Presence Of Pathogens Research Articles

The prevalence of pathogens in ticks collected from humans in Belgium, 2021, versus 2017

BackgroundTicks carry a variety of microorganisms, some of which are pathogenic to humans. The human risk of tick-borne diseases depends on, among others, the prevalence of pathogens in ticks biting humans. To follow-up on this prevalence over time, a Belgian study from 2017 was repeated in 2021.MethodsDuring the tick season 2021, citizens were invited to have ticks removed from their skin, send them and fill in a short questionnaire on an existing citizen science platform for the notification of tick bites (TekenNet). Ticks were morphologically identified to species and life stage level and screened using multiplex qPCR targeting, among others, Borrelia burgdorferi (sensu lato), Anaplasma phagocytophilum, Borrelia miyamotoi, Neoehrlichia mikurensis, Babesia spp., Rickettsia helvetica and tick-borne encephalitis virus (TBEV). The same methodology as in 2017 was used.ResultsIn 2021, the same tick species as in 2017 were identified in similar proportions; of 1094 ticks, 98.7% were Ixodes ricinus, 0.8% Ixodes hexagonus and 0.5% Dermacentor reticulatus. A total of 928 nymphs and adults could be screened for the presence of pathogens. Borrelia burgdorferi (s.l.) was detected in 9.9% (95% CI 8.2–12.0%), which is significantly lower than the prevalence of 13.9% (95% CI 12.2–15.7%) in 2017 (P = 0.004). The prevalences of A. phagocytophilum (4.7%; 95% CI 3.5–6.3%) and R. helvetica (13.3%; 95% CI 11.2–15.6%) in 2021 were significantly higher compared to 2017 (1.8%; 95% CI 1.3–2.7% and 6.8%; 95% CI 5.6–8.2% respectively) (P < 0.001 for both). For the other pathogens tested, no statistical differences compared to 2017 were found, with prevalences ranging between 1.5 and 2.9% in 2021. Rickettsia raoultii was again found in D. reticulatus ticks (n = 3/5 in 2021). Similar to 2017, no TBEV was detected in the ticks. Co-infections were found in 5.1% of ticks. When combining co-infection occurrence in 2017 and 2021, a positive correlation was observed between B. burgdorferi (s.l.) and N. mikurensis and B. burgdorferi (s.l.) and B. miyamotoi (P < 0.001 for both).ConclusionsAlthough the 2021 prevalences fell within expectations, differences were found compared to 2017. Further research to understand the explanations behind these differences is needed.Graphical

Pathogen Prevalence in Cetaceans Stranded along the Italian Coastline between 2015 and 2020.

The monitoring of stranded marine mammals represents a strategic method to assess their health, conservation status, and ecological role in the marine ecosystem. Networks worldwide track stranding events for the passive monitoring of mortality patterns, emerging and reemerging pathogens, climate change, and environmental degradation from a One Health perspective. This study summarizes pathogen prevalence data from the Italian Stranding Network (ISN) derived from post-mortem investigations on cetaceans found dead stranded along the Italian coastline between 2015 and 2020. The decomposition of the carcasses and logistics limited the post-mortem examination to 585 individuals, out of 1236 single-stranding reports. The most relevant pathogens identified were Cetacean Morbillivirus, Herpesvirus, Brucella spp., and Toxoplasma gondii, whose roles as environmental stressors are well known, despite their real impact still needing to be investigated in depth. Statistical analysis showed that age and sex seem to be positively related to the presence of pathogens. This study represents the first step in harmonizing post-mortem investigations, which is crucial for evidence-based conservation efforts. Implementing diagnostic and forensic frameworks could offer an indirect insight into the systematic monitoring of diseases to improve the identification of regional and temporal hotspots in which to target specific mitigation, management, and conservation strategies.

Causal associations between gut microbiota and premature rupture of membranes: a two-sample Mendelian randomization study.

