings of the present study indicate that the overall prevalence of STPs in examined areas and highly contaminated soil samples can be considered as a potential source of human contamination particularly tourists with STPs.

Prevalence of Toxocara spp. Eggs in Soil Samples of Public Parks of Ilam City, Iran

Introduction: Toxocariasis, also known as Visceral Larva Migrans (VLM) syndrome, is a parasitic disease caused by the ascaris larva migrans of dogs and cats, especially Toxocaracanis. The eggs of this parasite enter the human body through contaminated food, water, and soil. Aim: To determine the prevalence of Toxocara spp. eggs in the soil of public parks in Ilam city, Iran. Materials and Methods: In this descriptive cross-sectional study, 40 soil samples (100 grams per sample from the depth of 3 to 5 cm) were randomly collected from 10 public parks of Ilam city in the summer season of 2018. After washing, grinding, and separating large particles from the samples, parasitic eggs were isolated using 150-micron filters and sucrose flotation method. The data was analysed using SPSS 20 software. Results: Five of ten parks (50) were contaminated with Toxocara spp. eggs. From 40 soil samples collected from the public parks, 16 (40) were contaminated with Toxocara spp. eggs. Most of the contaminated samples were collected from walking and flowering areas in all the parks. Microscopic studies showed an average of 1-4 Toxocara spp. eggs per microscopic field in each sample indicating 4 to16 eggs per 100 grams of soil in each contaminated park. Conclusion: Due to the high level of contamination with Toxocara spp, eggs in Ilam city parks, it is necessary to prevent dogs and cats from entering to lawns and playgrounds in public parks by fencing.

The Study of Soil Contamination by Toxocara spp. Eggs in Different Areas of Chaharmahal and Bakhtiari Province, Southwest Iran

Background and aims: Toxocariasis caused by the larvae of Toxocara spp. is a zoonotic infection with global distribution that is considered an important health problem in the humans. The soil is regarded as the main source of the transmission of Toxocara infection to susceptible hosts. This study investigated the existence of Toxocara spp. ova in rural and urban public areas of Chaharmahal and Bakhtiari province. Methods: A total of 180 soil samples were randomly collected from 74 public places from urban and rural areas of nine counties of Chaharmahal and Bakhtiari province during May to September, 2017. The samples were examined for Toxocara spp. eggs by the modified sucrose flotation method. Results: The contamination rate of the soil samples with Toxocara spp. ova varied within 0%-18.1% in different counties. Overall, 9 (5%) out of 180 examined soil samples were found positive for Toxocara spp. ova. Of nine investigated districts, Toxocara spp. ova were observed in four counties and the highest rate of soil contamination was found in Farsan county with 18.1%. Finally, the prevalence of Toxocara spp. eggs was more in the rural areas (6.7%) compared to the urban ones (3.3%). Conclusion: This study was the first investigation regarding the contamination of Toxocara spp. eggs in the soil of public places in rural and urban areas of Chaharmahal and Bakhtiari province. According to the results, the rate of soil contamination in this region was lower compared with the other parts of Iran. Therefore, a further study is required to determine factors that may be involved in the distribution of Toxocara spp. in different areas of this province.

First report of Sarcocystis pilosa sporocysts in feces from red fox, Vulpes vulpes schrencki, in Hokkaido, Japan.

Sarcocysts of various Sarcocystis spp. are highly prevalent in wild sika deer, Cervus nippon yesoensis, in Hokkaido, Japan, and four species have been identified based on morphological and molecular characteristics: S. ovalis, S. pilosa, S. tarandi-like, and S. truncata-like. The definitive hosts of S. ovalis are corvids, but the hosts of the other species have not yet been identified. Aiming to determine the definitive hosts of these species, we collected 65 red fox (Vulpes vulpes schrencki) fecal samples in eastern Hokkaido and examined them for fecal sporocysts using a modified sucrose flotation method. One fecal sample contained typical Sarcocystis sporocysts, which were identified as S. pilosa based on 18S ribosomal RNA and cytochrome c oxidase subunit I gene sequences. This is the first identification of S. pilosa sporocysts in the wild. These findings indicate that red foxes serve as a definitive host of S. pilosa, and that red foxes constitute a source of S. pilosa infection for deer in Hokkaido.

