Search Results (56)

Enterobacter spp. and Giardia duodenalis are two resistant and globally distributed pathogens widely reported in humans and animals worldwide. To contrast the antimicrobial resistance phenomenon, this study aimed to evaluate the in vitro activity of antimicrobial peptides (AMPs), such as temporins, on the viability of Enterobacter spp. and G. duodenalis cysts isolated from naturally infected dogs. A total of 50 clinically healthy dogs were sampled, with 25 in each of the two sampling sessions. Rectal and oral swabs for Enterobacter spp. and fecal samples for G. duodenalis isolation were carried out. The AMPs were synthesized by a solid-phase peptide synthesis approach. Enterobacter ludwigii and E. hormaechei strains were isolated from two different dogs, while 16 dogs were positive for G. duodenalis. Subsequently, cysts and bacterial strains were treated with the following peptides: TL-34, TL-48, TL-42, TL-51, RB-71, and RB-58 at different concentrations (i.e., 250 mg/mL, 125 mg/mL, 62. mg/mL, and 31.25 for Enterobacter spp. strains and 0.15 mg/mL, 0.3 mg/mL, 0.6 mg/mL, and 1.2 mg/mL for G. duodenalis cysts). The results showed antimicrobial activity of TL-34, TL-48, and RB-71 against the two Enterobacter strains, while TL-51/TL-42 and RB-58 were not effective. In contrast, for G. duodenalis, TL-34, TL-48, TL-42, and RB-58 were effective at the two highest concentrations, inhibiting the viability of 100% of Giardia cysts, while the other two peptides (TL-51 and RB-71) showed less effectiveness. The AMPs used in this study have in vitro antimicrobial activity on cysts and bacterial strains and appear to have potential for the treatment of these infections in dogs. Full article

Thalassogenic diseases are human infections associated with exposure to marine environments. This review explores the occurrence of Cryptosporidium spp., Giardia duodenalis, and Blastocystis sp. in seawater and shellfish and their implications for public health. Between 2015 and 2026, multiple studies reported the presence of these parasites in shellfish and seawater. Cryptosporidium spp. was found at average concentrations of 5.5 × 10¹ oocysts/g in shellfish and up to 3.7 × 10¹ oocysts/L in seawater. Giardia duodenalis reached 9.1 × 10¹ cysts/g in shellfish, close to the infectious dose, and 3.5 × 10¹ cysts/L in seawater. Blastocystis sp. showed prevalence rates of 33.82% in shellfish and 17.3% in seawater. These findings highlight a potential infection risk for bathers and seafood consumers, emphasizing the need to determine the specific species (or subtypes) involved and assess their viability to accurately evaluate public health implications. The persistence of these parasites in the environment needs improved monitoring. Future strategies should integrate next-generation sequencing (NGS) or use of various fecal indicators to enhance environmental surveillance and reduce health risks in coastal regions. Full article

Rumen development is critical for optimal growth, feed efficiency and health in pre-weaned dairy calves. Butyric acid, a short-chain fatty acid produced in the rumen, has been shown to stimulate epithelial development and modulate immune responses. This study evaluated the effects of butyric salt supplementations, as metabiotics, on rumen morphometry and investigated the potential associations with feed intake, growth performance and health indicators in pre-weaned dairy calves. Thirty calves were randomized into three groups: controls (G1), 25 g (G2) or 50 g (G3) sodium butyrate from birth until weaning. The gross and histological rumen morphometry, dry matter intake, growth performance, complete blood count, total protein determination and fecal (oo)cyst counts for Giardia spp. and Eimeria spp. were analyzed using one-way ANOVA. When significant effects were detected, treatment means were compared using Tukey’s HSD at p ≤ 0.05. Sodium butyrate supplementation produced dose-dependent responses. Compared with controls (p ≤ 0.05), G3 calves had a greater mean papillae height (3.20 vs. 1.36 mm) and rumen wall thickness (7.08 vs. 3.62 mm), higher final body weight (93.9 vs. 80.1 kg), increased daily weight gain (798 vs. 550 g/day), increased total dry matter intake (69.4 vs. 55.1 kg) and improved feed conversion ratio (1.45 vs. 1.67). In addition, G3 calves showed reduced Giardia and Eimeria (oo)cyst excretions and favorable hematological shifts at weaning (i.e., higher hematocrit, hemoglobin and mean corpuscular hemoglobin concentration and altered leukocyte differentials) consistent with improved health. In conclusion, sodium butyrate supplementation in pre-weaned dairy calves resulted in dose-dependent improvements in rumen morphometry, voluntary dry matter intake and growth performance. These physiological benefits were accompanied by decreased Giardia spp. and Eimeria spp. (oo)cyst shedding and by positive shifts in hematological health indicators, suggesting a potential enhancement of the animals’ immune response. Full article

