Investigating the Invasive Contamination of Lymnaeidae Snails with Trematodes According to Species and Sampling Location in Lorestan province, Iran, Middle East.

Eosinophilic meningitis risk associated with raw Ampullarium canaliculatus snails consumption

A study on the snail species composition and their cercariae was conducted in 8 sixth-level canals across three inland districts of the Ho Chi Minh City area, namely Cu Chi, Hoc Mon and Binh Chanh. The time of study was in January 2022 (the dry season) and July 2022 (the wet season). A total of 584 snail samples, representing 12 species from 12 genera and 7 families, were collected, and identified using morphological methods, with Melanoides tuberculata being the most dominant species. The total number of snail species observed during the rainy season (12 species) was higher than during the dry season (11 species). Four snail species were found to be infected with Xiphidio cercariae: Bithynia siamensis, Filopaludina sumatrensis, Sinotaia lithophaga, and Melanoides tuberculata while Indoplanorbis exustus was infected with Echinostome cercariae. The prevalence of trematode infection in snails was higher in the wet season compared to the dry season (P<0.05). The other seven snail species were free of cercariae. The findings provide valuable information about the diversity of snails in canals of the inland districts of Ho Chi Minh City. Further research on snails and cercariae in canals that supply water directly to fishponds and rice fields is recommended to support sustainably agricultural development.

Relationships between labor migration and cropland abandonment in rural China from the perspective of village types

Diversity of digenean trematode larvae in snails from Lake Victoria, Kenya: First reports and bioindicative aspects

Bithyniids are freshwater snails that play a crucial role in the transmission of various parasitic trematodes of medical and veterinary importance. In this study, we explored the prevalence of cercarial trematode infections in bithyniid snails from Thailand and examined the species diversity of both the intermediate snail hosts and parasite larvae. A total of 688 bithyniid snails were collected from diverse natural habitats at 24 locations in 16 provinces across 5 regions of Thailand. The presence of larval trematode infections was examined using the cercarial shedding method. Both the collected snails and the emerging cercariae were identified at the species level using a combination of morphological and molecular techniques. The mitochondrial COI and 16S rDNA sequences of bithyniid snails, along with the ITS2 sequences of cercariae, were obtained via PCR amplification and sequencing. Three species of bithyniid snails were identified in this study: Bithynia funiculata, Bithynia siamensis siamensis, and Hydrobioides nassa. Among these species, B. s. siamensis exhibited the highest population density, followed by B. funiculata and H. nassa. The overall rate of cercarial infection in the bithyniid snails was relatively low, at 1.45%. H. nassa snails had the highest infection prevalence, at 11.11%, while B. s. siamensis had a prevalence of 1.39%. Only the morphological type of the xiphidiocercariae was detected. BLASTn searches in GenBank and phylogenetic trees based on xiphidiocercariae were used to classify the samples into four different families spanning two superfamilies of digenean trematodes. The genera Plagiorchis, Prosthogonimus, Paralecithodendrium, and cercaria of Renicolidae are reported for the first time in B. s. siamensis. Plagiorchis and Paralecithodendrium are significant genera of zoonotic trematodes. These findings indicate that B. s. siamensis and H. nassa can act as the first intermediate hosts for various parasitic trematodes in Thailand.