Prevalence and associated risk factors of Cystoisospora belli and Cyclospora cayetanensis infection among Iranian patients with colorectal cancer.

From among intestinal parasites, coccidian intestinal parasites such as Cystoisospora belli (previously known as Isospora belli), and Cyclospora cayetanensis are well-known as opportunist parasites, particularly in patients with cancer. This study assessed the prevalence of C. belli and C. cayetanensis in patients with cancer in Lorestan Province, Southwest of Iran. This cross-sectional descriptive study was conducted on 87 patients with colorectal cancers, referred to the general hospitals of Lorestan from October 2017 to August 2018. A fresh stool specimen was collected from each subject in a sterile labeled container. The collected stool samples were concentrated through sucrose flotation method and then prepared for Ziehl-Neelsen staining for microscopic examination. Demographic and possible risk factors such as age, sex, education, residence, and unwashed vegetable/fruit consumption were collected by an applied questionnaire. Out of the 87 patients with colorectal cancer, eight (9.2%) were found positive for C. belli and C. cayetanensis infections, with five (5.74%) and three (3.44%) patients positive for C. belli and C. cayetanensis infections, respectively. Results also showed that sex and unwashed vegetable/fruit consumption were significantly associated with the prevalence of these parasites (p < 0.01). The findings revealed the considerable prevalence of C. belli and C. cayetanensis in patients with colorectal cancers. It is therefore essential for gastrointestinal specialists to pay special attention to the prevalence of coccidian parasites in patients with colorectal cancer.

Prevalence and genetic diversity of Toxoplasma gondii oocysts in cats of southwest of Iran

Abstract Objective Contamination of soil and water with infected oocysts have an important role in both animals and humans toxoplasmosis. Cats shed oocytes by their feces that can survive in environment such as moist soil, warm and humid weather for months and even years. The present study designated to molecular detection of Toxoplasma gondii oocysts in stool samples obtained from cats in Ahvaz, southwest of Iran. Methods Initially, 486 stool samples were randomly collected from cats. After sucrose flotation method, the DNA was extracted and PCR was carried out using the amplification of the B1 gene and repeat element sequence (RE). For strain typing purpose, the genetic marker of SAG2 was used in nested-PCR. To perform RFLP procedure, the products of nested-PCR were digested using Sau3aI and HhaI enzymes. Results A total 486 stool samples were examined to the amplification of the 194 bp fragment of B1 gene that 35 samples (7.2%) were positive. All positive samples were confirmed by using another PCR that was amplified the 130 bp repeat element sequence (RE). The identified genotypes were type III (32 cases), mix of type I and III (2 cases) and one of the samples was type I. Conclusion Our findings revealed a relatively high prevalence of T. gondii oocysts in stool samples obtained from cats. It is essential that the high-risk people receive the information about the risk of direct and indirect contact with the animals.

Soil Contamination With Eggs of Toxocara Species in Public Parks of Karaj, Iran

Background: Human toxocariasis is one of the zoonotic helminth diseases that is usually occurred with exposure to contaminated soil. Both Toxocara canis and Toxocara cati are considered the causative agents of Toxocara infection. Objectives: This survey was intended to provide data on the Toxocara species eggs contamination in soil samples in the public parks of Karaj, Iran. Materials and Methods: This study was carried out among 200 soil samples collected from 12 public parks between August and September 2016 to examine the soil contamination with Toxocara species eggs. Soil samples were tested for the presence of Toxocara eggs using sucrose flotation method. Results: Prevalence of Toxocara species eggs in soil samples collected from public parks was 36.4%. The highest number of eggs recovered from 200 g of soil was 20. A total of 200 eggs were recovered and 7.6% were fully developed to embryonated egg stages. The contamination rate in the third region in 4 studied areas was higher than the other regions. A similar tendency was observed in park areas, so that parks higher than 5000 m2 were highly contaminated. Conclusion: According to the results of this study, soils of the public parks in Karaj are one of the main risk factors for human toxocariasis.

Profile of Geohelminth Eggs, Cysts, and Oocysts of Protozoans Contaminating the Soils of Ten Primary Schools in Dschang, West Cameroon.