Background: The cysts of the protozoan parasite Giardia duodenalis, which targets a broad spectrum of hosts including humans, can withstand environmental conditions for months, making effective disinfectant measures crucial for minimizing the infection burden. Previous investigations concerning disinfection efficacy were based on cysts from fecal/water samples or animal models, which are either unfit for standardized procedures or related to ethical concerns. Methods: To perform standardized in vitro disinfectant testing, four different encystation protocols were compared firstly. The protocol with the highest efficacy in our hands (1.7 × 10⁵ cysts per tube) was used for the production of cysts to establish a disinfectant assay. Therefore, it was used for the production of cysts to establish a dis-infectant efficacy assay. After incubation with a commercial disinfectant (ViPiBaX Giardien Ex^®) or 30% hydrogen peroxide solution (H₂O₂) at 10 °C and room temperature, parasite cyst viability was evaluated by the yield of trophozoites obtained by the applied excystation protocol. Results: Only untreated Giardia cysts, which were used as a negative con-trol, released trophozoites. The protocol established for the evaluation of cyst viability delivered reproducible results and appeared suitable for testing the inactivation of cysts by chemical disinfection. Conclusions: Under the given conditions, the disinfectant ViPiBaX Giardien Ex^® and H₂O₂ inactivated Giardia cysts. Full article

Neonatal calf diarrhoea (NCD) is the leading cause of mortality in calves under 30 days old. Although several pathogens are usually involved in outbreaks, most previous research has focused on specific enteropathogens or on the four agents traditionally associated with this syndrome. This study aimed to determine the prevalence of thirteen enteropathogens in 420 diarrhoeic calves under a month of age from north-western Spain and to identify the most frequent co-occurrences. Four diarrhoeagenic pathotypes of Escherichia coli, bovine rotavirus A, coronavirus, norovirus, nebovirus and torovirus were identified using qPCR. Presence of Salmonella spp. was studied using a serum agglutination test. A direct immunofluorescence assay was employed to identify Cryptosporidium and Giardia duodenalis oo/cysts. Eimeria oocysts were found by the floatation technique. Our results confirm the co-occurrence of agents in most cases of NCD. A total of 172 pathogen combinations, involving up to seven agents, were identified. Cases involving one or more viral agents and Cryptosporidium parvum were predominant, maybe because viral immunosuppression facilitates the protozoan life-cycle. The frequent detection of agents typically overlooked in the aetiological diagnosis of NCD suggests that they may play a role in this syndrome and thus should be included in routine diagnostic panels, allowing implementing the most effective control measures. Full article

Access to clean and safe drinking water is crucial for global health and well-being, formally recognised as a fundamental human right within the United Nations’ Sustainable Development Goals. However, the integrity of water supply is increasingly threatened by microbial contamination, a risk aggravated by the conditions driven from climate change, which promotes the proliferation, resilience, and facilitation of the dissemination of microorganisms. Pathogens like Legionella, Cryptosporidium, Giardia, Escherichia coli, and Vibrio cholerae can be present in water supplies, developing survival strategies (e.g., biofilm, cysts, inside protozoa). The risk of microorganisms in water requires both effective treatment at drinking water treatment plants and vigilant process control throughout drinking water distribution systems. Globally, a great number of disease outbreaks have been linked to contaminated drinking water. Despite strong regulations in the European Union and the Drinking Water Directive aim to guarantee the safety and quality of potable water, outbreaks persist; recent Legionella cases in Italy in 2024 and Cryptosporidiosis in 2019 linked to rainfalls and insufficient disinfection treatment, respectively, are an example of this. Although cholera is not common in Europe, there is evidence of high incidence of this disease in Africa mainly due to the poor hygienic conditions in the DWTS. In Europe, the data of waterborne diseases and outbreaks are submitted by European Countries to the European Centre for Disease Prevention and Control (ECDC) to give faster and effective response to outbreaks. Determining the origin of the contamination is essential to face the solution of outbreaks and ensure public health safety. Full article