When compared with the plains villages, the construction and development of traditional mountain villages always in relatively slow due to the impact of the geographical remoteness, inaccessibility and other factors. However, the beautiful natural environment and rich flavor of the countryside exudes a different kind of vitality in nowadays "urbanization" process. In this paper, take a typical representative of mountain villages in Yimeng Shilin tourism area -- Nanyu village as example, based on the analysis of its natural scenery and cultural history, we focus on the spatial characteristics of the mountain village to explore the changes and development in the rural tourism development process. 1.Mountain village 1.1 The concept of mountain village A village is a collection of many residential houses or a population concentrated area. According to its geographical location, it can be divided into different type of villages such as plains village, mountain village, prairie village, lakeside village, coastal village, delta village. Mountain village, as the name implies, is located between the mountains and hills or species distribution along the direction of the river or valley. 1.2 The current situation of mountain village in tourism area When compared with the reinforced concrete modern city, mountain villages have a great environment like near the river or lush vegetation. Thus, mountain villages attract more and more tourist because of its rustic and natural can let people feel spirit release. Meantime, it add new vigor and vitality to the past quiet mountain village. However, the inconvenience of traffic and the backward of public service facilities such as health and dining, which will undoubtedly become a "stumbling block" hinder the development of mountain villages. Throughout the tourist area around the mountain villages, the majority are more like a single industrial structure, relatively monotonous series of products, and the lack of a distinctive characteristic or humanistic values, and therefore cannot be formed as the "attractions" which have the attractive "center of interest". As a result, it often act as a "supporting role" in the tourism development process like a auxiliary facilities or "service area", which also reduce the original intention to promote the economic development of those areas.

Physical and chemical properties of alkali-treated agar polymers extracted from Gracilariopsis lemaneiformis, newly reported Japanese agarophyte, were investigated after partial acid hydrolysis. The alkali-treated agar was hydrolyzed in boiling 0.1 N, 0.01 N, and 0.001 N sulfuric acid, oxalic acid, acetic acid, and citric acid solutions, for 1, 2, and 3 h at 100 °C. Partial acid hydrolysis of the agar polymers indicated strong effects on the physical properties. Different kinds of acid used for hydrolysis gave different agar properties. Gelling polymers were obtained from the agar hydrolysed in boiling 0.001 N acetic acid, oxalic acid, and citric acid solutions, and in 0.01 N acetic acid solution. High gel strength (715 ± 74.6 g cm-2) with low viscosity (2.47 cP) was obtained from 1 h treatment by 0.001 N acetic acid on hydrolysed agar. The results indicated that partial hydrolysis of agar under appropriate conditions probably improve agar quality and produce good grade agar from the Japanese agarophyte.

Fasciolosis is a food-borne disease that causes major economic losses, globally. This zoonotic disease is caused by Fasciola hepatica and Fasciola gigantica species which employ freshwater snails from the family Lymnaeidae as their intermediate hosts. Thus, a key aspect of understanding the epidemiology of the disease lies in understanding the transmission ecology of the parasite. Therefore, this systematic review and meta-analysis were conducted to assess the experimental susceptibility and prevalence of natural infections of F. hepatica and F. gigantica in lymnaeid snails. Relevant peer-reviewed articles published in the past 20 years (2004-2023) were searched and appraised. Prevalence and infection rate estimates were based on 41 studies that met the inclusion criteria. Five thousand five hundred and seventy-five (5,575) lymnaeid snails were subjected to experimental infections and 44,002 were screened for natural infections. The overall pooled infection rate was higher in experimental infections 50% (95% CI [42-58%]) compared to natural infections of field-collected snails 6% (95% CI [0-22%]). The highest pooled infection rate was recorded in South America at 64% (95% CI [48-78%]) for experimental infections while the lowest was recorded for natural infections at 2% (95% CI [0-6%]) in Europe and 2% (95% CI [0-17%]) in Asia. In experimental studies, F. gigantica recorded the highest pooled prevalence at 73% (95% CI [61-84%] compared to F. hepatica which recorded 47% (95% CI [38-56%]). For natural infections, however, F. hepatica had the highest prevalence (12% (95% CI [0-30%]) while the lowest was noted for naturally infected F. gigantica at 2% (95% CI [0-18%]). Based on the snail species, the highest pooled prevalence was recorded for Pseudosuccinea columella infected with F. hepatica and F. gigantica at 47% (95% CI [33-61%]) while the lowest was recorded for F. hepatica naturally infected Galba truncatula at 4% (95% CI [0-10%]). Natural Fasciola spp. infections in intermediate snail hosts decreased in prevalence while experimental infections have increased in prevalence over the past 20 years. While there seems to be a strong intermediate host specificity between the two Fasciola spp., experimental infection results showed that G. truncatula and R. natalensis are susceptible to F. hepatica and F. gigantica, respectively.