Previous study has indicated a potential link between gut microbiota and maternal pregnancy outcomes. However, the causal relationship between gut microbiota and premature rupture of membranes (PROM) remains a topic of ongoing debate. A two-sample Mendelian Randomization (MR) study was used to investigate the relationship between gut microbiota and PROM. Genetic data on gut microbiota was obtained from the MiBioGen consortium's largest genome-wide association study (GWAS) (n=14,306). Genetic data on PROM (3011 cases and 104247 controls) were sourced from publicly available GWAS data from the Finnish National Biobank FinnGen consortium. Various methods including Inverse variance weighted (IVW), MR-Egger, simple mode, weighted median, and weighted mode were utilized to assess the causal relationship by calculating the odd ratio (OR) value and confidence interval (CI). Sensitivity analyses for quality control were performed using MR-Egger intercept tests, Cochran's Q tests, and leave-one-out analyses. The IVW method revealed that class Mollicutes (IVW, OR=0.773, 95%CI: 0.61-0.981, pval = 0.034), genus Marvinbryantia (IVW, OR=00.736, 95%CI: 0.555-0.977, pval = 0.034), genus Ruminooccaceae UCG003 (IVW, OR=0.734, 95%CI: 0.568-0.947, pval = 0.017) and phylum Tenericutes (IVW, OR=0.773, 95%CI: 0.566-1.067, pval = 0.034) were associated with a reduced risk of PROM, while genus Collinsella (IVW, OR=1.444, 95%CI: 1.028-2.026, pval = 0.034), genus Intestinibacter (IVW, OR=1.304, 95%CI: 1.047-1.623, pval = 0.018) and genus Turicibacter (IVW, OR=1.282, 95%CI: 1.02-1.611, pval = 0.033) increased the risk of PROM. Based on the other four supplementary methods, six gut microbiota may have a potential effect on PROM. Due to the presence of pleiotropy (pval=0.045), genus Lachnoclostridium should be ruled out. No evidence of horizontal pleiotropy or heterogeneity was found in other microbiota (pval >0.05). In this study, we have discovered a causal relationship between the presence of specific probiotics and pathogens in the host and the risk of PROM. The identification of specific gut microbiota associated with PROM through MR studies offers a novel approach to diagnosing and treating this condition, thereby providing a new strategy for clinically preventing PROM.

A cholera model coupling within-host and between-host with age-dependent and asymptomatic infections

In this paper, a coupling cholera epidemic model is proposed, in which the pathogens could both spread within-host and between-host, meanwhile, there exist age-dependent infection between the asymptomatic and symptomatic infected people. For the fast-time subsystem, the infection-free and endemic equilibria are both globally asymptotically stable. For the slow-time subsystem, the basic reproduction number R0 is determined, by which we observe that the disease-free equilibrium is globally asymptotically stable (the absence of pathogens in environment) if R0<1, while the endemic equilibrium is globally asymptotically stable (the presence of pathogens in environment) when R0>1. The theoretical results are illustrated by numerical simulations, by which we find that age-dependent and asymptomatic infections may further promote cholera spread. Besides, the linking of pathogen transmission at the individual level with infection at the population level could result in forward or backward bifurcation.

Is The Peri-Implantitis Involved With Brain Inflammation And May Contribute To Neurodegenerative Disorders?

Oral rehabilitation encompasses the restoration of oral function, addressing issues related to the teeth, gums, and other oral structures. Dental implants have become the gold standard for the replacement of single or multiple missing teeth, but in individuals with poor oral hygiene, the accumulation of dental plaque biofilm can trigger a local immune and inflammatory host response leading to peri-implant mucositis (a reversible condition with localized therapies) or peri-implantitis (characterized by bone loss accompanied by a persistent immune and inflammatory host response). The presence of periodontal pathogens at sites with peri-implantitis has been reported in several studies, and there is extensive documentation of similarities in microbial profiles between periodontitis sites and peri-implantitis sites. Thus, periodontitis/apical periodontitis can reach distant organs, especially the brain. This can lead to the development or exacerbation of inflammatory conditions. Similarly, the microorganisms and their products responsible for inducing peri-implantitis can potentially cause inflammatory conditions in the brain like periodontitis/apical periodontitis. Then, it is plausible to infer that peri-implantitis may be used the same way to induce and/or potentialize brain inflammation