Giardiasis is a globally prevalent waterborne zoonosis. Rapid enrichment and detection technologies for this disease are essential. Cyst outer wall proteins are ideal targets for the enrichment and detection of cysts in the environment, but there are few available targets with suboptimal effectiveness. In this study, Giardia duodenalis (G. duodenalis) cysts were purified, and outer wall proteins were biotinylated, followed by streptavidin magnetic bead purification and mass spectrometry. Sixty-three novel cyst wall proteins were identified, and their functions were annotated through Gene Ontology (GO) and KEGG analyses. The β-giardin and α-1 giardin were among the newly identified and predicted to be located on the outer wall of G. duodenalis cysts. For the characterization of these two targets, we applied sequence analysis, prokaryotic expression, preparation of polyclonal antibodies, and determination of subcellular localization. Finally, based on β-giardin immunomagnetic beads were prepared using the polyclonal antibodies and tested for their enrichment efficiency. Immunomagnetic beads targeting β-giardin achieved 65% cyst enrichment efficiency in fecal samples, comparable to conventional methods. Clinical evaluation across 163 multi-host fecal samples (ferrets, Siberian tigers, red-crowned cranes) demonstrated concordance with nested PCR, successfully enriching cysts from PCR-positive specimens. The immunomagnetic beads method targeting β-giardin demonstrated effective G. duodenalis cyst enrichment in multi-host fecal samples. These results provide a proteomic framework for the cyst wall proteins of G. duodenalis, expanding the detection targets for G. duodenalis cysts. It also establishes a theoretical foundation for subsequent research on the composition and function of G. duodenalis cysts. Full article

Background/Objectives: Giardiasis is one of the oldest-reported infectious diseases worldwide. It affects individuals with weakened immune systems and progresses into chronic infection if untreated. Morphological analysis and visualization of cell shapes using unlabeled or fluorophore-labeled samples are commonly employed to identify the parasite. Methods: To distinguish molecular content variations between trophozoites and infectious type I cysts, the current research presents an alternative approach based on label-free Raman microscopy. Results: Constituents responsible for plasma membrane thickening and cyst wall formation during encystation, such as N-acetylgalactosamine (GalNAc) and N-acetylglucosamine (GlcNAc) were detected. Although these two coexisting compounds have similar molecular structures, their spectroscopic distinction and visual localization through Raman microscopy are achievable. While immature and non-viable cysts contain a larger amount of GlcNAc, a potential transition of this moiety to GalNAc might occur as the cysts mature and become infectious. Other Raman results revealed changes in the oxidation states of heme-binding proteins and in lipid–protein metabolism, each serving as an additional protection mechanism that the parasite employs for survival. Complementary bright field and confocal fluorescence microscopy results corroborate the Raman outcomes. Conclusions: The molecular-level findings of this work, which presents a detailed spectroscopic analysis of Giardia’s encystation and excystation stages, substantiate the need to use complementary methods for monitoring the parasite’s dynamics and efficacy in terms of self-protection. This alternative method provides accurate insights for further understanding the multifaceted factors involved in Giardia’s encystation process and its acquired resistance to external stimuli. Full article

The risk of zoonotic parasitic infections is closely linked to direct and indirect interactions between animals and humans. The mutual coexistence of species in public spaces predisposes individuals to gastrointestinal parasitosis owing to various social and hygienic-sanitary factors. This study aimed to assess the risk of environmental contamination by gastrointestinal parasites in fecal samples collected from parks and public squares in 18 municipalities located in a microregion of the central plateau of Brazil, correlating the collection with the population size of each municipality. We collected 536 soil fecal samples from 117 randomly selected public areas across a 56,111.874 km² region. Eggs, cysts, and oocysts were detected using the Willis flotation technique and the Hoffman’s spontaneous sedimentation method. The Hoffman’s analysis revealed that 70.3% of the fecal samples were infected across 91.5% of the sampled areas. Identified parasites included the members of the family Ancylostomatidae (56.5%), Toxocara spp. (6.2%), Trichuris spp. (1.7%), Strongyloides spp. (0.2%), Dipylidium caninum (25.8%), Spirometra spp. (0.4%), Taeniidae (0.2%), Platynosomum fastosum (0.6%), Trematoda (0.2%), Giardia spp. (3.2%), Cystoisospora spp. (5.6%), Sarcocystis spp. (0.2%), and Entamoeba spp. (2.4%). The presence of positive fecal samples in public areas and municipalities correlated with populations of up to 10,000 inhabitants (p = 0.023). Areas contaminated with feces were 63.4% more likely to contain parasites than other areas (odds ratio 1.6336). Favorable environmental factors combined with inadequate sanitary management contribute to a high risk of environmental contamination, representing a significant zoonotic potential and highlighting the need for improved public health policies and preventive measures. Full article