Helminthiasis and protozoans infections have been recognized as an important public health problem. The aim of the present study was to screen soil samples collected from 10 primary schools in the city of Dschang for the presence of soil-transmitted helminth eggs, cysts, and oocysts of protozoans. A total of 400 soil samples were collected around latrines, at playgrounds, and behind classrooms in each school. These samples were examined using the sucrose flotation method. From the result obtained, an overall contamination rate of 7.75% was observed. Five genera of nematodes (Ascaris, Trichuris, Capillaria, Cooperia, and hookworms) were identified, while neither cysts nor oocysts of protozoans were detected. The contamination rate and the number of species found were significantly different in wet season as compared to the dry season. During the rainy season, this rate was 12.5% with all the parasitic stages identified, while, in the dry season, the soil contamination rate was 3% with the presence of only two genera (Ascaris and Trichuris). This suggests that parasite infection may occur mainly in rainy season rather than in the dry season. The most common eggs were those of Ascaris with 2% and 5% contamination rates in the dry and rainy seasons, respectively. Also, the soils around latrines were more contaminated (11.9%) as compared to those collected behind classrooms (7.5%) and those at playground (2.5%). It was concluded that the pupils of these schools may have played a major role in the contamination of their environment. Thus, sanitary education, enforcement of basic rules of hygiene, and deworming remain a necessity in the entire population of the study area in general and in the schools in particular in order to prevent helminth infections and to ensure effective environmental health.

Contamination of Soil Samples of Public Parks with Toxocara spp. Eggs in Kermanshah, Iran

Toxocariasis is a zoonotic helminth infection, occurring in humans by the accidental ingestion of embryonated eggs of Toxocara canis and less frequently Toxocara cati . The present study was conducted to determine the existence of Toxocara spp. eggs by using the sucrose flotation method. A total of 150 soil samples were collected randomly from 7 public parks in Kermanshah city between September and December 2014 for investigating the presence of infective stages of parasites and to determine the prevalence of helminth eggs. Of the 150 soil samples examined, 27 (18%) were infected with eggs of Toxocara spp. eggs. The present investigation showed that humans (especially children) from urban areas are at risk of acquiring helminth infection from contaminated soil. Since this host species is capable of transmitting zoonotic agents to both animals and humans, animal populations, including stray dogs and cats, have to be controlled to minimize the distribution of parasites.

Genotyping of Giardia lamblia and Entamoeba spp from river waters in Iran.

In this study, DNA from 55 surface and river water samples, which were collected from some water sources of Tehran and the Guilan Province, Iran, were extracted and examined for Entamoeba spp. and Giardia lamblia by PCR and genotyping. Twenty-seven samples, which were concentrated using the immunomagnetic separation technology (IMS) method, were examined for Giardia alone. Twenty-eight samples, which were concentrated using the sucrose flotation (SF) method, were examined for both Giardia and Entamoeba species. The results showed that 27/55 (17/27 and 10/28) (49%), 4 /28 (14.28%) and 3/28 (10.7%) of the samples were positive for Giardia lamblia, Entamoeba spp and mixed infections (Entamoeba spp. and Giardia spp.), respectively. Sixteen out of 55 samples were negative. Entamoeba genus-specific PCR primers in single-round PCR were used to differentiate between the Entamoeba spp. (E. histolytica, E. dispar and E. moshkovskii). With respect to the 7 samples that were positive for Entamoeba, (14.28%) 4 out of 28 were positive for E. moshkovskii, (7.14%), 2 out of 28 were positive for E. histolytica and (3.57%) 1 out of 28 was positive for E. dispar. Genus-specific PCR primers in a semi-nested PCR assay was performed to genotype Giardia species. Of the 27 samples that were positive for Giardia, 10 samples were sequences. All 10 successfully sequenced samples contained assemblage B of Giardia lamblia.This is first study to investigate the G. lamblia genotypes in the water supply of the Tehran and Guilan provinces, and it is the first study to investigate Entamoeba species in the water supplies of Iran. The investigated river water supplies, which are used for agriculture, camping and animal farming, were heavily contaminated by the human pathogenic Entamoeba and Giardia parasites. There is a potential risk of waterborne outbreaks in humans and animals.