A study was conducted to assess the infectivity and transmission potential of freshwater snail intermediate hosts at Lake Njoboliyo, Adamawa State, Nigeria. Snail samples were collected monthly from November 2023 to March 2024 using a scoop net with a 2 cm mesh size, supplemented by handpicking. In total, 1,602 freshwater snails were collected and identified to species level based on their morphological characteristics using standard identification keys. The snail species observed were: Melanoides tuberculata (490, 30.6%), Bellamya unicolor (387, 24.2%), Pila ovata (328, 20.5%), Lanistes ovum (288, 17.9%), Lymnaea natalensis (74, 4.6%), Bulinus globosus (19, 1.2%), Cleopatra bulimoides(10, 0.6%), and Bulinus truncatus(6, 0.4%). The snails were screened for natural infections by exposing them individually to sunlight for two hours in pre-labeled shedding vials containing 10 mL of filtered water from their collection site. The results showed that Lanistes ovum and Pila ovata were the only snail species naturally infected, though, of non-human schistosomes. No cercariae were shed by Bulinus globosus, B. truncatus, Lymnaea natalensis, or other species. There was no significant difference in infection rates between the infected snails (p > 0.05). The overall infection rate at Lake Njoboliyo was 2.75%, with Lanistes ovum and Pila ovata showing infection rates of 10.70% and 3.96%, respectively. The highest infection rate was observed in December, at 3.87%, coinciding with the highest transmission potential of 32.91%. No significant difference in infection rates was found across the sampling months (p > 0.05). However, Bulinus species showed 0.00% infection and transmission potential, as did other snail species. These findings highlight the importance of implementing targeted interventions during specific months to control snail-borne diseases at Lake Njoboliyo. An effective snail control program and public awareness efforts about the role of snails in disease transmission are strongly recommended.

BackgroundSnail-borne trematodes afflict humans, livestock, and wildlife. Recognizing their zoonotic potential and possible hybridization, a One Health approach is essential for effective control. Given the dearth of knowledge on African trematodes, this study aimed to map snail and trematode diversity, focusing on (i) characterizing gastropod snail species and their trematode parasites, (ii) determining infection rates of snail species as intermediate hosts for medically, veterinary, and ecologically significant trematodes, and (iii) comparing their diversity across endemic regions.MethodsA cross-sectional study conducted in 2021 in Chiredzi and Wedza districts in Zimbabwe, known for high human schistosomiasis prevalence, involved malacological surveys at 56 sites. Trematode infections in snails were detected through shedding experiments and multiplex rapid diagnostic polymerase chain reactions (RD-PCRs). Morphological and molecular analyses were employed to identify snail and trematode species.ResultsAmong 3209 collected snail specimens, 11 species were identified, including schistosome and fasciolid competent snail species. We report for the first time the invasive exotic snail Tarebia granifera in Zimbabwe, which was highly abundant, mainly in Chiredzi, occurring at 29 out of 35 sites. Shedding experiments on 1303 snails revealed a 2.24% infection rate, with 15 trematode species identified through molecular genotyping. Five species were exclusive to Chiredzi: Bolbophorus sp., Schistosoma mansoni, Schistosoma mattheei, Calicophoron sp., and Uvulifer sp. Eight were exclusive to Wedza, including Trichobilharzia sp., Stephanoprora amurensis, Spirorchid sp., and Echinostoma sp. as well as an unidentified species of the Plagiorchioidea superfamily. One species, Tylodelphys mashonensis, was common to both regions. The RD-PCR screening of 976 non-shedding snails indicated a 35.7% trematode infection rate, including the presence of schistosomes (1.1%) Fasciola nyanzae (0.6%). In Chiredzi, Radix natalensis had the highest trematode infection prevalence (33.3%), while in Wedza, R. natalensis (55.4%) and Bulinus tropicus (53.2%) had the highest infection prevalence.ConclusionsOur xenomonitoring approach unveiled 15 trematode species, including nine new records in Zimbabwe. Schistosoma mansoni persists in the study region despite six mass deworming rounds. The high snail and parasite diversity, including the presence of exotic snail species that can impact endemic species and biomedically important trematodes, underscores the need for increased monitoring.Graphical