This study investigated the microbiological and parasitic quality of sewage sludge treated in drying beds in Algeria, aiming to contribute to a better understanding of the factors influencing sludge safety for potential agricultural applications in the Algerian context. The research focused on various sludge types (liquid, semi-solid, and solid) and their behavior across different seasons. Standard microbiological methods were employed to quantify total coliforms, fecal streptococci, E. coli, and Clostridium. Controls were implemented to ensure accuracy, with positive controls validating detection methods using known quantities of microorganisms and parasites, while negative controls confirmed the absence of contamination in the testing environment. Parasitic contamination was assessed through microscopic examination for protozoa and helminths. Results revealed substantial variation in microbial concentrations across sludge types and seasons. Liquid sludge, particularly during summer, exhibited the highest levels of total coliforms (up to 7.021 log10) and E. coli (up to 6.049 log10), while solid sludge showed lower counts. Seasonal trends indicated increased microbial levels during warmer months. Parasitic contamination was prevalent in 81% of samples, with protozoan cysts (e.g., Giardia intestinalis and Endolimax nanus) and helminth eggs detected. Despite reducing microbial loads, drying processes alone were insufficient, leaving significant contamination. Enhanced protocols are needed, such as longer drying periods, chemical disinfectants, or advanced technologies like anaerobic digestion or composting. This highlights the need for locally adapted treatment strategies. Furthermore, this research provides specific recommendations for improving sewage sludge management practices in Algeria, taking into account the unique environmental and agricultural context of the country. Full article

Autoimmune pancreatitis type 2 is a relatively novel entity with some still controversial issues. The current diagnostic algorithm relies on imaging studies and histology. Therapy includes corticosteroids with consequently low risk of relapse in the following year. However, the pathogenesis remains unclear, and data are insufficient for long-term prognosis. We have treated a 17-year-old boy whose autoimmune pancreatitis type 2 was revealed during surgery for a pre-existing biliary tract anomaly with concurrent protozoal infection. We discuss the co-occurrence of these conditions in terms of eventual pathogenesis correlation and combined effect on long-term prognosis. Full article

Cryptosporidium and Giardia are infectious parasitic forms widely distributed in aquatic ecosystems and resistant to disinfection of drinking water. Their presence was investigated in the lower areas of the city’s four rivers through a four-stage methodology. Between December 2017 and April 2018, three monitoring campaigns were conducted, with results ranging between not detected to 500 oocysts/L for Cryptosporidium, and between not detected and 300 for Giardia. Cryptosporidium was more abundant, especially in the Machángara River. In the same period, the bacteriological quality of the rivers was also reviewed using Total Streptococci and Fecal Enterococci expressed in colony-forming units (CFU)/100 mL as indicators. The results showed a progressive increase in pollution as the course of the rivers progressed. The sensitivity of bacterial indicators to changes in quality is also observed, which is why their use in specific studies is recommended. It is concluded that untreated domestic wastewater discharges may be the main source of contamination by bacteria and parasites and that there is a relationship between their concentration and the seasonal period. In dry weather, the concentration is higher for both microorganisms. This study fills a gap in knowledge in the region, due to the absence of data on parasitic indicators with great impacts on public health. Full article