Microbiological aspects of dental health in children with osteogenesis imperfecta

Background. Oral microbiome actively affects the child’s health and is an available tool for diagnosing and predic­ting dental and systemic diseases. Studying the colonization of the oral cavity by cariogenic and periodontopathogenic bacteria, given the congenital, genetically determined decrease in the quality of collagen in children with osteogenesis imperfecta, is an urgent problem. The purpose of the study was to determine the level of cariogenic and periodontopathogenic microorganisms in the oral cavity of children with osteogenesis imperfecta. Materials and methods. Clinical studies were conducted with the participation of children aged 2 to 17 years diagnosed with osteogenesis imperfecta, in whom the level of contamination of the oral cavity with cariogenic bacteria Streptococcus mutans and Lactobacter spp. and periodontal pathogens Porphyromonas gingivalis, Actinobacillus actinomycetemcomitans, Treponema denticola, Bacteroides forsythus, Prevotella intermedia was determined. Results. All children with osteogenesis imperfecta were found to have a borderline high level of Streptococcus mutans contamination and the presence of periodontal pathogens of the first order, mainly in the form of monocultures in preclinical concentration, which, against the background of low collagen quality, indicates a sufficiently high risk of developing ­caries and periodontal diseases.

Detection of Extended-spectrum β-lactamase-producing Klebsiella pneumoniae and Escherichia coli in wastewaters of Madurai, India

The present study aimed to determine the presence of Klebsiella pneumoniae and Escherichia coli with extended-spectrum β-lactamase (ESBL)s property from treated wastewater effluents. Treated effluent samples were collected from two major water treatment plants which located at Avaniyapuram and Sakkimangalam, Madurai, Tamil Nadu, India. Among the 51 isolates, 56.86 % represented E. coli (18 from Avaniyapuram and 11 from Sakkimangalam) and 43.14 % were K. pneumoniae (7 from Avaniyapuram and 15 from Sakkimangalam). Based on the ESBL propensity, E. coli was overrepresented in the present study. All the isolates turned positive for ESBL, while 5.88 % of K. pneumoniae and 7.84 % of E. coli were positive for carbapenemases. Further, K. pneumoniae isolates from both sites showed 100 % resistance to beta-lactams, with resistance to other antibiotics such as tetracycline and meropenem. E. coli isolates were 100 % resistant to ceftazidime and cefuroxime, and 88.9 % were resistant to amoxicillin/clavulanate and ceftriaxone. The MAR indices observed in the present study for E. coli and K. pneumoniae were above the threshold value of 0.2 suggested a high risk of environmental contamination. These findings highlighted the need for routine surveillance at appropriate intervals for the presence of ESBL producing pathogens and other MDR pathogens in the environment to provide proper clinical management, develop various counter measures and policies to address and halt the spread of such potential threats.

Screening for White Spot Syndrome Virus (WSSV) in pink shrimp (Penaeus paulensis) from Rocha Lagoon, Uruguay

Penaeus paulensis (pink shrimp) is an important resource for small-scale fisheries in the brackish coastal lagoons of Uruguay. No viral diseases have been detected in shrimp populations in the Uruguayan territory. The presence of viral pathogens, such as White Spot Syndrome Virus (WSSV) and Infectious Hypodermal Haematopoietic Necrosis Virus (IHHNV) in wild shrimp populations has been previously reported in Brazil and Argentina.We investigated the presence of WSSV in wild populations of penaeid shrimp from Rocha Lagoon, Uruguay. We sampled 70 specimens of juvenile P. paulensis and assessed the presence of these viral pathogens using nested PCR and histology. Gill tissue from the 70 samples was divided into 14 pools of 5 individuals for DNA extraction and PCR analysis. We also retested each pooled sample individually. The nested PCR procedure described in the WOAH aquatic animal manual was used. A subset of 20 individual specimens were also processed using standard histological techniques.The results showed that WSSV was not detected in the pooled or individually tested samples. We found no evidence of the presence of the viral genome or gill lesions in the samples analysed. This indicates that the fishery is still likely to be free of WSSV infection. The procedures and information generated can be used as a baseline study for future implementation of surveillance programmes in the country.