Ovia South-West Local Government Area of Edo State in Nigeria is endemic for urogenital schistosomiasis. However, there are no reports of snail hosts of the disease in any community within the locality. Ayear-long freshwater snail survey was conducted in seven localities (Aden, Igbogor, Ikoha, Okopon, Okponha, Siluko, and Ugbogui) in Ovia South-West to determine the snail diversity and identify species that are intermediate hosts for schistosomiasis. A total of 468 snails representing species in four genera (Bulinus, Lanistes, Melanoides, and Radix) were collected. Based on the morphological appearances of shells, five snails, B. forskalii, B. globosus, B. truncatus, L. varicus, and M. tuberculata were identified at the species level. The snail Radix could not be identified at the species level. Melanoides tuberculata was the most abundant snail, and the only species identified at all sampled locations (n = 284, 60.68%). The next most abundant species was Radix sp. (n = 106, 22.65%), followed by B. globosus(n = 42, 8.97%). The least abundant snail was B. truncatus (n = 5, 1.07%). In Siluko, all species of snails were present, and only M. tuberculata was present in Ugbogui. In both the dry and wet seasons, all snail species were present (wet, n = 297) (dry, n = 171). Similar snail diversity occurred at each sampling location in both seasons, with more individuals of each species collected during the wet season. The only infected snail was a single Radix sp. in Siluko that shed the brevifurcate-apharyngeate distome furcocercariae. All the other snail species were uninfected.

The effects of different organic acid solutions on enzymatic browning of “Baby” lettuce and “Geante Maraichiere” endive were assayed by quantitative measurement of colour changes. Acetic, formic, propionic, malonic, oxalic and lactic acid solutions (10 g l–1) were the most effective at preventing discoloration in stem discs taken from the vegetables. Among the above treatments, acetic, propionic, malonic and oxalic acid solutions (50 g l–1) were selected and applied with the help of cotton wool to the butt end of lettuce and endive heads. The browning process was evaluated during 7 days of storage at 2°C, plus an additional commercial handling period of 2 days at 13°C. Acetic and propionic acid treatments were the most effective at reducing lettuce-butt discoloration during storage and commercial handling. In general, treatments with organic acid solutions were less effective on endive than on lettuce.

Performance improvement of direct methanol fuel cells (DMFCs) was achieved via an anodic treatment technique. Previously, anodic treatment was performed using sulfuric acid as acidic media, but various organic acids including formic, acetic, oxalic, and citric acids were employed in this study to avoid the use of toxic sulfuric acid. By replacing sulfuric acid to organic acids, a potential damage to catalyst layers and other components such as polymer electrolyte membrane and bipolar plates are expected to be minimized. The anodic treatment was performed by applying 0.7 V (vs. reversible hydrogen electrode) at the anode of DMFCs flowing the organic acid solutions for 30min. After the anodic treatment, peak power densities of DMFCs were increased by +7, +32, +23, and −2.6% when formic, acetic, oxalic, and citric acid solutions were employed, respectively. The enhanced catalytic activity of the DMFCs in the acetic and oxalic acid solutions was confirmed by analyzing electrochemical impedance spectroscopy data.