PCR-Based Molecular Characterization of Toxocara spp. Using Feces of Stray Cats: A Study from Southwest Iran

Feces of stray cat are potential sources of gastrointestinal parasites and play a crucial role in spreading and transmitting parasite eggs, larvae, and oocysts through contamination of soil, food, or water. In this study, we investigated the prevalence of Toxocara spp. infection in stray cats in Ahvaz city, southwest Iran. Eggs of Toxocara spp. in feces of stray cats were detected by the sucrose flotation method, and identification was conducted by polymerase chain reaction (PCR) and DNA sequencing. Of the 140 fecal samples that were randomly collected from public environments during the months of January to May 2012, 45% were found to harbour Toxocara spp. eggs. The highest prevalence of Toxocara spp. eggs was found in the central area of Ahvaz city (28.6%). T. canis eggs were found in 4 (6.34%) of the 63 positive samples. Stray cats are found in parks, playgrounds, and other public places and may be a potential contamination risk. Identification of Toxocara spp. using molecular methods is sufficiently sensitive to detect low levels of parasites and identify the different Toxocara spp. in feces. The relatively high prevalence of Toxocara spp. infection may continue to increase due to lack of effective environmental hygiene control in Iran. Consequently, there is a need to plan adequate programs to detect, identify, and control this infection as well as stray cats in the region.

Cryptosporidium species detected in calves and cattle in Dagoretti, Nairobi, Kenya

A total of 1,734 cattle faecal samples from 296 dairy-keeping households were collected from urban settings in Nairobi, Kenya. Modified Ziehl-Neelsen staining method and an immunofluorescence assay were used to identify those samples with Cryptosporidium oocyst infection. Oocysts from positive faecal samples were isolated by Sheather's sucrose flotation method and picked from the concentrate using cover slips. Genomic DNA was extracted from 124 of the faecal samples that were positive for Cryptosporidium and was used as template for nested PCR of the 18S rRNA gene. Twenty-five samples (20 %) were PCR-positive for Cryptosporidium, and 24 of the PCR products were successfully cloned and sequenced. Sequence and phylogenetic analysis identified 17 samples (68 %) as Cryptosporidium parvum-like, four samples (16 %) as Cryptosporidium ryanae, three samples (12 %) as Cryptosporidium andersoni and one sample (4 %) as Cryptosporidium hominis. To the best of our knowledge, this is the first genotyping study to report C. parvum-like, C. andersoni and C. hominis in cattle from Kenya. The results of this study show Cryptosporidium infections in calves and cattle may be potential zoonotic reservoirs of the parasite that infects humans.

Prevalence of parasites in soil samples in Tehran public places

The aim of this study was to determine the prevalence of all parasitic forms (eggs, larvae, cysts and oocyst) by using two flotation methods in soil of public places and children’s playgrounds in Tehran City, Capital of Iran. During 2008 to 2009, 150 soil samples were collected from various sites by simple random selection. To recover parasites, the soil samples were examined by sodium nitrate flotation, sucrose flotation method. The McNemar test and Kappa Index were used to analyse the statistical significance of the results. The prevalence of soil parasites was as follows:Toxocara spp. eggs in sodium nitrate flotation (38.7%) and in sucrose flotation method (33%), Isospora spp. in sodium nitrate flotation (10.7%) and in sucrose flotation method (18.7%), nematode larvae in sodium nitrate flotation (40.7%) and in sucrose flotation method (24%), Eimeria spp. in sodium nitrate flotation (8.7%) and in sucrose flotation method (24.7%), Coccidian oocyst and Sarcocystis spp. in sodium nitrate flotation (27%) and in sucrose flotation method (42%), Dicrocoelium dendriticum in sodium nitrate flotation (2.7%) and in sucrose flotation method (2%), Geohelminths in sodium nitrate flotation (6.7%) and in sucrose flotation method (3.4%). Furthermore, following sucrose flotation method performance, modified Ziehl-Neelsen staining technique was done and oocysts of Cryptosporidium spp. was detected in 15 (10%) of soil samples. According to McNemar test, the sodium nitrate flotation and sucrose flotation method statistically were differed to parasites detection. Results of our findings provide evidence that soil may play an important role in transmission of zoonotic parasite diseases to human. In addition, control of high population of animals such as stray dogs and cats is necessary to reduce the distribution of parasites. Key words: Prevalence, parasites, flotation method, Tehran.