Cryptosporidium spp. and Giardia duodenalis are the main non-viral causes of diarrhoea in humans and domestic animals globally. Comparatively, much less information is currently available in free-ranging carnivore species in general and in the endangered Iberian lynx (Lynx pardinus) in particular. Cryptosporidium spp. and G. duodenalis were investigated with molecular (PCR and Sanger sequencing) methods in individual faecal DNA samples of free-ranging and captive Iberian lynxes from the main population nuclei in Spain. Overall, Cryptosporidium spp. and G. duodenalis were detected in 2.4% (6/251) and 27.9% (70/251) of the animals examined, respectively. Positive animals to at least one of them were detected in each of the analysed population nuclei. The analysis of partial ssu rRNA gene sequences revealed the presence of rodent-adapted C. alticolis (n = 1) and C. occultus (n = 1), leporid-adapted C. cuniculus (n = 2), and zoonotic C. parvum (n = 2) within Cryptosporidium, and zoonotic assemblages A (n = 5) and B (n = 3) within G. duodenalis. Subgenotyping analyses allowed for the identification of genotype VaA19 in C. cuniculus (gp60 locus) and sub-assemblages AI and BIII/BIV in G. duodenalis (gdh, bg, and tpi loci). This study represents the first molecular description of Cryptosporidium spp. and G. duodenalis in the Iberian lynx in Spain. The presence of rodent/leporid-adapted Cryptosporidium species in the surveyed animals suggests spurious infections associated to the Iberian lynx’s diet. The Iberian lynx seems a suitable host for zoonotic genetic variants of Cryptosporidium (C. parvum) and G. duodenalis (assemblages A and B), although the potential risk of human transmission is regarded as limited due to light parasite burdens and suspected low excretion of infective (oo)cysts to the environment by infected animals. More research should be conducted to ascertain the true impact of these protozoan parasites in the health status of the endangered Iberian lynx. Full article

Giardia lamblia (G. lamblia) is one of the most common protozoal infections and a key cause of malabsorption, some cases of mental developmental issues in children, and reduced body weight. The known antiparasitic medications, which are the standard drugs used for parasitic treatment, have several side effects and sometimes exhibit low efficacy. Therefore, the current study aimed to evaluate the treatment with quercetin (QC) or chitosan (CH), either alone or in combination, as possible alternative therapeutic agents that may alleviate the side effects of G. lamblia infections and restore the normal architecture of the intestinal muscles. They are investigated as alternatives to other routinely administered drugs that may gradually lose their efficacy due to human resistance to therapeutic agents. This study was carried out on 50 male albino rats that were divided into five groups with 10 rats in each group: the control group (Group I), the infected non-treated group (Group II), the infected group treated with QC (Group III), the infected treated group with CH (Group IV), and the infected group treated with a combination of QC and CH (Group V). The effect was first evaluated by counting the G. lamblia fecal cysts in the stool, examining histopathological sections of the intestine with the appearance of trophozoites in the infected group, and conducting a transmission electron microscopic examination of the tissues of the small intestine. Alterations in the biochemical parameters of liver and kidney function and the antioxidant enzymes in the liver tissues of SOD, CAT, and GSH, and non-enzymatic markers of lipid peroxidation (MDA) were evaluated. The results showed a significant decline in the number of parasites in the stool samples, with a marked elevation in the number of trophozoites in the intestinal sections of the infected non-treated group as compared to the infected treated groups. The last group, which was treated with a combination of QC and CH, showed the best results in terms of a decline in the infection rate of G. lamblia in stool samples, with a marked and clear improvement in the intestinal mucosa, regular muscles with normal enteric ganglions, and reduced rates of intestinal injuries caused by G. lamblia trophozoites. Both QC and CH had non-toxic effects on the biochemical parameters of the liver and kidneys, as well as pronounced antioxidant activities due to the elevation of SOD, CAT, and GSH in conjunction with a decline in the levels of MDA. A combination of QC and CH can be considered a potent antiparasitic, anti-hepatotoxic, and antioxidant therapeutic agent; it could constitute a promising alternative treatment agent against G. lamblia infection. Full article

Giardia duodenalis is a waterborne zoonotic protozoan that causes gastrointestinal tract inflammation in humans, cattle, and other animals. The aim of the present study was to estimate the prevalence and potential risk factors for Giardia infection in cattle in Latvia. During 2020–2021, a total of 973 individual faecal samples from cattle aged from 1 day to 12 years old, from 32 cattle herds, were tested for Giardia cyst presence with immunofluorescence staining followed by Giardia assemblage differentiation targeting beta-giardin gene. Using a questionnaire, information was collected to estimate the potential risk factors for G. duodenalis infection in cattle herds. Giardia was found in 8.4% of the examined cattle with a mean intensity of 5756 cysts per gram of faeces. The highest prevalence was observed in the 0 to 3-month-old calves (16.4%). At least one Giardia shedding animal was found in 27 herds with an overall prevalence of 84.4%. Significantly higher prevalence was found for cattle infected with G. duodenalis assemblage E compared to that infected with assemblage A: 88.7% and 11.3%, respectively. Protective factors such as age and rodent control and change of shoes were found to be significant for Giardia infection, while isolating calves for diarrhoea and water bodies (ponds/lakes) in pasture were potential risk factors in Latvian cattle. Full article