Introduction: Freshwater snails, particularly snails from the genus Biomphalaria, play a key role in the transmission of schistosomiasis, a parasitic disease prevalent in tropical regions. Schistosomiasis poses a significant public health challenge in these regions, leading to chronic illness, reduced productivity, and impaired childhood development, particularly in communities with limited access to healthcare and sanitation. Understanding the seasonal and spatial variations in snail populations and infection rates is crucial for controlling schistosomiasis, especially in areas like Southwest Ethiopia, where the disease burden is high. Methods: This study was conducted in Mizan Aman, Southwest Ethiopia, across two seasons, dry and wet. A total of 1150 snail samples were collected from 20 freshwater sites, and their species, abundance, and infection status were assessed. Environmental parameters, including temperature, pH, salinity, and conductivity, were measured to analyze their impact on snail populations. Results: Four snail species were identified, Biomphalaria pfeifferi, Biomphalaria sudanica, Lymnaea natalensis, and Bulinus globosus, with B. pfeifferi and B. sudanica being the most prevalent. Snail abundance varied by site and season, with 598 in the dry season and 552 in the wet season. Snail abundance and species composition showed significant spatial variation, with higher counts in sites like Sasin and Agu 1, while some sites had no snails. Biomphalaria snails, particularly B. pfeifferi, are the principal intermediate host for Schistosoma mansoni. The overall prevalence of Biomphalaria snails exceeded 85% in both seasons, and their average infection rate in Mizan Aman was 13.5%. This infection rate showed a strong correlation (r = 0.733, p < 0.001) with the incidence of schistosomiasis cases in the community. Seasonal variation in environmental factors, such as temperature and pH, had no significant effect on snail abundance; however, water salinity showed to be correlated with snail abundance during the dry season. Furthermore, community-led vegetation clearance at selected sites significantly reduced snail abundance. Conclusions: This study highlights the seasonal and spatial dynamics of freshwater snails, particularly Biomphalaria species, in relation to schistosomiasis transmission in Mizan Aman, Southwest Ethiopia. The findings confirm that B. pfeifferi species is the predominant intermediate host for schistosoma in this region and that schistosomiasis infection rates among snails significantly correlate with human cases in the community. While environmental factors such as temperature and pH showed no significant influence on snail abundance, water salinity had an impact during the dry season. Additionally, community-led vegetation clearance was an effective intervention in reducing snail populations. These results emphasize the need for targeted, site-specific control measures integrating ecological and community-based interventions to sustainably reduce schistosomiasis transmission.

This study was conducted to identify the potential of rape stalk as a raw material for biorefinery process of rape flower. At first, rape stalk (RS) was immersed in distilled water (DW), acetic acid (AA), oxalic acid (OA), sulfuric acid (SA) and sodium hydroxide (SH) solutions, and the content of reducing sugars liberated from immersed RS was analyzed. Glucose, xylose, arabinose and sucrose were detected varying with the immersion type. In particular, 1% AA-immersion of RS for 72 hr was the most effective conditions to liberate glucose from RS. Secondly, the RS residues were used for elementary analysis and fabrication of fuel pellets. In addition to the solution type, concentration of immersion solutions (0%, 1%, 2%) and immersion time (24, 72, 120 hr) were used as experimental factors. The contents of nitrogen, sulfur and chlorine reduced effectively through the immersion of RS in DW, AA and OA solutions. For properties of RS-based pellets, bulk density and higher heating value of RS-based pellets greatly increased with the immersion of RS, and the qualities were much higher than those of the A-grade pellet of the EN standards. Ash content decreased remarkably through the immersion of RS, and was satisfied with the A-grade pellet standard. Durability was negatively affected by the immersion of RS, and did not reached to B-grade of the EN standard. In conclusion, acid immersion of RS can be a pretreatment method for the production of fuel pellet and bioethanol, but use of the immersed RS for the production of high-quality pellets might be restricted due to low durability of immersed-RS pellets. Therefore, further studies, such as investigation of detailed immersion conditions, fabrication of mixed pellets with wooden materials and addition of binders, are needed to resolve the problems.