Microsporidian coinfection reduces fitness of a fungal pathogen due to rapid host mortality.

Infection outcomes can be strongly context dependent, shifting a host-symbiont relationship along a parasitism-mutualism continuum. Numerous studies show that under stressful conditions, symbionts that are typically mutualistic can become parasitic. The reverse possibility, a parasite becoming mutualistic, has received much less study. We investigated whether the parasitic microsporidium Ordospora pajunii can become beneficial for its host Daphnia dentifera in the presence of the more virulent fungal pathogen Metschnikowia bicuspidata. We found that, even though infection with O. pajunii reduces the frequency of penetration of M. bicuspidata spores into the host body cavity, it does not improve the survival or reproduction of the host; conversely, coinfection increased the mortality of Daphnia. This shorter lifespan of coinfected hosts disrupted the life cycle of M. bicuspidata, greatly reducing its fitness. Thus, coinfection with both pathogens was detrimental to the host at the individual level but might be beneficial for the host population as a result of greatly reduced production of M. bicuspidata spores. If so, this would mean that O. pajunii outbreaks should delay or prevent M. bicuspidata outbreaks. In support of this, in an analysis of dynamics of naturally occurring outbreaks in two lakes where these pathogens co-occur, we found a time lag in occurrence between O. pajunii and M. bicuspidata, with M. bicuspidata epidemics only occurring after the collapse of O. pajunii epidemics. Thus, these results suggest that the interaction between co-occurring symbionts, and the net impact of a symbiont on a host, might be qualitatively different at different scales.IMPORTANCEUnderstanding the factors that modify infection probability and virulence is crucial for identifying the drivers of infection outbreaks and modeling disease epidemic progression, and increases our ability to control diseases and reduce the harm they cause. One factor that can strongly influence infection probability and virulence is the presence of other pathogens. However, while coexposures and coinfections are incredibly common, we still have only a limited understanding of how pathogen interactions alter infection outcomes or whether their impacts are scale dependent. We used a system of one host and two pathogens to show that sequential coinfection can have a tremendous impact on the host and the infecting pathogens and that the outcome of (co-)infection can be negative or positive depending on the focal organization level.

The Impact of the Middle Ear Microbiota on Otitis Media Outcomes: A Meta-Analysis of Longitudinal Studies

Introduction: Otitis media (OM), a prevalent middle ear inflammation, often involves microbial colonization. The composition of the middle ear microbiota may influence OM outcomes, including recurrence, persistence, and treatment response. This meta-analysis investigated the relationship between the middle ear microbiota and OM outcomes. Methods: Longitudinal studies published from 2018 to 2024 that explored the middle ear microbiota and OM outcomes were systematically searched in PubMed, Embase, and Web of Science. Data on study design, participant characteristics, microbiota analysis, and OM outcomes were extracted. The risk of bias was assessed using the Newcastle-Ottawa Scale. A random-effects model was used to pool effect estimates. Results: A total of 15 studies (n = 2,540 participants) met the inclusion criteria. The middle ear microbiota diversity was significantly lower in children with recurrent OM compared to those without (standardized mean difference [SMD] = -0.45, 95% confidence interval [CI] -0.62 to -0.28, p &lt; 0.001). The presence of specific pathogens, including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis, was associated with an increased risk of OM recurrence (odds ratio [OR] 1.75, 95% CI 1.32 to 2.31, p &lt; 0.001). Additionally, microbial dysbiosis was associated with delayed resolution of OM and increased antibiotic treatment failure. Conclusion: The middle ear microbiota composition significantly impacts OM outcomes. Reduced diversity and specific pathogens are associated with increased OM recurrence. These findings highlight the potential for microbiota-targeted interventions in OM management.

Rapid Molecular Diagnostics of Pneumonia Caused by Gram-Negative Bacteria: A Clinician's Review.

With approximately half a billion events per year, lower respiratory tract infections (LRTIs) represent a major challenge for the global public health. Among LRTI cases, those caused by Gram-negative bacteria (GNB) are associated with a poorer prognostic. Standard-of-care etiologic diagnostics is lengthy and difficult to establish, with more than half of cases remaining microbiologically undocumented. Recently, syndromic molecular diagnostic panels became available, enabling simultaneous detection of tens of pathogen-related and antimicrobial-resistance genetic markers within a few hours. In this narrative review, we summarize the available data on the performance of molecular diagnostics in GNB pneumonia, highlighting the main strengths and limitations of these assays, as well as the main factors influencing their clinical utility. We searched MEDLINE and Web of Science databases for relevant English-language articles. Molecular assays have higher analytical sensitivity than cultural methods, and show good agreement with standard-of-care diagnostics regarding detection of respiratory pathogens, including GNB, and identification of frequent patterns of resistance to antibiotics. Clinical trials reported encouraging results on the usefulness of molecular assays in antibiotic stewardship. By providing early information on the presence of pathogens and their probable resistance phenotypes, these assays assist in the choice of targeted therapy, in shortening the time from sample collection to appropriate antimicrobial treatment, and in reducing unnecessary antibiotic use.

Microbiological and decomposition analysis of mass mink burial sites during the COVID-19 pandemic

In 2020, Denmark buried approximately four million culled, farmed mink in mass graves treated with slaked lime due to widespread SARS-CoV-2 infections. After six months, environmental concerns prompted the exhumation of these cadavers. Our analysis encompassed visual inspections, soil pH measurements, and gas emission assessments of the grave environment. Additionally, we evaluated carcasses for decay status, cadaverine content, and the presence of various pathogens, including SARS-CoV-2 and mink coronavirus. Our findings revealed minimal microbial activity and limited carcass decomposition. Although viral RNA from SARS-CoV-2 and mink coronavirus, along with DNA from Aleutian mink disease virus, were detected, the absence of infectious SARS-CoV-2 in cell culture assays suggests slow natural degradation processes. This study provides critical insights for future considerations in managing mass burial scenarios during outbreaks of livestock-associated zoonotic pathogens.

Myddosomes in Toll-like receptor signaling-one to bind and rule them all.

Toll-like receptors (TLRs) are innate immune sensors for the presence of pathogens and endogenous danger signals. TLR activation results in conserved intracellular signaling events that orchestrate inflammation and antimicrobial defense. While the identity and interplay of key TLR signaling components are well established, how these largely cytosolic proteins are physically connected is not well understood. For the activation of conserved intracellular signaling events, most TLRs engage the adapter MyD88 (myeloid differentiation primary response 88), which assembles into higher-order protein complexes, myddosomes. In their recent publication, Fisch etal. present evidence that oligomeric myddosomes detach from initiating TLRs and evolve into larger scaffolds that dynamically assemble not only proximal but also distal cytosolic elements required to execute the entire cascade of the TLR-MyD88 signaling pathway. Coinciding with decline in TLR signaling over time, myddosomes progressively recruit autophagy machinery that mediates myddosome clearance. These findings expand the current understanding of TLR signaling by positioning myddosomes as the central structural element that physically assembles the key executors and regulators of TLR-MyD88-dependent intracellular signaling cascades.

Understanding the dissemination of viruses and viroids identified through virome analysis of major grapevine rootstocks and RPA-based detection of prevalent grapevine virus B

Grapevine stocks are generally vegetatively propagated for the commercial cultivation. The propagation is predominantly done on rootstocks with >90 % of plant stocks propagated on Dogridge rootstock alone in India. Three additional rootstocks i.e. Paulsen, SO4 and Ramsey are also used for grapevine propagation on a limited scale. However, no information is available on the health status of these rootstocks being used by nurserymen and growers. Therefore, these rootstocks were collected from nurseries of five different locations and subjected to high-throughput sequencing (HTS) to determine the spectrum of viruses and viroids. The de novo assembly of unaligned reads revealed the presence of genome sequences of nine viruses viz. grapevine rupestris stem pitting-associated virus (GRSPaV), grapevine leafroll-associated virus 3 (GLRaV-3), grapevine leafroll-associated virus 4 (GLRaV-4), grapevine virus A (GVA), grapevine virus B (GVB), grapevine virus D (GVD), grapevine virus F (GVF), grapevine virus L (GVL), grapevine fleck virus (GFkV) and five viroids viz. hopstunt viroid (HSVd), grapevine yellow speckle viroid 1 and 2 (GYSVd-1 and GYSVd-2), Australian grapevine viroid (AGVd) and grapevine latent viroid (GLVd). The identified viruses and viroids were further confirmed through RT-PCR and Sanger sequencing. Indexing for the presence of these graft-transmissible pathogens in 43 rootstocks and 23 scion samples collected through field surveys indicated that infected rootstocks are the probable source for dissemination of these viruses and viroids in grapevine scions. As GVB was the most prevalent virus in all the rootstocks and scions as observed in RT-PCR testing, a simplified crude sap-based recombinase polymerase amplification (RPA) assay was optimized for its rapid detection. The present study highlights that grapevine rootstocks are reservoir of viruses and viroids and source for their dissemination in grapevine vineyards. Findings of the study including the optimized simplified cost-effective isothermal nucleic acid-based detection technique for GVB will be highly useful for production of certified clean rootstocks of grapevine in India.

Molecular detection of some zoonotic tick-borne pathogens in ticks collected from camels (Camelus dromedarius) as hosts and wild rodents as potential reservoirs.

Ticks and tick-borne pathogens pose a great threat to human and animal health. The present study aimed to determine the prevalence of ticks that infest camels and investigate the presence of tick-borne pathogens in the blood of camels, associated ticks, and surrounding rodents as reservoirs. From 100 inspected camels, from different localities in the Giza governorate, 1000 ixodid ticks were collected; these ticks belonged to three genera: Hyalomma, Amblyomma, and Rhipicephalus. The genus Hyalomma was represented by four species, Hyalomma dromedarii was the most prevalent species (55.4%), followed by Hyalomma excavatum (22%), Hyalomma impeltatum (11.6%) and Hyalomma rufipes (2.8%). The genus Amblyomma was represented by two species, Amblyomma gemma (2.8%) and Amblyomma marmoreum (2.7%), while the genus Rhipicephalus was represented by only one species, Rhipicephalus pulchellus (2.7%). Ticks, camel blood, and rodents (total number 100 brown rats) are screened for tick-borne pathogens (Borrelia burgdorferi, Borrelia miyamotoi, Babesia sp., and Coxiella burnetii) using PCR. Camel blood was found to be infected with Borrelia burgdorferi (66.6%), Borrelia miyamotoi (55%), and Babesia sp. (11.6%). Coxiella burnetii DNA was detected in all the collected ticks but was not detected in the blood of camels or rodents. Borrelia miyamotoi was detected in 12.5% of H. impeltatum, 55% of Camels, and 6% of the rodents, which may indicate a proposed risk of dispersal of B. miyamotoi, the agent of tick-borne relapsing fever.

Energy reserves and gut microbiota of marine mussels under combined exposure to pathogens and predation risk

In recent years, environmental issues such as eutrophication have led to proliferation of pathogenic bacteria and deterioration of aquaculture environmental water quality. However, the impact of pathogenic bacteria on the mussel-predator food chain in the marine environment is not yet fully understood. In this experiment, mussels were cultured with crabs (Charybdis japonica) for 14 days. Then crabs were retained or removed and pathogenic bacteria (Vibrio alginolyticus) was added and mussels were cultured for 3 days. C. japonica and V. alginolyticus were used as two stressors to explore their effects on energy content and gut microbiota of Mytilus coruscus. The metabolic parameters (protein, carbohydrate and lipid contents) of the gills and digestive glands, and the gut microbiota of the mussels were measured. The study found that presence of predation risk significantly increased the content of protein but decreased carbohydrate and lipid contents in the gills at 14th day. After 17 days of exposure, the presence of predation risk significantly reduced protein content but significantly increased lipid content in gills of mussel. The protein content in digestive gland was significantly increased, but the lipid content was significantly decreased. The presence of predation risk and pathogens had interactive effect on the protein content in the digestive glands of mussels. The presence of V. alginolyticus and predation risk affected the community structure, species richness, and diversity of gut microbiota. The most abundant phyla noted were Bacteroidota, Proteobacteria, and Firmicutes, and the most abundant genus noted were Prevotella, Klebsiella and Dialister. Alpha diversity analysis and beta diversity analysis revealed that the presence of V. alginolyticus and predation risk altered the microbial community structure. V. alginolyticus plays a positive role in the harmful microbiota of gut microbiota. The proportion of Bacteroidota and Proteobacteria in intestinal bacteria increased significantly. Linear discriminant analysis effect size (LEfSe) showed that the biomarkers in each group are significantly different at the genus level. Significant correlations between metabolic parameters (protein content and carbohydrate content) and the level of KEGG function prediction (amino acid metabolism and carbohydrate metabolism) were observed in gills and digestive glands. This study highlights the priority of energy responses in mussels under dual predator-pathogen pressure, and also highlights the complexity of predator-pathogen interactions. A better understanding of their impact on the gut microbiota and health of marine mussels will help support the sustainability of mussel aquaculture production.

Molecular characterisation of Mycoplasma bovis isolates from consecutive episodes of respiratory disease on Dutch veal farms

Mycoplasma bovis infections are wide spread in veal calf farms and a major contributor to respiratory disease. M. bovis are genetically diverse. It is unclear how this diversity influences the virulence and epidemiology of infections on veal calf farms over time. Therefore, the aim of this study was to follow the genetic composition of M. bovis isolates on veal farms over time in a fattening round and combine this with presence of disease and presence of other respiratory pathogens. For this, M. bovis isolates were obtained from healthy and diseased calves from ten different farms at different episodes of respiratory disease in the same groups in one fattening round. A new episode of respiratory disease was defined by the practitioner based on clinical diagnosis at least 7 days after end of a previous metaphylactic treatment. These isolates were sequenced using Illumina sequencing and analysed. This resulted in 148 sequenced isolates. The isolates belonged to 9 different clusters and to the known MLST sequence types ST4 (n=9), ST6 (n=2), ST7 (n=1), ST8 (n=1), ST21 (n=32), ST29 (n=30), ST32 (n=1), ST100 (n=36), ST122 (n=17) and ST135 (n=4), and new sequence types ST222 (n=8), ST223 (n=1), ST224 (n=5) and ST225 (n=1). Major sequence types are linked to types, found in other European countries. All farms showed presence of two or more different clusters, however with different distribution patterns. Farms did not show a major shift in type distribution over time. There was a relationship between M. bovis type and region of origin of the calves and the types differed with regards of presence of variable membrane surface lipoprotein (Vsp) genes. Types were not related to disease status of the calves or presence of other major respiratory pathogens. This study underlines the complexity of M. bovis infection on veal calf farms with persistent presence of different types together in both healthy and diseased calves with or without other respiratory pathogens. Prevention of introduction of M. bovis and biosecurity measures combined with optimisation of calf resilience should have priority.

Airborne bacterial and fungal species in workstations of salmon processing plants

Significant quantities of salmon are processed daily in the industry's indoor facilities. Occupational exposure contributes to an individual's exposome. The aim of this study is to obtain knowledge about potential exposure to viable airborne species of bacteria and fungi as related to workstations in the salmon processing industry. The study was conducted in nine salmon plants along the Norwegian coast over one or two days with a one-year interval. The MAS100 was used for sampling and MALDI-TOF MS for species identification. The geometric mean concentrations of bacteria and fungi were 200 CFU/m3 and 50 CFU/m3, respectively, with the highest concentrations of bacteria found in slaughtering areas and fungi in trimming of fillets. In total 125 gram-negative and 90 gram-positive bacterial and 32 different fungal species were identified. Some genera were represented by several species e.g. Chryseobacterium (15 species), Flavobacterium (13 species), Microbacterium (12 species), Pseudomonas (37 species), and Psychrobacter (13 species). Risk class 2 (RC2, human pathogens) were found in all types of workstations and plants. Seventeen bacterial species belong to RC2, some were fish pathogens, food spoilage bacteria, or species causing foodborne disease. Among fungi, Aspergillus nidulans was frequently detected across different workstations and plants. In conclusion, bacterial and fungal concentrations were low. Fish and sea-related bacteria were found along the salmon processing line. Bacterial concentrations and species compositions differ between workstations. No particular bacterial or fungal species constituted a large fraction of all airborne species. Based on the presence of human pathogens, using protective gloves is important for the workers. The presence of human and fish pathogens and food spoilage bacteria reveals air as a transmission route for bacteria, potentially affecting workers, consumers, fish, and hygiene of processing equipment. To limit the spread of these bacteria an interdisciplinary cooperation with a One Health perspective may be relevant.

Neighbors sharing pathogens: the intricate relationship between Apis mellifera and ants (Hymenoptera: Formicidae) nesting in hives.

Ants are ubiquitous and eusocial insects that exhibit frequent physical contact among colony members, thereby increasing their susceptibility to diseases. Some species are often found in beehives and in their surroundings, where they exploit the food resources of honey bees. This intricate relationship may facilitate the interspecific transmission of honey bee pathogens to ants, although ants themselves may contribute to spillback phenomena. The objective of this study was to assess the presence and abundance of honey bee pathogens in ants sampled from Italian apiaries. A total of 37 colonies within 24 apiaries across 7 regions were monitored. In total, 6 pathogens were detected in adult ants and 3 in the brood. In particular, the study revealed a high prevalence of honey bee pathogens in ants, with DWV, BQCV, and CBPV being the most commonly encountered. The brood also tested positive for the same viruses. Notably, all analyzed viruses were found to be replicative in both adult ants and ant broods. Furthermore, co-infections were prevalent, suggesting complex pathogen interactions within ant populations. Statistical analysis indicated significant differences in pathogen prevalence and abundance among ant species and sample types. The findings highlight active infection in both the ants and the brood, suggesting a potential role of ants as reservoir hosts and vectors of honey bee pathogens emphasizing the need for further research to understand the implications of interspecific pathogen transmission on ant and bee health.

A rapid LAMP assay for the diagnosis of oak wilt with the naked eye

BackgroundOak wilt disease, caused by Bretziella fagacearum is a significant threat to oak (Quercus spp.) tree health in the United States and Eastern Canada. The disease may cause dramatic damage to natural and urban ecosystems without management. Early and accurate diagnosis followed by timely treatment increases the level of disease control success.ResultsA rapid assay based on loop mediated isothermal amplification (LAMP) was first developed with fluorescence detection of B. fagacearum after 30-minute reaction time. Six different primers were designed to specifically bind and amplify the pathogen’s DNA. To simplify the use of this assay in the field, gold nanoparticles (AuNPs) were designed to bind to the DNA amplicon obtained from the LAMP reaction. Upon inducing precipitation, the AuNP-amplicons settle as a red pellet visible to the naked eye, indicative of pathogen presence. Both infected and healthy red oak samples were tested using this visualization method. The assay was found to have high diagnostic sensitivity and specificity for the B. fagacearum isolate studied. Moreover, the developed assay was able to detect the pathogen in crude DNA extracts of diseased oak wood samples, which further reduced the time required to process samples.ConclusionsIn summary, the LAMP assay coupled with oligonucleotide-conjugated gold nanoparticle visualization is a promising method for accurate and rapid molecular-based diagnosis of B. fagacearum in field settings. The new method can be adapted to other forest and plant diseases by simply designing new primers.